Large Area and High‐Efficiency MXene–Silicon Solar Cells by Organic Enhanced Dispersity and Work Function

Abstract

2D transition metal carbon/nitrides (MXenes) have lately attracted increased attention in photovoltaic (PV) because of their good optical and electrical properties. MXenes–silicon solar cells as a novel PV device are considered to be a low‐cost strategy for boosting Si‐based device development. Nevertheless, power conversion efficiency (PCE) and large area preparation are limited in their future applications. Here, the solubilization of Ti2CTx (T = O, F, OH) MXene multilayer nanosheets is reported and thus the ability of scaled coating of Ti2CTx MXene thin films using an organic Nafion polymer solution is enhanced. It is demonstrated that an effect of termination by Nafion to Ti2CTx MXene groups (MXene:Nafion) dramatically enhanced the work function of the Ti2CTx MXene from 3.96 to 5.17 eV. Due to the excellent passivation ability of the organic Nafion species, the MXene:Nafion increases the effective carrier lifetime of silicon wafers to 2.52 ms compared with unpassivated control (0.03 ms). These results finally contribute to the high PCE of 14.21% of MXene:Nafion–Si solar cell with a large area of 7.29 cm2. This work proposes a large area MXene:Nafion–Si heterojunction solar cell with high performance and low cost, which points to the great promise of such a device for future application.