Polymer Solar Cells (PSCs) are one of the most promising alternatives to the more expensive silicon solar cells. It has many advantages, such as being very cheap to produce, high transparency in the visible range, high mechanical flexibility and excellent thermal stability. However, their power conversion efficiencies are still low (conceived as mainly caused by electron hole recombination process) compared with conventional silicon photovoltaic cells. In an attempt to design a photo anode with an increased work function and conductivity for an efficient transport pathway from the photo injected charge carriers to the current collectors which enhances the performance of a polymer solar cell, this study modified the polyaniline (PANI; as photoactive anode) by incorporating it with green synthesized copper nanoparticles.The copper nanoparticle (CuNPs) were biologically synthesized from fresh Siam leaf (Chromolenae odorata) and characterized using spectroscopic techniques such as SEM, FTIR, XRD, AFM and UVs. The modified photoactive film layer that was used as anode was fabricated by incorporating the synthesized CuNPs with PANI using spin coating techniques to deposit the composite of the polymer on to the surface of conducting glasses. Optimization of the processing parameters of the modified active anode layer of the polymer solar cells were analyzed by considering the mixing ratio of the synthesized NPs and PANI, thickness of the film layer through RPM, annealing temperature and annealing time. The optical and electrical analyses of the modified active layer were studied using four point probes. The current –voltage characteristics of the assembled polymer solar cells based on modified active layer was then analyzed using solar simulator.The result of SEM, FTIR and AFM showed that copper nanoparticles was prepared successfully, the XRD spectral analysis showed the diffraction peaks of (111), (200), (220) plane while the UV-visible spectroscopy revealed an intensive absorption in the ultraviolet band of about 200 to 400 nm with the highest absorbance of 1.08% at the optical spin coating of 2000RPM and annealing temperature of 400 at annealing time of 30 min. At increasing annealing temperature, there is increased photon energy absorption while at increasing wavelength, absorption decreases. The electrical properties revealed the short circuit current (ISC = 1.675mA/cm2), open circuit voltage (VOC = 26.30V), fill factor (FF = 50.7), percentage efficient conversion (PCE = 12.08%), resistivity ( ρ = 0.135?m), sheet resistance(R = 0.248?) and conductivity( σ = 7.41 S/m) for copper/polymer based photoactive anode were recorded.It can be concluded that, optimized spin coating speed of different mixing ratio and annealing condition leads to an increase in optical properties of the devices. However, copper/polymer-based photoactive anode layer gives high performance in the enhancement of solar cell devices when compared to pure polymer and copper nanoparticles. Based on this, the modified active layer can be applied to design polymer solar cells and to improve the efficiency of polymer solar cells.
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