Analyzing the hetero-junction compatibility of Al2CdX4 chalcogenides as charge transport layers with lead-free perovskite layer

Recently, ternary Al2CdX4 (X = S, Se, Te) chalcogenides have emerged as excellent active layers in thin film photovoltaic cells due to their excellent light harvesting properties. These materials have high conductivity and are p-type doped making them a viable option to be used as hole transport layers (HTLs) in perovskite solar cells (PSCs). In this study the hetero-junction compatibility of chalcogenides with the lead-free MAGeI(3) perovskite were investigated in detail. Three different PSC cells were modelled in SCAPS-1D. Analysis of energy band alignment, band offsets, electric potential, JV, current profile, recombination, absorption and quantum efficiency were carried out to find their suitability. After that the optimization of perovskite thickness, HTL doping, reflection layer concentration and anode work function were carried out to unlock the full potential of the PSCs, which improved the PCE by more than 6%. Finally, the stability analysis of the PSCs for interface defects and temperature was done. The study found that the least compatible material was Al2CdS4 due to its large valance band offset of 0.89 eV, producing a PCE of 0.05%. While the most compatible was Al2CdSe4, which produced the highest performance with PCE of 25.93%, Jsc of 17.02 mA/cm(2), Voc of 1.75 V and FF of 87.25%.