Multifunctional Optimization of MXene for Enhanced Comprehensive Performance of Crystal Silicon‐MXene Back‐Heterojunction Solar Cells

Abstract

Enhancing the cost‐performance ratio is a fundamental objective for the advancement of the photovoltaic sector. In this context, the development of innovative solar cells that offer a straightforward device configuration but high performance is arguably the most crucial element. Herein, an undoped back‐heterojunction crystalline silicon (c‐Si) solar cell is endeavored to be crafted by simply drop‐casting a Ti3C2Tx MXene ethanol colloidal solution onto the backside of an n‐type c‐Si (n‐Si) wafer. Leveraging the good electrical property and stability, as well as the adjustable work function of MXene treated by europium trifluoromethanesulfonate (Eu(OTF)3), the elementary Ag/ZnO/n‐Si/MXene/Ag solar cell delivers an impressive power conversion efficiency (PCE) of 12.5%. Moreover, the deposition of a SiO2 passivation layer through a simple self‐developed electrochemical method increases the PCE further to 13.5% by ameliorating the interfacial contact between MXene and n‐Si. Moreover, this unencapsulated solar cell exhibits improved stability, compared to the control device without Eu(OTF)3 treatment and SiO2 passivation.