Facile method for fabricating the MXenes-Si based Schottky-junction solar cells

Owing to their tunable properties, 2D materials including MXenes are widely used in different optoelectronic devices due to their inherent conductivity and transparency. MXenes are a class of 2D materials that can be synthesized in the form of a colloidal solution, and these are hydrophilic in nature. Due to their hydrophilicity, MXenes can be easily coated on different substrates, making them suitable in applications like solar cells. Like other materials, MXenes-based solar cell fabrication doesn't require a growth process or a transfer process, hence, solar cells fabrication using MXenes is comparatively a simplified process. In this study, a facile technique was adopted to fabricate the metal-semiconductor (MXenes-Si) junction simply by spin-coating Ti(3)C(2)Tx-MXenes on an n-type Si substrate. The electrical properties of the coated MXenes films were investigated at different MXenes to DI water ratios to obtain the optimized concentration for the highest solar cell efficiency. To stabilize the interface between MXenes and Si, Al2O3 was deposited, and the thickness-dependent tunneling effect was also optimized at a 2 nm thick Al2O3 layer. To improve the solar cell efficiency, AuCl3 doping, and texturing of silicon substrate were performed. With these two additional treatments, the efficiency of the solar cell was increased from 2.87% to 3.36%, exhibiting an increase of similar to 17% as compared to that without treatment.