High-performance 2D/3D hybrid dimensional p–n heterojunction solar cell with reduced recombination rate by an interfacial layer

Abstract

Two-dimensional transition metal dichalcogenides (2D-TMDs)-based energy conversion devices have received much consideration because of their unique and novel characteristics. In this research, 2D-TMD molybdenum disulfide (MoS₂) and hexagonal boron nitride (h-BN) were grown on a 3D silicon (p-Si) substrate to design a MoS₂/interfacial layer/Si hybrid dimensional p–n heterojunction solar cell. The estimated values of Schottky barrier height (SBH) were 0.72 to 0.91 eV in the case of SiO₂, Al₂O₃, and h-BN as interfacial layers, respectively. The ideality factor was amended from 1.97 to 1.20 with h-BN as an interfacial layer because of the improvement in interface quality and reduction in recombination rate. The recombination resistance was calculated using the diode ideality factor, which was more significant than that of pristine devices. Further, the recombination rate and charge transfer of charge carriers were explained by using the diode model and Simmons-based approximation of tunneling (direct tunneling (DT) and Fowler–Nordheim tunneling (FNT)). A high open circuit voltage (Voc) value of 0.61 V was obtained with h-BN. The hybrid dimensional p–n heterojunction solar cell showed the efficiency of 7.2, 9.1, and 11.8% with SiO₂, Al₂O₃, and h-BN as interfacial layers, respectively, which was much higher as compared to the reference sample (n-MoS₂/p-Si) and previously reported values. These findings provide a unique platform for developing high-performance and astonishing optoelectronics devices.