Two-Dimensional Perovskite/HfS2 van der Waals Heterostructure as an Absorber Material for Photovoltaic Applications

Deobrat Singh,Rajeev Ahuja

doi:10.1021/acsaem.1c03796

Abstract

Van der Waals (vdW) heterostructures of perovskites and transition metal dichalcogenides (TMDCs) have attracted increased interest owing to their extraordinary optoelectronic properties and encouraging applications. Two-dimensional (2D) TMDCs, i.e., hafnium disulfide (HfS2), are also interesting because of their unique optoelectronic properties. Therefore, the combination of these different types of materials is very smart in terms of the fundamental science of interface interaction, as well as for the understanding of ultrathin optoelectronic devices with superior performance. Here, we have systematically modeled the 2D CH3NH3PbI3/HfS2 vdW heterostructure by using first-principles calculations. The substituted interface has enhanced visible-light sensitivity and photoelectrocatalytic activity by reducing the transition energies. The interfacial interaction of both materials effectively tunes the band gap of the interface; therefore, it would significantly improve the photoreactivity for solar cell applications. Due to the presence of small effective masses of electrons–holes, high optical absorption on the order of 105 and high spectroscopic limited maximum efficiency of 28.45% in the CH3NH3PbI3/HfS2 vdW heterostructure will be better candidates in the field of absorber materials. The considered systems are expected to be more efficient in separating the photogenerated electrons–holes and active in the visible spectrum. These theoretical results suggest that the CH3NH3PbI3/HfS2 vdW heterostructure may lead to many novel applications in efficient light-absorbing materials for photovoltaic applications.

Highlights

Hybrid organic−inorganic lead halide perovskites have greatly attracted interest toward photovoltaic absorber materials due to their remarkable optoelectronic properties such as high optical absorption spectra in the visible region, tunable band gap, and long electron−hole diffusion lengths.[1−3] These interesting properties are very useful in solar cells, and it is reported that the power conversion efficiency has been significantly enhanced in the lead halide perovskites-based solar cells in the past few years along with their values of 22.7%
We mainly focused on the structural, electronic, and optical properties and charge transfer mechanism at the interface of a CH3NH3PbI3/HfS2 Van der Waals (vdW) heterostructure using first-principles calculations based on Density Functional Theory (DFT)
We have systematically investigated structural, electronic, and optical properties of the CH3NH3PbI3/HfS2 vdW heterostructure using first-principles calculations

Summary

Introduction

Hybrid organic−inorganic lead halide perovskites have greatly attracted interest toward photovoltaic absorber materials due to their remarkable optoelectronic properties such as high optical absorption spectra in the visible region, tunable band gap, and long electron−hole diffusion lengths.[1−3] These interesting properties are very useful in solar cells, and it is reported that the power conversion efficiency has been significantly enhanced in the lead halide perovskites-based solar cells in the past few years along with their values of 22.7%. 1.29 eV,[20] and it shows other promising properties such as ultrahigh room temperature carrier mobility, chemical stability, mechanical flexibility, sheet current density, and reasonable band gap.[19,21] Due to these exciting properties of the 1T-HfS2 monolayer, it is a very useful application in the fields of photocatalyst, field-effect transistors, photodetectors, phototransistor, and thermoelectric.[19,22,23] A tunable electronic band gap can be controlled by increasing/decreasing the thickness of 2D CH3NH3PbI3 perovskites.[10,14] the preparation of the heterostructure of 2D perovskites with the other 2D layered materials is expected to provide a new exciting phenomenon and to explore the physical/chemical properties of the individual constituents. 2D monolayers of semiconducting transition metal dichalcogenides (TMDCs) are the best favorable candidates for optoelectronic properties, for example, molybdedniusmulfiddiesu(lfiHdfeS2()M.15o−S127), tungsten Some of disulfide (WS2), and hafnium the TMDC monolayers have direct band gaps in the visible region such as MoS2, WS2, MoSe2, WSe2, MoTe2, etc.; whereas the TMDC HfS2 monolayer displayed the indirect band gap, and it contains a three atom thick layered 2D structure.[18,19] The TMDC 2D 1T-HfS2 monolayer shows exciting electronic and optical properties.[19]

Methods

Results

Conclusion