Đang tải... (xem toàn văn)
In the present work, we have endeavored the utilization of wet-chemically synthesized copper oxide nanoparticles (CuO-NPs) as the active layer in hybrid bulk heterojunction (BHJ) solar cells. The BHJs with CuO-NPs display significantly different physics from customary BHJs, and prove a noteworthy improvement in their performance.
Journal of Science: Advanced Materials and Devices (2020) 104e110 Contents lists available at ScienceDirect Journal of Science: Advanced Materials and Devices journal homepage: www.elsevier.com/locate/jsamd Original Article Utility of copper oxide nanoparticles (CuO-NPs) as efficient electron donor material in bulk-heterojunction solar cells with enhanced power conversion efficiency Hafsa Siddiqui a, b, *, 1, Mohammad Ramzan Parra a, c, 1, Padmini Pandey a, d, M.S Qureshi a, Fozia Zia Haque a, ** a Optical Nanomaterial Lab, Department of Physics, Maulana Azad National Institute of Technology, Bhopal, 462003, India Department of Physics, Sha-Shib College of Science and Management, Bhopal, 462030, India Department of Physics, Govt Degree College Boys Sopore, Jammu & Kashmir, 193201, India d Department of Physics, Savitribai Phule Pune University, Pune, 411007, India b c a r t i c l e i n f o a b s t r a c t Article history: Received October 2019 Received in revised form 18 January 2020 Accepted 23 January 2020 Available online 12 February 2020 In the present work, we have endeavored the utilization of wet-chemically synthesized copper oxide nanoparticles (CuO-NPs) as the active layer in hybrid bulk heterojunction (BHJ) solar cells The BHJs with CuO-NPs display significantly different physics from customary BHJs, and prove a noteworthy improvement in their performance It is noted that with the addition of CuO-NPs, the morphology of the photoactive layer endures significant changes Incorporating CuO-NPs is an additional paradigm for BHJs solar cells which enhances the photocurrent density from 9.43 mA/cm2 to 11.32 mA/cm2 and the external quantum efficiency as well Also the power-conversion efficiency (PCE) improved from 2.85% to 3.82% without harming the open circuit voltage and the fill factor The enhancement in PCE achieved here makes it worthy to design high-performance organic solar cells holding inorganic nanoparticles © 2020 The Authors Publishing services by Elsevier B.V on behalf of Vietnam National University, Hanoi This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/) Keywords: Bulk heterojunction Solar cells Copper oxide nanoparticles Thin films Photo current density External quantum efficiency Introduction Currently, in order to adapt to the rapid development of electronic devices and electric vehicles, various energy storage materials are constantly being designed and developed Bulk heterojunction solar cells (BHJ-SCs) have many advantages such as low cost of fabrication and an easy and simple fabrication process with a wide range of applications They have many tremendous features such as transparency and the possibility of being fabricated in different colors, thus being of interest for building-integrated * Corresponding author Department of Physics, Sha-Shib College of Science and Management, Bhopal, 462030, India ** Corresponding author Optical Nanomaterial Lab, Department of Physics, Maulana Azad National Institute of Technology, Bhopal, 462003, India E-mail addresses: hafsa.phy02@gmail.com (H Siddiqui), foziazia@rediffmail com (F.Z Haque) Peer review under responsibility of Vietnam National University, Hanoi Equal contribution: Hafsa Siddiqui and Mohammad Ramzan Parra made an equal contribution photovoltaics (BIPV) applications [1,2] BHJs comprise of several layers in which the photoactive layer plays a crucial role in enhancing the overall photo-conversion efficiency (PCE or h) The main challenging fact that is highlighted in the literature for BHJSCs is the poor light absorption mainly due to the small exciton diffusion length and short carrier mobility [3] To cover the visible region of the solar spectrum, it requires compounds that strongly absorb this range [4] Therefore, a combination of inorganic nanoparticles with P3HT:PCBM (poly(3-hexylthiophene): phenyl-c61butyric acid methyl ester), have a potential to surpass in better performance while retaining the benefits Inorganic nanoparticles have features as bandgap tunability, high absorption coefficient and high intrinsic charge carrier mobility [5,6] Moreover, previous studies of solar cells that have directly incorporated inorganic nanoparticles as electron acceptors i.e., ZnO, TiO2, or FeS2 nanoparticles, consist of light-harvesting absorbers, or light-scattering centers using Au, Ag or PbS nanoparticles in conjugated polymer films [7e9] Compared to these inorganic nanoparticles, CuO nanoparticles, a photo-generating material, have higher absorption in the visible region and inject excess electrons to the structure https://doi.org/10.1016/j.jsamd.2020.01.004 2468-2179/© 2020 The Authors Publishing services by Elsevier B.V on behalf of Vietnam National University, Hanoi This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/) H Siddiqui et al / Journal of Science: Advanced Materials and Devices (2020) 104e110 [10e12] Much research has been carried out in the field of catalyst, sensor and energy conversion due to the contribution of CuO [13e18] The wide applications of CuO with controllable size, shape, defect and dopant has intensely inspired many researchers The wide-range studies carried out show that the development of cupric oxide (CuO) nanocrystals with modified architectures establishes a relationship between the structure and the properties of CuO and its practical applications [19e22] Hence, the P3HT donor property could be tuned by generating electrons from the CuO nanoparticles M Ikram et al [23,24], E Salim et al [25] and A P Wanninayake et al [26], used commercially available CuO nanoparticles to enhance the PCE of P3HT:PCBM solar cells Here, we have synthesized CuO-NPs (for experimental details see electronic supporting information) by utilizing the wet chemical method and explained there structural, chemical and optical properties and followed the photovoltaic performance by serving them in P3HT:PC70BM in different concentrations (0%, 1%, 3%, 5%, 7%, and 10 wt %) Without the addition of CuO-NPs a PCE of 2.84% has been achieved for P3HT:PC70BM solar cells However, a higher efficiency of 3.82% is effectively achieved for CuO added P3HT:PC70BM because of an efficient excitation generation, better light absorption and a photoexcited charge separation and collection The concept of the CuO-NPs fabrication and the use of them into a P3HT:PC70BM photoactive blend is a noteworthy contribution The systematic study with detailed discussion in the present 105 work is a first contribution towards the full understanding of such a device architecture Experimental All the experimental details are reported in Electronic Supporting Information (ESI) Results and discussion The XRD pattern of the prepared CuO nanoparticles (Fig 1a) confirms the formation of the pure monoclinic phase of CuO as all the marked peaks are well indexed with JCPDS card no 80-0076 In addition, the complete crystallographic information, as revealed through a Rietveld refinement of the prepared sample, is given in the supporting Information The refinement pattern is illustrated in Fig 1b The micro Raman (m-RS) study further supports the microstructural (crystallographic) changes and various defect states present in the prepared sample (Fig 1c) The peak found at 288 cmÀ1 is assigned to the Ag mode, which corresponds to the typical motion of the oxygen atom for displacement in the b-direction of the monoclinic structure of CuO (for details please see [27]) Additionally, two peaks observed at 338 cmÀ1 and 624 cmÀ1 are attributed to the first-order Raman (Bg) modes Fig Characterization of the as-synthesized CuO-NPs (a) XRD patterns and (b) Rietveld refinement of the XRD pattern, (c) Raman spectrum, (d) full-scan XPS spectrum of CuO-NPs and corresponding deconvoluted peaks in the high resolution spectra for Cu-2p (e), and O-1s (f) elements Low (g) and high-resolution (h) TEM images and corresponding particles size distribution is shown in the inset, and SAED pattern with all diffraction rings corresponding to indicate yellow CuO diffraction rings (i) 106 H Siddiqui et al / Journal of Science: Advanced Materials and Devices (2020) 104e110 Further, the XPS survey scan does not include any chemicals other than Cu, O, and C as shown in Fig 1d In addition (see Fig 1e), the core level scan spectrum of Cu2p shows a doublet with peaks centered at ~934.9 ± 0.1 eV and ~954.3 ± 0.1 eV corresponding to Cu2p3/2 and Cu2p1/2, respectively These peaks are accompanied with a set of satellites peaks at 962.2 eV, 941.3 eV and 943.6 eV corresponding to Cu2ỵ state in CuO [28] A spectral deconvolution of the O-1s spectrum (Fig 1f), results in two components appearing at around 531.02 eV and 532.36 eV The binding energy component observed at 531.02 eV corresponds to the O2À ion in the CueO bonds The peak observed at higher binding energy at around 532.36 eV relates to oxygen vacancies in the CuO lattice Moreover, morphological investigations were performed using TEM with low and high magnifications (Fig 1g and f) TEM images of the sample show size, shape and distribution of CuO-NPs as uniform and homogeneous The spherical nanoparticles have a diameter of ca 50 ± nm (see inset Fig 1g) A selected-area of the electron diffraction pattern of CuO-NPs is indexed using C-Spot software The TEM diffraction pattern designates the presence of a single crystal with a monoclinic structure (see Fig 1i) The TEM results are well in accordance with the XRD results Moreover, the optical band gap as well as the absorbance of the as-prepared CuO-NPs is a key factor that has a major effect on the performance of the prepared BHJs The obtained absorption spectrum at ~836 nm corresponds to an energy of 1.47 eV (using tauc relation detail is given in electronic supporting information and Fig S1) and is blue shifted to the visible region as compared to the reported absorption of CuO-NPs with an average particle size of ~50 nm (commercially available CuO-NPs) [23e26] Therefore, a better absorption of visible light is evidence of a better light harvesting The above data confirm the pure phase formation of the prepared CuO-NPs (detailed discussion above) These CuO-NPs were utilized as a photo-absorber in the poly (3-hexyle thiophene) (P3HT) [6]: phenyl-C61-butyric-acid-methyl-ester (PCBM) solar cell device application We were able to achieve a remarkable enhancement in efficiency after inclusion of CuO-NPs The performance of the asprepared CuO-NPs combined P3HT:PC70BM films were initially examined in detail via AFM, XRD and UV-visible spectroscopy The relevant films were spin cast on quartz substrates [29] The nanoscale morphology of pristine P3HT:PC70BM (Fig 2a) and CuO incorporated P3HT:PC70BM films (Fig 2bec) confirm the surface peaks of the CuO incorporated P3HT:CuO: PC70BM which are higher as compared to pristine P3HT:PC70BM and infer an obvious increase in surface roughness due to the addition of CuO-NPs The rootmean-square roughness (RMS) value increased from 0.711 nm to 4.188 nm as the addition of CuO-NPs increased from to 10 wt% The cell containing wt% of CuO-NPs shows a surface roughness value of 2.402 nm, because of an increased nanoscaled phase separation concerning the crystalline P3HT and the PC70BM acceptor [30,31] However, the surface roughness of the film which contain 10 wt.% of CuO may also increase the structural defects such as micro-cracks (see Fig 2c) which act as active recombination centers lead to increase the series resistance and lowering the Jsc an Voc values Optimal surface roughness gives more room for P3HT to form, thereby increasing crystallinity Furthermore, it can increase the interfacial contact area between the PEDOT:PSS and P3HT:CuO:PC70BM layer, allowing an efficient gathering of holes at the anode and thereby improving current density (Jsc) The incorporation of CuO to the P3HT:PC70BM also affects the P3HT crystallinity as supported by the XRD results (Fig 3a) The addition of copper nanoparticles can improve the crystallinity of P3HT [24] The observed increase in crystallinity of the P3HT state seems to be partially accountable for the rise in the absorbance and PCE of the devices [23] The Uv-visible absorbance spectra of pristine P3HT:PC70BM and CuO incorporated P3HT:PC70BM (Fig 3b) show Fig 2D and 3D topographical AFM images of (a) pristine P3HT:PC70BM, (b) wt%, and (c) 10 wt% CuO-NPs incorporated P3HT:PC70BM photoactive layer H Siddiqui et al / Journal of Science: Advanced Materials and Devices (2020) 104e110 two absorption zones The first zone below 350 nm was recognized as PC70BM molecules while the absorption spectra from 350 nm to 650 nm (second zone) are related with poly (3-hexylthiophene) (P3HT) The peak obtained at ~500 nm can attributed to the pep* transition The region below the absorption peak shows the light harvesting ability of the photoactive layer [30] The obtained peak has exhibited a red shift ~510 nm after the incorporation of CuO-NPs, because of the interruption of the structure and the orientation of chain ordering of P3HT due to the CuO-NPs ability of light capturing In CuO incorporated photoactive layer blend, the absorption area is enhanced from visible light to the near infrared area The absorption is enhanced by the increasing amount of CuO nanoparticles in the active layer (Inset Fig 3b) Further, the performance of the as-prepared CuO nanoparticles in P3HT:PC70BM solar cell was examined The complete procedure of device fabrication and testing as well as cell parameters is provided in the supporting information The fill factor (FF), short circuit current density (Jsc), open circuit voltage (Voc), power conversion efficiency (PCE) and other related parameters were calculated using the formulas as reported in refs [32,33] and a detailed comparison of cell parameters is presented in Table As earlier reports on the OPV have proven, the active area and active layer thickness is directly related to the power conversion efficiency (PCE) [34] The assembly of the organic photovoltaics based P3HT:PC70BM that was utilized in this research is shown in Fig 4(aeb) We have tried a possible modification in the conventional architecture of [35] P3HT:PC70BM solar cell by a successful incorporation of precisely synthesized pure CuO nanoparticles The possible band alignment of pristine P3HT:PC70BM blend and CuO incorporated P3HT:PC70BM ternary blend are presented in Fig 4(ced) and are well supported by the available literature [35] Short circuit current density versus open circuit voltage (J-V) characterization (Fig 4e) of pristine P3HT:PC70BM solar cell has been achieved with an ~2.85% efficiency From Table 1, it is obvious that after the incorporation of CuO-NPs, Jsc increased from 9.43 mA/cm2 to 11.32 mA/cm2 This indicates that the properties of the CuO-NPs affect the Jsc of the device as well Device parameters such as Jsc, Voc, and FF show increasing behavior up to a certain (5 wt%) composition and then decrease beyond this concentration The power conversion efficiency follows the same trend, increasing from 2.85% to 3.82% and then decreasing with further addition of CuO which may be due to a higher aggregation of the CuO [8] The aggregates let the solar cell structure collapse and remove the network for charge collection Wanninayake et al (2015) reported on the P3HT:PCBM solar cell with CuO nanoparticles and obtained a value for the PCE of ~2.96% [26] In comparison with reported CuO incorporated P3HT:PC70BM solar cells, our findings are novel and better because of the utilization of a cost effective synthesis method for preparing CuO-NPs and by serving them as photo absorber for achieving enhanced power conversion efficiency Also, it is our belief, that this is the maximal reported PCE based on a CuO incorporated P3HT:PC70BM solar cell In respect to device architecture, it is the most desired approach for improving the absorption as well as Jsc of the prepared devices Further, the obtained results were compared with the reported P3HT:CuO:PC70BM solar cell (normal configuration) values and are summarized in Table The effect of CuO-NPs inclusion is fairly well observed in the series and shunt resistances as revealed from Fig S2 The series resistance (Rs) was 46 U for pristine P3HT:PC70BM With an increase in the CuO-NPs concentration to 5.0 wt %, the series resistance (Rs) decreased to 11 U Similarly, the maximal shunt resistance (Rsh) was observed for P3HT:CuO5wt%:PC70BM, indicating a reduced electronehole recombination rate and a leakage current due to the presence of CuO-NPs [36] The CuO-NPs may create a network which can efficiently dissociate the exciton which results in the 107 Fig (a) The X-ray diffraction patterns of pristine and CuO-NPs incorporated P3HT:PC70BM films (b) The UV-Vis absorption spectrum of pristine and CuO-NPs incorporated P3HT:PC70BM films, Inset enlarged x-axis in range 540e800 nm Table Comparative analysis of device parameters of CuO incorporated P3HT:PC70BM solar cell with pristine P3HT:PC70BM solar cell Fabricated devices Voc (V) Jsc (mA/cm2) FF (%) PCE (%) P3HT:PC70BM P3HT:CuO1wt%: PC70BM P3HT:CuO3wt%: PC70BM P3HT:CuO5wt%: PC70BM P3HT:CuO7wt%: PC70BM P3HT:CuO10 wt%: PC70BM 0.56 0.57 0.58 0.59 0.56 0.52 9.43 10.24 10.84 11.32 10.11 6.38 54.01 56.92 56.12 56.76 52.55 44.96 2.85 3.43 3.53 3.82 2.98 1.49 ± ± ± ± ± ± 0.02 0.01 0.03 0.02 0.04 0.02 EQE (%) 38 41 46 50 36 27 higher shunt resistance The shunt resistance (Rsh) falls for higher concentration of CuO-NPs In order to study the light harvesting capabilities of pristine P3HT:PC70BM and CuO incorporated P3HT:CuO:PC70BM devices, external quantum efficiency (EQE) spectra have been recorded (Fig 4f) More photons absorbed in the active layer (P3HT:CuO:PC70BM) is one possible reason for the improved carrier generation The maximal efficiency of the EQE spectra shows the same trend as Jsc and PCE As expected, the cell P3HT:CuO5wt %:PC70BM exhibited an extended photocurrent onset and showed a marked improvement in EQE in the region of 400 nme750 nm, compared to those of remaining (0%, 1%, 3%, 7%, and 10 wt% of CuO nanoparticles) based P3HT:PC70BM devices The maximal EQE of 108 H Siddiqui et al / Journal of Science: Advanced Materials and Devices (2020) 104e110 Fig (a) Device structure (b) Schematic diagram of the device structure (c, d) Energy level diagram of the component materials used for device fabrication using Ref [23e25] (e) Current densityevoltage (JeV) characteristics of pristine and CuO-NPs incorporated P3HT:PC70BM devices (f) External quantum efficiency (EQE) and corresponding integral current of the pristine and CuO-NPs incorporated P3HT:PC70BM devices the P3HT:CuO5wt%:PC70BM device was 50% at 550 nm which is higher than the rest of the devices (Table 1) The higher absorption range from 400 nm to 750 nm for the P3HT:CuO5wt%:PCBM device followed the same trend as the EQE spectra and can be combined with a similar variation of the absorption curve The integrated Jsc calculated from the EQE spectra (Fig Fig 4f) was slightly lower (around 2%) compared to the Jsc value measured in J-V characteristics and shows that the Jsc values are more trusting We Table Few reports were found on CuO incorporated P3HT:CuO-NPs:PC70BM (Based on the Scopus data) till date with different configuration (normal and inverted) of solar cells Author CuO-NPs Cell Configuration Type PCE Ref E Salim CuO-NPs Sigma Aldrich CuO-NPs Sigma Aldrich CuO-NPs Sigma Aldrich CuO-NPs nanocs.com USA CuO-NPs nanocs.com USA Wet chemically synthesized CuO NPs ITO/ZnO/P3HT:CuO:PCBM/MoOx/Ag Inverted 4.1 25 ITO/ZnO/(P3HT:CuO:PCBM/MoO3/Ag) Inverted 4.09 23 ITO/ZnO/(P3HT:CuO:PCBM/MoO3/Ag) Inverted 3.7 24 ITO/PEDOT:PSS (with Au-NPs)/P3HT/PCBM/CuO/Al ITO/PEDOT:PSS/P3HT/PCBM/CuO-NP/Al ITO/PEDOT:PSS/P3HT/PC70BM/CuO-NP/Al Normal Normal Normal 3.5 2.9 3.82 36 26 Present work M Ikram M Ikram A P Wanninayake A P Wanninayake H Siddiqui, M R Parra H Siddiqui et al / Journal of Science: Advanced Materials and Devices (2020) 104e110 consider that the improvement in EQE and Jsc results from the effective light scattering Meanwhile, the FF value (56.76%) of the P3HT:CuO5wt%:PCBM device is high, indicating that the interface between the ITO/PEDOT:PSS and the active layer (P3HT:CuO5wt%:PCBM) keeps a respectable contact quality, which is also reflected by the Rs and Rsh values [4] [5] Conclusion [6] The present piece of work successfully fabricates P3HT:PC70BM solar cells by incorporating wet chemically synthesized CuO nanoparticles to adjust the morphology of the active layer by which a significant enhancement of the device efficiency is achieved It is innovative to adopt wet chemically synthesized CuO nanoparticles as an additive instead of the conventional organic high-boiling compound This is the novelty factor of this work A power conversion efficiency of ~2.85% has been achieved for pristine P3HT:PC70BM solar cells However, a higher power conversion efficiency of 3.82% is effectively achieved for an optimal amount of CuO-NPs added P3HT:PC70BM because of an efficient excitation generation, better light absorption and a photoexcited charge separation and collection It is inferred that the incorporation of CuO nanoparticles into the P3HT:PC70BM blend can efficiently enhance the device performance which is validated by the EQE study as well Additionally, the shift in the absorption spectrum to the visible region would help in a better absorption of light after the incorporation of CuO-NPs in the P3HT:PC70BM blend Such sort of research paves the way to design an easy route for the synthesis of copper oxide nanoparticles Also, P3HT:PC70BM with an enhanced efficiency may be useful for further optoelectronic applications [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] Declaration of Competing Interest The authors declare that they have no conflict of interests Acknowledgments HS is thankful to UGC, New Delhi, India and MPCST Bhopal for the award of MANF (F1-17.1/2011-12/MANF-MUS-MAD-4694) and FTYS (File No: 83/CST/FTYS/2016) MRP acknowledges CSIR, New Delhi for the award of SRF (ack no 163320/2K14/1) Authors would like to thank Director CSIR-NCL, Pune, and are pleased to acknowledge Dr K Krishnamoorthy, Scientist, Polymers and Advanced Materials Laboratory, CSIR NCL, Pune for solar cell fabrication and testing The help rendered by Mr S Chithiravel is highly appreciated Authors are thankful to the Director-UGC-DAECSR, Indore Centre for performing material characterization and grateful to Dr R J Choudhary for providing the XPS facility In addition, authors acknowledge Mr Wadikar and Mr Sharad Kumar (AIPES, Beamline BL-2 Indus-1, RRCAT, Indore) for technical assistance [18] [19] [20] [21] [22] [23] [24] [25] [26] Appendix A Supplementary data [27] Supplementary data to this article can be found online at https://doi.org/10.1016/j.jsamd.2020.01.004 [28] References [29] [1] H Siddiqui, Lead-free perovskite quantum structures towards the efficient solar cell, Mater Lett 249 (2019) 99e103 [2] M.R Lee, R.D Eckert, K Forberich, G Dennler, C.J Brabec, R Gaudiana, Solar power wires based on organic photovoltaic materials, Science 324 (2009) 232e235 [3] C.H Kim, S.H Cha, S.C Kim, M Song, J Lee, W.S Shin, S.J Moon, J.H Bahng, N.A Kotov, S.H Jin, Silver nanowire embedded in P3HT:PCBM for high- [30] [31] 109 efficiency hybrid photovoltaic device applications, ACS Nano (2011) 3319e3325 S Zhang, P.W Cyr, S.A McDonald, G Konstantatos, E.H Sargent, Enhanced infrared photovoltaic efficiency in PbS nanocrystal/semiconducting polymer composites: 600-fold increase in maximum power output via control of the ligand barrier, Appl Phys Lett 87 (2005) 233101 B Sun, H.J Snaith, A.S Dhoot, S Westenhoff, N.C Greenham, Vertically segregated hybrid blends for photovoltaic devices with improved efficiency, J Appl Phys 97 (2005), 014914 W.J.E Beek, M.M Wienk, R.A.J Janssen, Efficient hybrid solar cells from zinc oxide nanoparticles and a conjugated polymer, Adv Mater 16 (2004) 1009e1013 P Yu, S Qu, C Jia, K Liu, F Tan, Modified synthesis of FeS2 quantum dots for hybrid bulk-heterojunction solar cells, Mater Lett 157 (2015) 235e238 A.A.M Velazquez, D Canto-Reyes, J.A Mendez-Gamboa, M Acosta, Optical absorption enhancement of P3HT:PCBM films through nanocavities using polystyrene as a template, Mater Lett 245 (2019) 65e67 H Wang, W Li, Y Huang, Y Wang, S Yang, B Zou, Efficiency enhancement of organic solar cells by inserting PbS quantum dots film as the infrared absorption layer, Mater Lett 187 (2017) 136e139 D Yoo, D Lee, J Park, J Ahn, S.H Kim, D Lee, Porosity control of nanoporous CuO by polymer confinement effect, Scripta Mater 162 (2019) 58e62 X Miao, S Wang, W Sun, Y Zhu, C Du, R Ma, C Wang, Room-temperature electrochemical deposition of ultrathin CuOx film as hole transport layer for perovskite solar cells, Scripta Mater 165 (2019) 134e139 H Siddiqui, M.S Qureshi, F.Z Haque, Valuation of copper oxide (CuO) nanoflakes for its suitability as an absorbing material in solar cells fabrication, Optik 127 (2016) 3713e3717 J Zhang, J Wang, Y Fu, B Zhang, Z Xie, Sonochemistry-synthesized CuO nanoparticles as an anode interfacial material for efficient and stable polymer solar cells, RSC Adv (2015) 28786e28793 S.P Lonkar, V.V Pillai, S Stephen, A Abdala, V Mittal, Facile in situ fabrication of nanostructured grapheneeCuO hybrid with hydrogen sulfide removal capacity, Nano-Micro Lett (4) (2016) 312e319 H Siddiqui, M.S Qureshi, F.Z Haque, pH-dependent single-step rapid synthesis of CuO nanoparticles and their optical behavior, Optic Spectrosc 123 (6) (2017) 903e912 H Siddiqui, M.R Parra, M.M Malik, F.Z Haque, Structural and optical properties of Li substituted CuO nanoparticles, Opt Quant Electron 50 (2018) 260 H Siddiqui, M.S Qureshi, F.Z Haque, Biosynthesis of flower-shaped CuO nanostructures and their photocatalytic and antibacterial activities, NanoMicro Lett 12 (1) (2020), 29, https://doi.org/10.1007/s40820-019-0357-y S.C Bhise, D.V Awale, M.M Vadiyar, S.K Patil, B.N Kokare, S.S Kolekar, Facile synthesis of CuO nanosheets as electrode for supercapacitor with long cyclic stability in novel methyl imidazole-based ionic liquid electrolyte, J Solid State Electrochem 21 (9) (2017) 2585e2591 H Siddiqui, M.S Qureshi, F.Z Haque, Hexamine (HMT) assisted wet chemically synthesized CuO nanostructures with controlled morphology and adjustable optical behavior, Opt Quant Electron 48 (7) (2016) 349 M.A Dar, S.H Nam, Y.S Kim, W.B Kim, Synthesis, characterization, and electrochemical properties of self-assembled leaf-like CuO nanostructures, J Solid State Electrochem 14 (9) (2010) 1719e1726 H Siddiqui, M.R Parra, F.Z Haque, Optimization of process parameters and its effect on structure and morphology of CuO nanoparticle synthesized via the sol-gel technique, J Sol Gel Sci Technol 87 (1) (2018) 125e135 B Yuan, X Liu, J Liu, M Li, D Wang, Synthesis of different morphologies CuO nanocrystalline under room temperature, Mater Lett 236 (2019) 495e497 M Ikram, M Imran, J.M Nunzi, S Ali, Efficient inverted hybrid solar cells using both CuO and P3HT as an electron donor materials, J Mater Sci Mater Electron 26 (2015) 6478e6483 M Ikram, M Imran, J.M Nunzi, Islah-u-din, S Ali, Replacement of P3HT and PCBM with metal oxides nanoparticles in inverted hybrid organic solar cells, Synth Met 210 (2015) 268e272 E Salim, S.R Bobbara, A Oraby, J.M Nunzi, Copper oxide nanoparticle doped bulk-heterojunction photovoltaic devices, Synth Met 252 (2019) 21e28 A.P Wanninayake, S Gunashekar, S Li, B.C Church, N Abu-Zahra, Performance enhancement of polymer solar cells using copper oxide nanoparticles, Semicond Sci Technol 30 (2015), 064004 L Debbichi, M.C.M Lucas, J.F Pierson, P Krüger, Vibrational properties of CuO and Cu4O3 from first-principles calculations, and Raman and infrared spectroscopy, J Phys Chem C 116 (18) (2012) 10232e10237 H Siddiqui, M Shrivastava, M.R Parra, P Pandey, S Ayaz, M.S Qureshi, The effect of La3ỵ ion doping on the crystallographic, optical and electronic properties of CuO nanorods, Mater Lett 229 (2018) 225e228 H Siddiqui, M.R Parra, P Pandey, M.S Qureshi, F.Z Haque, Combined parametric optimization of P3HT:PC70BM films for efficient bulk-heterojunction solar cells, J Solid State Electrochem 23 (12) (2019) 3267e3274 H Siddiqui, M.R Parra, M.S Qureshi, M.M Malik, F.Z Haque, Studies of structural, optical, and electrical properties associated with defects in sodiumdoped copper oxide (CuO:Na) nanostructures, Mater Sci 53 (12) (2018) 8826e8843 H Siddiqui, M.S Qureshi, F.Z Haque, One step, template free hydrothermal synthesis of CuO tetrapods, Optik 125 (17) (2014) 4663e4667 110 H Siddiqui et al / Journal of Science: Advanced Materials and Devices (2020) 104e110 [32] M.R Parra, P Pandey, H Siddiqui, S.B Qadri, F.Z Haque, New-insight into the physical properties of Zn1-xBxO two dimensional hexagonal nanodisks: an efficient material for dye sensitized solar cells, Mater Lett 238 (2019) 194e197 [33] H Siddiqui, Modification of Physical and Chemical Properties of Titanium Dioxide (TiO2) by Ion Implantation for Dye Sensitized Solar Cells, Ion Beam (2019), https://doi.org/10.5772/intechopen.83566 In press, https://www intechopen.com/online-first/modification-of-physical-and-chemicalproperties-of-titanium-dioxide-tio2-by-ion-implantation-for-dy, 2019 [34] W Cao, J Xue, Recent progress in organic photovoltaics: device architecture and optical design, Energy Environ Sci (2014) 2123e2144 [35] A.D Rao, M.G Murali, A.V Kesavan, P.C Ramamurthy, Experimental investigation of charge transfer, charge extraction, and charge carrier concentration in P3HT:PBD-DT-DPP:PC70BM ternary blend photovoltaics, Sol Energy 174 (2018) 1078e1084 [36] A.P Wanninayake, S Gunashekar, S Li, B.C Church, N Abu-Zahra, CuO nanoparticles based bulk heterojunction solar cells: investigations on morphology and performance, J Sol Energy Eng 137 (3) (2015) 31016 (7 pages) ... is enhanced by the increasing amount of CuO nanoparticles in the active layer (Inset Fig 3b) Further, the performance of the as- prepared CuO nanoparticles in P3HT:PC70BM solar cell was examined... The addition of copper nanoparticles can improve the crystallinity of P3HT [24] The observed increase in crystallinity of the P3HT state seems to be partially accountable for the rise in the absorbance... and infer an obvious increase in surface roughness due to the addition of CuO-NPs The rootmean-square roughness (RMS) value increased from 0.711 nm to 4.188 nm as the addition of CuO-NPs increased