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The hole transporting material (HTM) is responsible for selectively transporting holes and blocking electrons which also plays a crucial role in the efficiency and stability of perovskite solar cells (PSCs). Spiro-MeOTAD is the most popular material, which is expensive and can be easily affected by moisture content. There is a need to find an alternative HTM with sufficiently high resistance to moisture content. In this paper, the influence of some parameters with cuprous oxide (Cu2O) as HTM was investigated using a solar cell capacitance simulator (SCAPS). These include the influence of doping concentration and thickness of the absorber layer, the effect of thickness of ETM and HTM as well as electron affinities of ETM and HTM on the performance of the PSCs. From the obtained results, it was found that the concentration of dopant in the absorber layer, the thickness of ETM and HTM and the electron affinity of HTM and ETM affect the performance of the solar cell. The cell performance improves greatly with the reduction of ETM electron affinity and its thickness. Upon optimization of parameters, power conversion efficiency for this device was found to be 20.42% with a current density of 22.26 mAcm-2, voltage of 1.12 V, and fill factor of 82.20%. The optimized device demonstrates an enhancement of 58.80%, 2.25%, 20.40% and 30.23% in PCE, Jsc, FF, and Voc over the initial cell. The results show that Cu2O in lead-based PSC as HTM is an efficient system and an alternative to spiro-MeOTAD.

Abstract:The enhancement in efficiency of dye sensitized solar cells decorated with size-controlled silver nanoparticles based on anthocyanins as light harvesting pigment through successive ionic layer adsorption and reaction (SILAR) was demonstrated. Studies indicate that, the short-circuit current density (J SC ) and open-circuit voltage (V OC ), of DSSCs containing AgNPs were significantly improved. The photovoltaic (PV) performance decreased with increasing size of AgNPs from one SILAR cycle to two SILAR cycles, the best performance was achieved using the anode prepared with one SILAR cycle. An enhancement of 35.8 % was achieved when the thickness was around 16 nm (one SILAR) over the bare FTO device. When the size of AgNPs was around 32 nm (two SILAR), an enhancement of 10.4% was recorded over the reference device. This selective enhancement in efficiency in the Ag plasmonic absorption regions is indicative of the fact that the incorporation of metal nanoparticles is beneficial for enhanced absorption and charge separation.

This research paper is on Density Functional Theory (DFT) within Local Density Approximation. The calculation was performed using Fritz Haber Institute Ab-initio Molecular Simulations (FHI-AIMS) code based on numerical atomic-centered orbital basis sets. The electronic band structure, total density of state (DOS) and band gap energy were calculated for Gallium-Arsenide and Aluminium-Arsenide in diamond structures. The result of minimum total energy and computational time obtained from the experimental lattice constant 5.63 A for both Gallium Arsenide and Aluminium Arsenide is −114,915.7903 eV and 64.989 s, respectively. The electronic band structure analysis shows that Aluminium-Arsenide is an indirect band gap semiconductor while Gallium-Arsenide is a direct band gap semiconductor. The energy gap results obtained for GaAs is 0.37 eV and AlAs is 1.42 eV. The band gap in GaAs observed is very small when compared to AlAs. This indicates that GaAs can exhibit high transport property of the electron in the semiconductor which makes it suitable for optoelectronics devices while the wider band gap of AlAs indicates their potentials can be used in high temperature and strong electric fields device applications. The results reveal a good agreement within reasonable acceptable errors when compared with the theoretical and experimental values obtained in the work of Federico and Yin wang [1] [2].

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