Compositional Engineering of Perovskite Absorber Material to Enhance the Stability of PSCs /

Abstract

The development of organometal halide-based perovskites solar cells (PSCs) has made remarkable progress in the photovoltaic technology field. The commercialization of PSCs is being rendered owing to its poor stability and higher material cost for hole transport layer (HTL) and electrodes. To counter these issues carbon-based HTL and noble-metal-free PSCs are being used. In this work, we systematically studied the effect of Cs-doping on perovskite film morphology and device performance. The results showed that when Cs-doping concentration was in the range of 9%, there was a substantial change in the optoelectronic and morphological properties of perovskite film. The grain size was improved from 70nm (undoped film) to 170nm (9% Cs-doped film) with a reduction in the grain boundaries. The device fabrication was carried out in a dry glove box at 10% relative humidity by using carbon as a counter electrode (CE). Consequently, Cs-doping with carbon CE improved the hydrophobicity and non-radiative charge recombination at the surface of the carbon/perovskite film interface. The efficiency of the devices was improved to 5.27% at a 9% Cs-doping level as compared to the 0% Cs-doping with 1.55% efficiency. Moreover, this technique will reduce the fabrication costs of PSCs significantly promising a sustainable future for this technology.