Nghiên cứu chế tạo vật liệu nano và màng mỏng

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Nghiên cứu chế tạo vật liệu nano và màng mỏng

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ĐẠI HỌC QUỐC GIA HÀ NỘI TRƯỜNG ĐẠI HỌC KHOA HỌC T ự NHIÊN Tên đê tài: NGHIÊN CỨU CHÊ TẠO VẬT LIỆU NANO VÀ MÀNG MỎNG MÃ SỐ: Q T - - Chủ đề tài: Khúc Quang Đạt Cán tham gia: Phùng Quốc Bảo Dư Văn Hiệp Phạm Trung Hoàng Đ A I H O C Q U Ố C G IA H À N Ô I TRUNG TÂM ĨH Ỏ N G TIN THƯ VIÊN DT/ Hà N ội-2 0 BÁO CÁO TÓM TẤT a Tên đề tài: nghiên cứu chế tạo vật liệu nano màng mỏng Mã sô: QT - 05 - 21 b Chủ đề tài: Khúc Quang Đạt c Cán tham gia: Phùng Quốc Bảo Dư Văn Hiệp Phạm Trung Hoàng d Mục tiêu nội dung nghiên cứu - Mục tiêu: Nghiên cún chế tạo đặc trưng hệ xúc tác LaxSi*ị.xFevCo1.>,03±5 /MCM-41và hoạt tính xử lý c o HC khí thải động Nghiên cứu tổng hợp CuS dạng cầu rỗng, màng mỏng ZnO ZnS - Nội dung: Nghiên cứu quy trình chế tạo nano xốp lỗ trung bình MCM-41 đặc trưng xốp bề mặt chúng Nghiên cứu quy trinh chế tạo LaxSiYxFe^COi.yOais /MCM-41 ĩ^ghiên cứu đặc trưng xử lý c o HC khí thải động hệ xúc tác LaxSiYxPeyCoỊ.yOsts./MCM-ềl Nghiên cún tổng hợp đậc trưng CuS dạng cầu rỗng Nghiên cún tổng họp màng mỏng vi tinh thể ZnO phương pháp sol-gel Tổng họp màng mỏng ZnS bàng phương pháp CBD số đặc trung chúng e Các kết đạt Đã tìm quy trình chế tạo nano xốp lỗ trung bình MCM-41 đặc trưng xốp bề mặt cửa chúng : kích thước cấu trúc lỗ, diện tích bề mặt, Đã tìm quy trình chế tạo màng perovskit bề mặt lỗ xốp MCM'41 phương pháp tẩm, đặc trưng xốp bề mạt chúng : kích thước cấu trúc lỗ, diện tích bề mặt, đặc trưng hấp phụ hố học CO Đã tìm đặc trưng xử lý c o HC khí thải động xúc tác LajjSrj.jjFeyCo^yOa+s vai trò ảnh hưởng Fe Co Đã tìm quy trình tổng hợp đặc trưng CuS dang cầu rỗng lừ đồng nitrat thioure phương pháp thuỷ nhiệt Đã tim quy trình tổng hợp màng mỏng vi tinh thể ZnO phương pháp sol-gel tìm hiểu số đặc trưng chúng : XRD, SEM huỳnh quang Đã tìm quy trình tổng hợp màng mỏng ZnS phuơne pháp CBD số đặc trưng chúng: XRD, SEM Raman f.Tinh hình sử dụng kinh phí: Tổng kinh phí dược cấp thực để tài 10 triệu đồng du hỗ trơ phần mua hóa chất dụng cụ, phân tích kết quả, th mướn nhân cơng., KHOA QUẢN LÝ CHỦ NHIÊM ĐỀ TÀ[ PGS TS Trần Thi N h M Khúc Q uang Đạt C QUAN CHỦ TRÌ ĐỂ TÀI PSS.TS SUMARY R E PO R T OF THE SCIENTIFIC RESEARCH SUBJECT Title of subject: Study on preparation of nano - metarials and thin films CODE: QT- 05-21 Head of subject: KHÚC QUANG ĐẠT p articipants : PHÙNG QUỐC BẢO D VĂN HIỆP PHẠM TRUNG HOÀNG Purpose and content of research: a Purpose: - Study on preparation, characteristics of catalysts LaxSiYxFeyCoi.jOsiS /MCM-41 and treatment of CO, HC in auto exhaut - Study on preparation of CuS h ollow spheres, ZnO thin film s and ZnS thin film s b Content: - Study on preparation of nanoporous MCM-41 and it’s characteristics - Study on preparation of catalysts L axS r^P eyC o^O atõ/M C M -ẩl - Study on treatment of CO, HC in auto exhaut - Study on preparation and characteristics of C uS h o llo w spheres - Study on preparation of microcrystaline ZnO thin film by sol-gel method - Study on preparation of ZnS thin films by CBD method The obtained results The main results obtained from the research are listed below: ( - Nano porous MCM-41 was prepared and characterised : structure and size of pore, BET, - Catalysts LaxSrj.xFeyCOj.yOste /MCM-41 w as prepared and characterised structure and size of pore, BET, chem ical adsorbtion of CO, FT-IR, XRD, The im pact of Fe and Co content in perovskites LajjSrj.xFeyCoj.yChiB on the treatment of CO, HC in exhaut CuS h o llo w spheres w as prepared by hydrothermal m ethod and characterised Microcrystaline ZnO thin film was prepared by sol-gel method and characterised by XRD SEM, photoluminescence, techniques ZnS thin films was prepared by CBD method and characterised by XRD, SEM, Raman, techniques, RESPONSIBLE PERSON Khúc Quang Đạt ĐẠI HỌC QUỐC GIA HÀ NỘI TRƯỜNG ĐẠI HỌC KHTN CỘNG HOÀ XÃ HỘI CHỦ NGHĨA VIỆT NAM Đ ộc lập - Tư - Hạnh phúc :K***** # ĩ'fl 5j« :Ịs 5js ĩ|s 5Ì< ĩfí M ã só\.{ấ.ỉ> ũẪ,-.ẰÌ H N ô i, ngày 'ị Ị th n iị Ị ũ năm 200 HỢP ĐỔNG NGHIÊN c ứ u KHOA HOC THỰC HIỆN ĐỂ TÀI CẤP ĐAI HOC QUỐC GIA NĂM 2005 - Cãn vào kẽ hoạch giao nhiệm vụ KH- CN nãin 2005 cua Đại học Quốc í ia Hà Nôi cho Trường Đai học K h o a hoc Tự nhiên - Căn Qu y định tạm thời sô / Q Đ - K H K T niỉàv 27 thane năm 1989 cua Chu nhiêm u ý ban Khoa học Kỹ thuật Nh nước (nay Bộ Khoa học C n ” níỉhệ) vẽ việc ký kết Hợp dồng khoa hoc kỹ thuật CH ÚNG TỒI GỒM I ■Bẽn lĩiau (A ) là: Trường Đai hoc K hoa hoc Tư nhiẽn - Tài khoan: 301.01.036.1 K h o bạc Nhà nước Đóng Đa - Đai diện là: CỈS.TS Trần INghi Chức vụ: Phó Hiệu trướng Trường Đai hoc Khoa hục Tư nhiên, Đ H Q ÍỈH N - Địa chi: 334 Nguye n Trãi, Thanh Xuân, Hà Nội - Đ i ệ n thoại: 584287 Bẽn nhan (B) là: * Tạp khoa hoc thực liién đè tài mã so & L L 1 - Đai diên Òns/Bà: f s l u Í C K(.(/>L ị d í - Chức vụ: C/? (U.\Ệ Ầ'.Ll.ĩ? - Địa chí: ÍÌL.ÂĨ? ỉ ũ ữ j a u * Khua quàn l ý : ; - Đại diện Ỏ n g / B : U ữ ịỉ ĩ.ỈL f À Ỉằ /ịf& - Chức vụ: F h p đ w : n Ẩ m n r f í ì M Hai bủn thoa thuận kí két hợp dons’ N C K H với nhữna dicu khoán sau ( i a \ : vết thực thực đé tài tài Điêu I : Bên B cam kết N í Ị Ỉ UC.Ỏ n í ỏ ũũh x.L h i L ỉí.ự ỉ ĩ i ĩ ^ O m iỳ n x T Ệ - Nội dung nghiên cứu, tiến độ, kết đề tài năm 2005 ghi phụ lụcl ; Điều 2: Kinh phí hỗ trợ đề tài năm 2005 : đồng (Ghi chữ: ^n.\.ULí:.I ÁT* ^ ' ~ ) Điêu 3: Bẽn B có trách nhiệm: ũ - Sử dụng kinh phí cấp theo chế độ tài Nhà nước - Thực nội dung tiến độ đề tài - Lập hồ sơ theo dõi tiến độ thực đề tài, báo cáo định kỳ quyếttốn tài theo chế độ hành Đieu 4; Sau hoàn thành hợp đồng hai bên tổ chức đánh giá nghiệm thu sản phẩm đê tài theo quy định hành Điểu 5: Hợp đồng có hiệu lực từ ngày ký Hợp đồng lập thành 05 có giá trị nhau, lưu Phòng Khoa học - Cơng nghệ (01 bản), Phòng kế hoạch-Tài vụ (02 bản) Khoa quản lý (01 bản) Chủ nhiệm đề tài (01 bản) ĐẠI DIỆN BÊN B KHOA QUẢN LÝ CHỦ NHIẸiM ĐÈ TÀI PHÓ HIỆU T RƯỚNG TRƯỜ NG ĐẠI HỌC KHOA HỌC TỤ NHIÊN PHỤ LỤC HỢP ĐỒ NG NĂM 2005 Phụ lục (Hợp đồng năm 2005) Mã số đề Chủ nhiệm đề tài: Ãvír: NỘI DUNG, TIẾN Đ ộ VÀ SẢN PHẨM c ụ THỂ CỦA ĐÈ TÀI STT N ội d ung nghiẽn cứu r l tv o.u u V v-íK '^ í - £ t;T_> < C'( l i c^l a T h i gian th ụ c t đến 12/200 ƯJÍ, y ^ ù r)ùv H anoi U niv e rsity o f Sciences, V ietn am N a tion a l U niversity, Hanoi n g u y e n rai R o a d , T h a n h X u a n Distr., Hanoi, V ie tn a m ; Email: b a o p q @ v n u e d u D e p a r t m e n t o f C h e m is tr y , H anoi Univ ersity o f Sciences, V ie tn a m N a tio na l U niv e rsity ” Hanoi abstr ac t Zinc suffide thin film s a re g r o w n from chem ical bath d e p o sitio n at the te m p e a r t u r e b e lo w 0 ° c without any p o st- a n n e a lin g p ro c ess es All film s that were investigated a re p o ly c r y s ta llin e with a wurzite (hexagonal) structure S c a n n in g E le c tr o n M ic ro sc o p y (SE M ) stud y s h o w s that the h o m o g e n e i ty and the c om p actness o f the Z n S film s a re d e p e n d e n t on the molar ratio o f zin c a ce ta te to thiourea, the d e position time and the b a th t e m p e a rtu re T h e films are also characterized by M i c r o - R a m a n spectra K e y w o r d s : C h e m ic a l b a th d e p o s itio n ; Z n S thin films Solar cells IN T R O D U C T IO N Zinc sulfide is o n e o f the z in c - b a s e d b in ary II—VI c o m p oun ds w h ic h a re o f g re at optoelectronic a p p li c a t io n [1,2] material is a w id e g a p and i m p o rta n c e in the B e c a u s e o f this d irec t transition glass plate 20x20x1 m m in size A fter c leaning the substrate with a neutral c le an in g agent in an ultrasonic bath, it was c lc an e d a gain with distilled w ater and a ceto ne su c c ess iv ely in that bath, and then dried with hot air, and p re serv e d in a desiccator W e p r e p are d first two 1M solutions o f zinc a cetate d ih y d te and th iou re a in 50 ml o f methanol se parately A m agn e tic stirrin g-assiste d d rop ping gra dually ml o f a m m o n i a into the zinc acetate dehyd rate solution was p e rfo rm e d to ge t a clear and h o m o g e n e o u s so lutio n with pH 10 Clean glass substrates w ere then vertically inserted by suspension into the reaction bath on gradual add ition o f the thio urea solution T h e bath w as slightly stirred at a tem pe ture o f - " c T o aim at op tim izin g the growth param eters, several reaction bath co m p o s itio n s (the m olar ratio o f zinc a cetate to thio urea was kepi at : and I :l 25) were used for v a riou s de p o sitio n times T h e Z nS thin films w ere form ed onto the substrate with the follow ing re ac tion m e c h a n ism [t ]: Zn ( C H j C O O ) , — Z r r ' + C H , C O O ‘ sem ic onductor, it c o u ld be e ith e r an e x ce lle n t w ind ow N H + H-,0 — N H / + OH- layer in thin film s o la r c ells o r an a n tirefle ctio n coating for h e te ro ju n c tio n s o la r cells It is a poten tially Zn2' + N H « Z n ( N I I 1)45' important m aterial to b e u se d in d e v ic e s fo r the detection, e m is s io n a n d m o d u la t io n o f visible and near ultra violet light [3] In pa rticula r, Z n S is b e lie v e d to be one p r o m is in g m aterial f o r b lue light e m ittin g laser diodes [4] and th in films e le c t r o l u m i n e s c e n t displays [5] A m o n g the c h e m ic a l d e p o s i ti o n m e t h o d s , chem ical bath de p o sitio n ( C B D ) is k n o w n to p r o d u c e so la r cell grade film s o v e r a large a r e a at a low cost and low tem perature [ - ], In this w o rk , Z n S thin film s have been g ro w n by c h e m ic a l b a th d e p o s i ti o n p ro c e s s and studied as an a n tirefle ctio n c o a t i n g w h ic h is an essential part o f the so la r cell SC ( N H : ); + OH- -> S H ' + C H , N ; + H ; SH + OH' 4- * s:- + H:0 A nd the general reaction e quation can be cast into : Z n t N H j l j 2* + S C ( N H : ), + H ' Z n S i + N H + C H : N ; + 211:0 On w ith d w in g the su bstra tes a fte r the desired de p osition times, rinsiim th o ro u g h ly in distilled water a nd d ry in g in air, y e llow ish a nd a d h ere n t films were r eady for m easurem ents X-ra y diffraction a nalyse s o f the sa m p es were E X P E R IM E N T S p e rfo rm e d by u sing re fle ction s from the C u K a emission line (0 5 I n m ) into a S I E M E N S D5005 reagent g r a d e from c o m m e r c i a l m a r k e t w ithou t further d iffractom eter T h e a n g u la r step was 0.03 ° within the studied ° to ’ range, and the q ua n ta acquisition purification T h e fo llo w in g p r e c u r s o r m a te ria ls have tim e was Alt c h e m ic a ls used in this w o r k w e re analytical se cond S c a n n in g Klectron M ic ro sc op y been used for the bath s o lu tio n p r e p a tio n : ( S E M ) im ages w ere tak e n with a J C O L J S M - I L V * Zinc a ce ta te d i h y d r a t e Z n ( C H C 0 ) Ị H ; ; sc a n n in g m ic r o s c o p e * T h io u r e a ( N H )C S; * A m o n ia N H 4O H a s c o m p l e x i n g ag en t; range o f sam ples o f Z nS thin films with different de p o sitio n tim e were, o b ta in e d in U V -V IS -N 1R region * M e th ano l C H O H as so lva nt A s a su b s tr a te m a te ria l, w e u s e d a w e ll-po lishe d (up to 1000 n m ) u sing a S H I M A D Z U T h e optical ab so rp tio n uv for a 1650PC Proceedings o f the r IW O F M - r d IWONN Conference, Halong Vietnam December 6-9, 2006 (JV-VIS d o u b le b e a m s p e c t r o p h o t o m e t e r with uncoated glass slide as the re fe r e n c e E x c ite d b y the nm He-Ne laser r a d ia tio n , R a m a n s p e c tr a a re m ea su re d by n e a r infrared regions T h e y are th erefore suitable for antireflection co atin g applicatio ns a M icro-Ram an L A B R A M - I B w ith diffraction gratings of ] 80 g r o o v e s /m m a n d s c a n n in g tim e o f s R E SU L T S A N D D ISC U SSIO N While the X R D p a tte rn s o f the Z n S thin films deposited in the b a th with Z n /S = 1:1 are all featureless the typical X R D p a tte rn o f Z n S th in films deposited in (he bath with Z n /S = : 1.25 is d is p la y e d in Fig Fig T yp ica l X R D p a tte r n o f Z n S th in film s d e p o site d from the re a c tio n b a th s o lu tio n w ith Z n /S = 1:1.25 f o r the dip tim e o f h The X R D p e a k s are n ot w e lld e fine d but quite broad, indicating a h igh ly d i s o r d e r e d material with small particle size m o r p h o lo g y T h e X R D peaks at 28.258, 47.98, and c o r re s p o n d lo reflections from ( 0 ), ( 1 ), a n d ( ) p lan e s o f wurtzite hexagonal Z n S p h a se , r e spec tive ly For the as-grown and unannealed Z n S structures, the lack o f diffraction from any c u bic p lan e s in dic a te s a pre d om inan tly hexagonal structure Fig sh o w s the S E M p h o t o g p h s o f the surface of ZnS thin film s d e p o s i te d from the reaction bath solution with Z n /S = 1:1.25 for v a rio u s dip times For the deposition tim e o f h, the film surface is still not completely c o v e r e d , tile Z n S crystallites are not uniformely p r e c ip ita te d o n to the substrate, the obtained film is too thin T h a t is w hy its X R D pattern, sim ilar to F ig S E M p h o to g r a p h s o f Z n S thin f il m s d e p o site d fr o m the sa m e re a c tio n bath so lu tio n (Z n /S = ! : i.? ) f o r various dip tim es : (a) h : (b) j h a n d (Cl h the case o f Z nS films d e p o s i te d from the reaction bath solution with Z n /S = 1:1, is featureless W ith increasing the deposition tim e , th e film s g e t thic k e r and more compact The cross-sectional study o f SEM m o r p h o lo g i e s photographs of these of Z nS iL the ^ " films indicates (hat the film th ic k n e s s a re a bo ut 750 nm, 1290 nm and 1935 nm for the d e p o s itio n tim e o f h, h and QOO - h, respectiv ely H o w e v e r , the film surface b e co m es porous, less ac'^ere nt for the d e p o s i ti o n tim e o f h This might be e x p la i n e d b v the g d u a l d e cre as e o f the ZnS pre cipitation rate d u e to the lack o f p r e c u rso r ions The typical a b s o r b a n c e sp e c tr u m o f the Z n S thin films d e p o site d in h spectra th at as-grow n th e u ltr a v io le t reveal absorbance in are show n film s regio n, in F ie u re T hese have high but high transmittance n g in g fro m ~ - % in the visible and 766 T 0 OQ J -^OO o o © oo o o 800 oo iO O O oo F ig A b s o r b a n c e c h a c te ristic s o f Z n S th in film s d e p o s ite d fr o m the re a c tio n b ath so lu tio n w ith Zn s= Proceedings o f the 1” IW O F M - 3rd JWONN Conference, Haiong, Vietnam December 6-9, 2006 1:1.25 fo r the dip tim e o f h T h e c alcu la tio n s s h o w that g r o w n the Z nS films have Eg in th e nge - 3.6-3.7 e V w ith the o p tim u m as ~ 3.65 eV T h is is in very g o o d a g re e m e n t with the values o f 6-3.6 e V r e p o rte d in [9] T h e abso rption edge is ob se rv ed in the n e ig h b o u r h o o d o f nm Detailed study sh o w s that th e ab so rp tio n edge shifts tow ards lo nger w a v e l e n g th s and therefore the bandgap decreases with in cre as in g the de p o sitio n time T his trend is r e a so n a b le a g r e e m e n t w ith the results obtained in [10] T h e r e a s o n m ig h t be that in these films there w ere m o re a v a ila b le sta te s for the photons to be abso rbed T h e fact that there are no small absorption p eaks b e lo w the a b s o r p t io n e d g e might be indicative o f few structural d e f e c ts in the films optical (T O) m o d e s with Ej sym m etry at ~ 410 c m ' and with A | sy m m etry at ~ 340 c m '1, longitudinal optical (L O ) m o d e at - 690 cm ' and second order vibrations at ~ 2 c m ' 1, - 260 c m '1, - 0 c m '1 The Z nS thin film s deposited from the reaction bath solution with Z n/S = 1:1.25 for va rious dip times have been chosen for R a m a n measurements The results are presented in Fig O ne can see that all Raman spectra have the sa m e spectroscopic structure, only the bands intensities get stronger with increasing the deposition time T his indicates the precipitation o f ZnS will be pre ponderant in the reaction bath solution with Zn/S molar ratio less than unity In turn, this ensures the purity o f the film material C O N C L U SIO N ZnS thin films have been prepared by the C B D method without any heat annealing The films have been characterized usinq such structural and optical measurements as X R D patterns, SEM images, EDS, Absorbance and M ic ro -R am an spectra T h e variations o f growth param eters as starting m aterials ratio, deposition time have been studied The characterization reveals that the films have a bandgap range o f - 3.6-3.7 eV and thickness range o f - 0-20 00 A Films prepared under certain deposition c onditions are found suitable for antireflection coating applicatio ns The study on annealed as-d epo site d ZnS is in progress and will soon be published Fig R a m a n sp c c tr u m o j Cl Z n S th in f il m d e p o site d fr o m the re a c tio n b a th s o lu tio n w ith Z ii/S = I : ! 25 f o r the dip tim e o f h R e fere n ce s [!] S Ignatowicz, A K obe n dza , S e m ic o n d u c to r Thin F ilm s o f a " B u C o m p o u n d s, John W iley & Sons, N e w York, 1990 [2] H Mar, in: H.E R uda (Ed.), W idegap J l- V I C om pounds f o r O p to e le ctro n ic A p p lic a tio n s, C hapm an & Hall, N ew York, 1992, Chap [3] K c Sharma, J c G a re, J Phys D: Appl Phvs 23 (1990)1411 [4] G.K Padam, G L M a lh otra , J Appl Phys 63 (1988) 770 [5] P Pramanik, s B iswas, J Elc ctrochetn Soc 135 (1986) 350 [6 ] N d ukw e, Solar E nerg y M aterials and Solar Cells 40 (1996)123-131 [7] T Y a m ae u ch i, Y Y a m am o to , T T an a k a, Y Demizu, A Y oshida, T h in Solid Films - (1996) 375 Fig R a m a n s p e c tr a o f Z n S th in f il m s d e p o site d fr o m [ ] 1.0 Oladeji, L C h o w , T hin Solid Films 474 (2005) the reaction bath solution W i t h Zn/S - 77-83 11- Jor [9] S.M Sze, P h ysics o f S e m ic o n d u c to r D evices, 2nd ed., Wiley Eastern Ltd., N e w Delhi, 1985 various dip times T h e R a m a n sp e c tru m o f a Z n S thin film deposited from the re ac tio n b a th s o lu tio n w ith Z n/S - I: ■ the d ip tim e o f h is s h o w n in Fig T hc ballds m R a m a n s p e c tru m can b e e n tir e ly e x p la in e d as follows E j m o d e s at - 140 c m a n d - cm \ transversal [10] S.S Ballard, J s B ro w d e r and J.F Ebersole, in: D.E Gray (Ed.), A m e r ic a n In stitu te o f P hysics H andbook, 3rd e d „ M c G w -H ill, N Y , 1972 [11] A u Ubale, D K Kulkami, Bulletin of M aterials S c ien c e (2 0 ) 3-47 HYDROTHERMAL SYNTHESIS OF CuS HOLLOW SPHERES FROM COPPER NITRATE AND THIOUREA P h u n g O u o c B a o \ K h u c Q u a n g D a t 2, B e X u a n H o p D e p a r t m e n t o f P h y s ic s, H a n o i University o f Sciences, V ie tn a m N a tion a l U niversity, Hanoi 334 - N g u y e n T r a i R o a d , T h a n h X u a n Distr., H a n oi, V ie tn a m ; E m ail: b a o p q @ v n u e d u D e p a r t m e n t o f C h e m i s t r y , H a n o i U nive rsity o f S c ien c es , V ie tna m N a tio n a l U niversity , Hanoi ABSTRACT E X PE R IM E N T A L PR O C ED U R E Without th e u s e o f a n y e x tr a su rfactant, tem plate or other additive, s y n t h e s i s o f h o l l o w sphe res C u S has been realized j u s t v ia h y d r o t h e rm a l trea tm e n t o f complex C u ( N j ) H a n d th io u re a ( N H C S N H 2) in water at ° c for 4h W h e n i n c re a s in g the reaction temperature, m u c h s m a ll e r h e x a g o n a l C u S generated from copper (II) - t h io u r e a c o m p l e x fo rm ed and self­ assembled into hollow sp h e re s S can electron 'microscopy ( S E M ) w a s u s e d t o in v es tig a te the different morphology o f the s y n t h e s i z e d p ro d u c ts X -ra y p o w d e r diffraction ( X R D ) w a s a p p lie d to chara cte riz e the properties o f the o b t a i n e d p r od uc ts A possible mechanism is also d isc u sse d Keywords: C o p p e r m o n o s u l f id e , C u S h o llo w spheres, hydrothermal synthesis IN T R O D U C T IO N As an im p o r ta n t s e m i c o n d u c t o r m aterial, copper monosulfide ( C u S ) h a s r e c e iv e d a great deal o f attention due to its u n i q u e p h y sic al a nd chem ical properties [ -4 ] a n d n o t a b l e a p p lic a tio n s such as solar radiation a b so r b e r [4], c ataly st [5], c oating on the polymer surface to in c r e a s e its c o n d u c tiv ity [ ], high capacity c a th o d e m a t e ri a l in lithium se c o ndary batteries [7], and n a n o m e t e r - s c a le sw itc h es [8 ], thermoelectric c o o lin g m a te ria l [9], optical flier [10], optical record ing m a te ria l [ 1 ], solar cell [ ], and superionic m aterial [13] Efforts h a v e th e r e f o r e b e e n m a d e to prepare inorganic h o l lo w s p h e r e s , g e n e lly in v olv ing the direct synthesis o f in ta c t in o rg an ic shells aroun d sacrificial t e m p la te s , i n c l u d i n g po ly sty ren e latex spheres [14], silica s p h e r e s [15], liquid d ro p lets [16], and m icroem ulsion [17] It a lw a y s have to use solidstate reaction o f e le m e n t s , so lid-state m eta the sis, and self-propagating h i g h - t e m p e r a t u r e synthesis Recently, as in [18], C u S h o l l o w s p h e r e s w e re h y d ro th e rm a lly synthetized with C 11S O H O a n d th io u re a as starting All c he m ic a ls used in this w o rk were analytical re ag e nt grade from c o m m e rc ia l m ark et without further purific ation In a typical pro c ed u re , C u ( N i ) : - H ; (1 mmol, 0.24 g) and th io u re a ( 1.7 m m ol, 12 g) were dissolved, each in ml w a ter to form clear solutions under c on stan t stirring T h e n solutions were m ixe d slowly; a w hite precipitate w a s form ed, w hich was then transferre d into a m l T eflon lined auto clave and m a in ta in e d at ° c for 24 h After cooling to room te m p e tu re naturally, the o btained blue-black products w ere filtered, w a sh e d with distilled w ater and absolute ethanol several tim e s a n d dried at ° c for h T h e phase and pu rity o f the as-prepared products w ere e x a m in e d by X -ray P o w d e r diffraction (X R D ) data w ere c ollected on a S ie m e n s D 5005 diffracto m ete r with C u - K u radiation, 20 r a nging from 10 - 60° The step size was 0.03° and the count tim e was Is S c a n n in g electron m ic ro sc o p y ( S E M ) im ages were taken with a J E O L JS M - 5410 LV scann ing m ic ro sc o p e D IS C U SS IO N Fig I s h o w s the X R D patterns o f the obtained p rod uc ts via h y d r o th e r m a l trea tm e nt at 160°C; ] 80°C; 0 ° c C u ( N j ) ' H ; a nd thiourea ( N H ị C S N H ị ) in w a ter for 24)1 AI ] p e a k s can be indexed as hexagonal phase C uS with lattice c onstants o f a = 3.790 Ả, and c = 16.37 Ấ, w hich are in g o o d a g ree m e n t with the values re porte d in the literature ( JC P D S C ard 78-0876, a = 3.796 Ấ, and c = I 6.38 Ả ) materials H o w e v e r , t o o u r k n o w l e d g e , syn thesis o f CuS hollow s p h e r e s w ith p re c u r s o r s C u ( N ) H j and thiourea by h y d r o t h e r m a l m e t h o d h a v e not been reported In this stu d y , CuS w ith th e sha p e o f ho llo w spheres have b e e n p r e p a r e d b y t r e a ti n g C u ( N ) ị H ; and thiourea from ) ° c to 0 ° c for 24 h 768 Fig X R D p a tte r n s o f the sa m p le s s y n th e tize d at va rio u s h y d ro th e r m a l tem p era tu res Proceedings o f the I” IWOFM ference, Halong Vietnam, December 6-9 2006 T h e S E M im a g e s o f the s a m p le are s h o w n in F ig a W e can clearly see th at the a s- p r e p a r e d C u S fo rm s as po lycry sta llin e h o l lo w s h a p e d spheres (b) F ig S E M im a g e (a) a n d m a g n ifie d S E A f im age (b) o f th e sa m p le h v d r o th e r m a lly s v n th e tiz e d a t 181/ c F ro m a m a g n i f i e d S E M im a g e (Fig 2b), the a verage d i a m e te r s o f the C u S sph e re and the interior hole are c a lc u la te d to be a n d |im , respectively Careful o b se rv a tio n s h o w s that th e surfa ce s o f these s phe res are c o n s t r u c t e d w ith m a n y n a n o f la k e s h aving the a v e g e w id th o f - 150 nm Fig s h o w s S E M im a g e s o f the p ro d u c ts prepared at ° c , ° c , or 0 ° c O n l y n o n - h o l lo w spheres and irregular m o r p h o lo g i e s are o btained , even though the reaction t im e w a s i n c re a s e d to 72 h It is therefore believed that the o p tim a l h y d r o th e r m a l c o ndition for the sy n th e sis o f C u S h o l lo w sp h e re s built by n a n o fla k es is at 18 ° c for 24 h F o r c o m p a r is o n , a se ries of sim ila r e x p e rim e n ts w e re a ls o d o n e at d if f e re n t t e m p e tu re s to d e te rm in e the p o ssible i n f lu e n c in g factors on the pre p ara tio n o f C u S h o l lo w sp h e res W e think that the chem ical re ac tio n b e tw e e n C i i( N )t a n d th io u re a m ig ht be c rucial in the fo rm a tio n o f th ese p e c u lia r shapes In fact, w h e n t h io u r e a is s u b s ti t u te d with o th e r sulfur s o u rc e, such as s o d i u m su lfid e , su lfur p o w d e r , or s o d iu m th io s u lfa te, n o h o l l o w sp h e r e s are o b taine d u n d e r the sa m e c o n d itio n s 769 (c) F ig S E M im ages o f the sa m p le s h y d ro th erm a l!y sy n th e tize d at i - l f f c ( a ) : 16( f c ( b): 0 °c (c) Sm aller CuS n a n o fla k es m ay be form ed at the beginning stage o f h y d ro th erm al trea tm e nt co p p er ( I I ) thiourea c o m p le x at 180cc for 24 h, b e ca u se thio urea can de co m p o se into H ;S as follo w s [IS]: NM:CSNH; + H20 -> NHj + H,s +C0 N H + H : -> N H 4OH C u(N 03 )2 + N H 4O H —> C u ( O H ) : + N H N C u ( O H ) + N I I j O H - > C u ( N H ) ^ + H “ + H 20 Proceedings o f the ” IWOFM - 3rd IWONN Conference, Halong Vietnam, Decem ber 6-9, 2006 s NH il I| h 2n - c - n h References h2 n - c - s h s II [1] S E ro k h in a , V E r okh in, L an g m u ir 19 (2 003 ) 766 [ ] M Inoue, c C r u z -V a z q u e z , J M a ter Clicm {1992) 761 NH II [ j ] J Janata, M Jo s o w icz , C h e m 6 ( 9 ) 207R H2N - C - N H + O H “ H2N - C - O H + SH~ D.M D evaney Anal [4] R s M a n e , C.D L o k h an d e , Mater Chem Phvs 65 (2000) [5] S.Ya K u c h m ii, A v K orzhak, Theor Exp Clicm ( 0 ) ] Cu(NH )] + + S H " - > C u S I + N H ; [ ] M H K unita, E ,M G irotto , Appl Surf Sci ( 200 2) 223 The p ro d u c e d N H w h ic h is m o r e solub le and form NH4OH, after that N H O H act C u ( N ) to pro duce Cu(NHjh2+, w h ic h act w ith S H ' f o rm ed CuS nanoflakes T he p r o d u c e d C O w h ic h is insolub le in water can p r o b a b ly form g a s e o u s cavities un der hydrothermal g r o w th c o n d itio n s, w h ic h can act as heterogeneous n u c le a tio n c e n te r s fo r single bubble growth or p oly cry s ta llin e a g g r e g a tio n A s a result, the freshly formed C u S n a n o f la k e s m ig h t se lf-assem ble around the h o llo w sp h e re s b y the c e n t e r o f the b u b b les under hydrotherm al c o n d itio n s M u c h w o rk is needed to know the exact m e c h a n i s m , a n d so m e correlative studies are underw ay C O N C L U SIO N S In su m m ary, a s im p le h y d ro t h e r m a l ro ute has been developed to o b ta in CuS h o llo w spherical superstructures th r o u g h the re a c tio n o f C u ( N O j) ; and thiuorea in w ater at r e la tiv e ly low tem p e tures The results sh o w that the re a c tio n te m p e tu r e is o f importance in th e fo rm a t i o n o f h o l lo w spherical superstructures Due to th e stability o f the microemulsion sy s te m , th e sim p le strate gy m ay provide p ro m is in g a p p li c a t io n in the syn thesis o f other semiconductor n a n o cry sta ls 770 202 [7] J.-S C h u n g , H.-J Sohn , J Po w er Sources 108 ( 0 ) 226 [ ] T S a k a m o to , H S u na m u H Raw aura, Appl Phys Lett 82 ( 0 ) 3032 [9] T O l i v e r s , J Ch em Soc Dalton Trans, (1996) 185 [10] H T oyoji, H, Y ao, Jpn Kokai T o ky o Koho JP 02 173 622 [11] F M o n g e lla z, A Fillot J.Dc Lallcc, Proc SPIEINT Soc Opt Eng 156 (1 994 ) 2227 [12] S.T L a k s h m ik v m a r, Sol Encruy Mater Sol Cell ( 9 ) [13] A.A K o rz h u e v , Fiz Kliim Obrab M ater (1 93) 131 r14] M L Breen, A.D D on sm ore, R.H Pink, s o Ọadri, B.R Ratna, L a n g m u ir 17 (2001) 903 [15] K.p Veliko v, A van Blaadcren, L an gm u ir 17 ( 001 ) 4779 [16] J I lu a n c , Y Xie, n Li, Y Yin, Y Qian, s Z hang, Adv Mater 12 (20 00) 1518 [17] c Fowler, D K hushalani, s M ann, Client Coin m un ( 0 ! ) 2028 [18] X Ch en, W a n e , X W ane, R Zhanti, X Liu \v Lin, Y Q ia n, Cr>'slal G ro w th 263 (2004) 570 Proceedings o f the Is' IWOFM - y d 1WONN Conference, H along, Vietnam, D ecem ber 6-9 2006 SOL-GEL SYNTHESIS OF MICROCRYSTALLINE ZnO THIN FILMS ON GLASS SUBSTRATES P h u n g Q uoc Bao K h u c Q u a n g D a t 2, K h u a t T h i T h u H i e n D e p a r t m e n t o f P h y s ic s, H a n o i U n iv e rsity o f S c iences, V ie tn a m N a tion a l University, Hanoi 334 - N g u y e n T r a i R o a d , T h a n h X u a n Distr., Han oi, Vietnam ; Email: b a o p q f iiv n u e d u D e p a rt m e n t o f C h e m i s t r y , H a n o i U nive rsity o f S c iences, V ie tna m National University Hanoi A BSTR AC T T h e m ic r o c r y s ta llin e Z n O r epeating the sp i n - c o a t i n g p ost-deposition h e a t - tr e a tm e n t 0 ° c for 3h W h il e the sol su c c ee d ing ly the final h eat-treatm ent (postheaiing) for the Z n O films p reparation film s are p re p a re d by sol-gel process and at 0 ° c , 0 (1c and d i a m e te r e stim a te d by T E M w a s a b o u t 25 n m , the c ry sta llite size o f the Z nO films w a s in the n g e o f 50 - 80 nm d e p e n d i n g on the deposition process X - r a y d iff r a c tio n patterns ( X R D ) indicate that the Z n O film s h a v e a polycry stalline hexagonal w u rtz ite structure T h e optical transm itta n ce was m ain tain ed a b o v e % in v isible regio n, a sharp a bsorptio n e d g e is e x h ib i t e d at the w a v e le n g th o f about 370 nm c o r re s p o n d i n g to the b a n d g a p o f 3,54 eV The p h o to lu m in e s c e n c e ( P L ) sp e c tra s h o w the difference be tw een o n e -la y e re d Z n O film s a n d m ulti-la yere d ZnO films K e y w o r d s : Z n O , Z in c o x id e thin film s, so] gel process, spin-coating IN T R O D U C T IO N Z n O is an i n e x p e n s iv e n -ty p e se m ic o n d u c t o r with a wide b a n d g a p o f 35 e V w h ic h crystallizes in the h e xagonal w u rtz ite struc ture , and a large exiton b onding e n e rg y (6 m e V ) [ I , 2], T h in films ot Z nO with the c - a x i s o r ie n ta tio n p e r p e n d i c u l a r to the substrate s h o w p i e z o e l e c t r i c p r o p e rt i e s and are useful in surface a c o u s tic w a v e d e v i c e s ( S A W ) , bulk acoustic wave d e v ic e s ( B A W ) , m ic r o e le c tr o n ic m ec han ic al system ( M E M S ) a n d a c o u s ti c - o p t i c d e v ic e s [3, 4] T r a n s p a r e n t n - t y p e Z n O thin films d o p e d Fe, C o or Ni sh o w g o o d f e r r o m a g n e t i s m [5] a n d d o p e d Al, G a, In show good e le c tr ic a l c o n d u c t i v it y [ ], Intensive research h a s b e e n f o c u s e d o n fa b ric a tin g I D Z nO na n o stru ctu res a n d in c o r r e l a t i n g th e ir m o rp h o lo g ie s with their siz e - r e la te d o p tic a l a n d e lectrical p rop erties [7] F u rth e r m o r e , Z n O is b i o - s a f s a n d biocom patiblfi and m a y b e u se d for b i o m e d i c a l a p p lic a tio n s without coating T h e Z n O th in film s h a v e b e e n p re p a re d by a wide variety o f te c h n i q u e s , e v ap o tio n , chem ical i n c l u d i n g spu tterin g, reactive vapor d e p o sitio n , spray pyrolysis , sol-ge l p r o c e s s [ - ] In this w o r k , w e h a v e e a r n e d out the re p ea te d s p in - c o a tin g a n d preheat-treatm ent (p re h e a tin g ) and 771 E X PE R IM E N T A L PR O C ED U R E All chem icals used in this w ork were analytical re age n t grade from c om m e rc ial m arket without further purification Firstly, l l g o f zinc acetate d ihydrate Z n ( C H i C O O ) ^ H i O was dissolved in 50ml methanol C H O II and the solution o f 0.1 M was prepare d T h e n a suitable amount o f triethylaminc was a dded After centrifugin g the solution at 3,5 00rpm for 0m in , we o btaine d a d e a r and h o m o g e n e o u s sol solution, which served as the c o atin g solution As substrates, glass plates 20x20x1 n u n in si/e were c le an e d with m ixture o f floride acid and distilled w ater (ratio 1:10) in an ultrasonic bath T h e y were then c le an e d twice again with distilled water and with a ce to ne in that bath, and finally dried in the air Afte r setting the substrate on the disk o f the spin-coater, the coating solution a pprox ml was d r o p p e d and spin-c o ated with 1,000 rev.mill for 15 s in cold room ac and relative hum id ity 0% The wet film w as dried in air for a pe riod o f tim e, and then p re-f ired ill an electric furnace at 0 nc for lh with a h e atin g rate o f a bou t 140°C/Ti be fore a n o th e r coating cycle, if any T h is p r e h ea t-tre atm e n t d e c o m p o se d the p r e c u r s o r Him and o x id iz e d it so as to p ro d u c e ZnO film Z n O thin films from this solutio n were postheateđ at va rious tem peratu res Z n O thin film s from the 5M so lutio n were also pre p are d in the sa m e pro c edu re T n s m ittin g ele ctron m ic ro sc o p y ( T E M ) images o f sol in the so lutio n 0, IM was m e a s u re d by a JK OL JE M -1010 transm ittin g m ic ro sc o p e with the a cc ele ratio n electric potential o f 0kV , resolution o f A a nd 300 m es h es copper grid X -ray diffraction ( X R D ) data w ere c o lle cted on a S I E M E N S D 5005 d iffrac to m e te r with C u K a radiation, 20 r a nging from 10 - 60° T h e step size was 0.03° a n d the count tim e was Is S c a n n in g e le c tro n m ic ro sc o p y ( S E M ) im ages were taken with a J E O L J S M - 10 LV sc a n n in g m icro sco pe T h e o ptical tran s m iss io n and a b so rp tio n spectra o f the ZnO films was m e a su re d by a U V - V I S d o u ble beam s p e c tro p h o to m e te r S H I M A D Z U u v 1650PC The ph o to lu m in e s e e n c e (P L ) sp e c tra at ro om tem peratu re were m ea sure d by a J O B I N - Y V O N sp c c tr o f lu o r o m e te r FL 3-2 with the excited w a v e le n g th o f 325 nm Proceedings o f the I s' IW O F M -3 rd IfVONN Conference, Halong, Vietnam, Decem ber 6-9, 2006 RESULTS AND DISCUSSION TEM im age o f sol in the precursor solution w as taken and disp layed in F ig O n e can se e black sol particles with spherical form s o f about 25 nm diam eter 0 c a n d 500°c for 3h T h e n u m b e r o f peaks and their intensities in cre as e w ith incre asing the postheating t e m p e tu re All p e a k s c an be indexed as hexagonal p se Z n O w hich are in goo d agreem ent with the sta n d ard va lu e s r e p o rte d in the literature Fig / TEM im age o f so l in the ] M c o a tin g solu tio n Fig show s th e S E M p h o t o g r a p h s o f the surface of ZnO films p re p a r e d b y r e p e a ti n g the spin-coating (0 M solution) a n d p r e h e a t- t r e a t m e n t at 200"c for Ih and by postheating at 500°c T h e m e d i u m particles diameter for the o n e -la y e r e d Z n O film is a bo ut 50nin It is found that the p a rtic le siz e in the five-layered Z nO film is larger than th at in th e o n e - la y e r e d Z n O film The thickness and the p a r tic le s size m ig h t b e controlled by either the p re c u rs o r so l u t io n c o n c e n tr a tio n or the number o f c o atin g c ycles Fig X R D p a tte r n s o f Z n O film s d e p o site d w ith the M c o a lin g so lu tio n a n d p o s th e a te d a t various tem p e tu re s T h e (100), (1 01), ( 0 ) and (] 12) diffraction peaks were o b se rv e d in the X R D pattern co rre sp o n d in g to the posth e ating te m p e tu re o f 0 'C W h en the firing tem p e tu re was in creased to 0 ° c , (103) diffraction peak a p p e a r e d , the intensities o f ( 0 ) and ( 1 ) diffraction p e ak s increased At 0 ° c , (102) and (1 10) diffraction peaks a p p e a r e d , and all the peaks intensities m o re p ron o u n c ed As com m on!)' reported, the sol gel derived Z nO polycrvstalline films sh o w ed the pre d om inan tly high (002) peak in the X R D patterns, indicating the c-axis preferential orientation o f the films crystallites Bui it was not the c ase in the o btaine d Z n O thin films, in sistence with the large half-width o f diffraction peaks, s u c g e s tin c their nanocrystallite structure The average p article sizes c alculated by the Shcrrer equation for the Z n O films po sth e ated at 0 oC, 0 r‘c and 0 nc were a b out nm, 78 nm and 90 nm, respectively T h e s e values are in reaso nab le agreem ent with the p articles sizes estim ated in the related SE M images Fig show s the typical optical transm issio n spectrum o f the a s-p re p a re d Z n O films High optical tran sm ittan ce is m ain tain ed a b o v e % in visible and near IR regions T h e visible range with a sharp (b) absorp tion ed g e at w a v e le n g th o f a bo ut 370 nm c o rre sp o n d s to its b a n d g a p o f 3,54 eV T his b a n d c a p Fig The SE M p h o to g p h s o f the s u r fa c e o f the Z n O films prepared with (a) one co a lin g cycle an d (b) fiv e coaling cycles fo llo w e d by p o sth ea lin g a t 0 °c Fig s h o w s the X R D p a tt e rn s o f Z n O films prepared by the sam e proced ure w ith the ,5M coating solution fo llo w ed by postheat-treatm ent at 300 c , 772 value is a bit larger than that o f Z n O crystal (3.3 eV) T his p h e n o m e n o n can he e xpla ined by the existe nce o f grain b o un da rie s and im p e rfec tio n s in polycrystalline thin films T h e a tom ic structu re at grain b o un da rie s is different from that in the grain , w hich leads to higher free carrier c o n c e n tr a tio n s and the oc cure nce of Proceedings o f the r I W O F M - y “ IWONN Conference, Halong, Vietnam December 6-9, 2006 potential barriers at the boundaries and the formed electric field m akes the bandgap larger The w eak fluctuation in the transm ission spectrum is due to the interferences in the thin film o w in g to the reflection at band for the five-lay r d Z n O films is very stronger than that in the p h o to lu m in e s c e n c e spectrum o f the one-layered Z n O thin films indicates the hom ogeneity o f as-deposite d m ulti-la yere d films the air-ZnO and Z nO -glass interfaces T h e high optica] transmittance and the high bandgap energy allo w the C O N C L U S IO N ZnO film s to be suitable for m any a p p lic a tio n s in display d evices Fig T y p ica l o p tic a l tra n sm is sio n sp e c tr u m o f the a s-p rep a red Z n O f il m s W e have presented the pre para tion o f Z n O thin films by sol-gel process using zin c acetate dihydrate, methanol and trie thyla m ine as the starting materials The multi-layered films have b een carried out by the repeated spin - coating and preheat - treatm ent {preheating) and su c c ee d ing ly the final heat-treatm ent (postheating) W hile the sol have spherical form with the typical d iam eter o f about 25 nm, the average particles size varies about 50 - 90 nm, d e pen ding on the coating solution c oncentration, the n u m b e r o f coatinc cycles and the posth eating tem perature X R D patterns suggest the m icrocrystallite structure o f the obtained films T h e Z n O thin films are transparent in visible and near IR regions with optical transm ittance o f m o re than 90% The typical b a n d g ap is about 3,54 eV I f the p ho tolu m in csce nce spectrum o f m ulti-layered films is similar to that o f Z n O p ow der, the o ne-lay ered films exhibits emission ban ds at 375 nm, 410 nm, nm, and one large green band at 480 nm, indicating the imperfect crystalline structure o f these films with microcryslallite m o rphology Further investigations will be focused on the control o f the m ic rocrystallites size in the sol-gel deriv ed Z n O thin films R eferen ces [1] Tiwaii A., Jin c , Kuit A,, K u m a r D., M uth J.F., Narayan J., Solid-State C om m un ( 0 ) 121:371 [2] Tang Z.K., Yu p., W ong G.K., Kaw asaki M., O h tom o A., K o in u m a H., et al., Solid-State C om m un (1 997 ) 103:459 [3] M.S W u et a l I E E E T rans Ultra Ferro Freq Fig P h o to lu m in e s c e n c e s p e c tr a o f o n e -la y e r e d (re d line) a n d f iv e -la y e r e d (b la c k lin e ) Z n O th in film s The p h o t o lu m i n e s c e n c e sp e c tr u m of the one-layered Z n O thin film s p r e s e n t e d in Fig conta ins em ission bands at 375 nm (correspond ing to 3,31 eV - exciton nm As radiation for the photolum inescence energy), nm , nm, and 480 five-layered s p e c tr u m ZnO c o n s is ts of Contr 36 (19 ) 442 [4] s c M inn e et al Appl Phys Lett 67 (26) (1 995 ) 3918 [5] H J Lee, s Y Jeong, c R C h o , c H Park A pplied Physics Letters 81 ( 0 ) -4 2 , [6] Jiang H.Q., W a n g L X., Z h a o s M., Hui c , Journal o f Functio nal M aterials 31 (2 0 ) 278-280 [7] A m elao L., Fab rizo M., G ia la n ella s , Z o rdan F., Thin Solid Films (2 0 ) 89-95 film s, the [ ] D.G Baik, S.M Cho, T h in Solid Films 35 (19 99) only two 2 - [9] Y Natsum e, H Sakata, T hin Solid Films 372 emission bands centered at 375 nm and 0 nm, sim ilar to that o f Z n O p o w d e r T h e c h a r a c te ris tic g re e n b a n d is shifted towards shorter w avelen gth s, from 510 nm for ZnO pow der to 500nm for the five-layered ZnO film s and to run for the on e-layered ZnO thin film s One can say that the sm aller the particles siz e , the m ore the photolum inescence green band sh ifted tow ards shorter wavelengths T he fact that the intensity o f the exciton 773 (2000) 30-36 [10] A, Mitra, R K T h a r e ja et al., A p p lied Surface Science 174 (20 ) 232 -2 I’llIIvi; ĐĂKG KÝ IíỂT QUẢ ỈVGHIÊiV cứtr K H O A H Ọ C — CÔ STG K G H Ề -9 ■ f• -* Tên đ ề tà i: n g h i ê n u đ ề tà i tổ n g h ợ p vật liệu nano m n g m ỏng M ã số: Q T -0 -2 C q u a n ch ủ trì đ ể tà i: T r n g Đ ại h ọc K h oa học Tự nh iên - Đ H Q G H N 3 N g u y ễ n Trãi, T h a n h X uân, Hà N ộ i Tel: 84 87 T ổn g k in h p h í th ự c ch i: 0 0 (M òi triệu đ ồn g chẩn) T r o n g đó: T h òi g ia n th ự c h iện : -T ngân sách nhà nước: 0 0 0 đ - K inh phí trường: đ - V a y tín dụng: đ - V ố n tự có: Od - Thu h i: Od ] th án g Thời gian bắt đầu: /2 0 T hời gian kết thúc: 10/2006 Tê lì cán p h ố i h ợ p n g h iên cứu: Sỡ đ n g k ý đ ê tài: Ngày: P h ù n g Q u ố c Bào, D V ã n H i ệ p P h m T r u n g H o n g Sơ ch ứ ìĩg nh ận đ ă n g k ý k ết q u ả n g h iê n c ứ u : B o m ậ t: a P h ổ b iến lộ n g rãi: b P h ổ b iế n h n chế c B o m ật X Tóm tắt kết nghiên cứu: Đ ã tìm quy c h ế tạo trình tạo nano xốp lổ trung bình MCM-41 đảc trưng xốp bề mặt chúng : kích thuớc cấu trúc lỗ, diện tích bề mặt Đã tìm quy trình chê tạo màng perovskit bề mặt lỗ xốp cùa MCM-41 băng phương pháp tâm, đặc trưng xốp bề mặt chúng : kíchthước cấu trúc ỉỗ, điện tích bề mặt, đặc trưng hấp phụ hoá học c o Đã tim đặc trưng xử lý c o HC khí thải động hệ xúc tác LaxSrj.xF e yCo,.y0 v vai trò ảnh hưởng Fe Co Đã tìm quy trình tổng hợp đặc trưng CuS dang cầu rỗng từ nitrat thioure phương pháp thuỷ nhiệt Đã tìm dược quy trình tổng hợp màng mỏng vi tinh thể ZnO bàng phương pháp sol-gel tìm hiểu số đặc trưng chúng : XRD, SEM, huỳnh quang Đã tìm q u y ,trình tổng hợp màng mỏng ZnS phương pháp CBD s ố đặc trưng chúng: XRD, SEM, R am an , í T M T ln ) trò n g c q u a n c h ù trì đ ề tời C h ủ n h iệ m đ ề lài C h ủ tịch H ộ i d ó n g đ n h giã T h ù trâ n g c q u a n q u n ly c h ín h thứ c đ ẽ lài -r- H ọ v rên K húc Q u an g Đạt ? -T) C ' Ịỉ^C ị /ù j,l/g Ị l ì s ý i H ọc hàm , học vị ^ Cn í% i r H U j ỉ* ì ì ỵ * ■* ~\ TBƯỎ' K ỷ lê n , \l V /íỏ / Đ óng dấu ầ ẠI H d p Á ? \ i n A f-i I tịịẦ íỉĩA ^ V\ g Ự W TFN ■ -/ T' : r J ị V nil,d 11~ì* f - ... đề tài: nghiên cứu chế tạo vật liệu nano màng mỏng Mã sô: QT - 05 - 21 b Chủ đề tài: Khúc Quang Đạt c Cán tham gia: Phùng Quốc Bảo Dư Văn Hiệp Phạm Trung Hoàng d Mục tiêu nội dung nghiên cứu -... tiêu: Nghiên cún chế tạo đặc trưng hệ xúc tác LaxSi*ị.xFevCo1.>,03±5 /MCM-4 1và hoạt tính xử lý c o HC khí thải động Nghiên cứu tổng hợp CuS dạng cầu rỗng, màng mỏng ZnO ZnS - Nội dung: Nghiên cứu. .. Hải, Khuất Thị Thu Hiển (Khoa Vật Lý ĐHKHTN-ĐHQGHN) Các kết nghiên cứu để tài đăng báo Hội Nghị Quốc Tế lần thứ vật lý nano vật liệu nano 2006 Hạ Long Các kết' nghiên cứu lại cơng bố liếp tạp trí

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