An Exploration of All-Inorganic Perovskite/Gallium Arsenide Tandem Solar Cells

摘要

All-inorganic perovskite/gallium arsenide (GaAs) tandem solar cells are of greatinterest for potential space applications. Herein, planar all-inorganic fourterminal(4-T) and two-terminal (2-T) perovskite/GaAs tandem solar cells aresimulated and optimized, respectively. To achieve higher absorption in the 4-Tconfiguration, the reflection and parasitic absorption have to be reduced throughoptimizing the thickness of the perovskite and GaAs base, reducing the thicknessof SnO_2 and the organic hole transport layer (HTL), and introducing anantireflection coating, respectively. To balance the short-circuit current andopen-circuit voltage of the GaAs bottom cell, the doping concentration on GaAs isoptimized to 1018 cm~(-3) that has resulted in a high power conversion efficiency(PCE) of 30.97%. Based on the results of 4-T configuration, all-inorganicperovskites with different halide compositions are used for current matching toachieve a high-efficiency 2-T configuration. After studying the effects of defectdensity and optimizing the doping concentration of the GaAs base, an extremelyhigh PCE of 30.67% is achieved based on 2-T CsPbIBr_2/GaAs tandem solar cells.Furthermore, the current mismatching under the AM0 spectrum is eliminated forpotential high altitude/space application, and the device offers a very competitivePCE of 27.23% compared with that of traditional GaAs double-junction tandemsolar cells.