High-Throughput Computational Screening and Machine Learning Modeling of Janus 2D III–VI van der Waals Heterostructures for Solar Energy Applications

Abstract

Two-dimensional Janus III−VI monolayers and corresponding van der Waals (vdW) heterostructures present immense application potential in the solar energy conversion areas. In this work, we present material screening and machine learning modeling to accelerate the discovery of promising photocatalytic and photovoltaic candidates in Janus III−VI vdW heterostructures. A comprehensive database with a total of 19926 heterostructures has been proposed according to the high-throughput firstprinciples calculations. It is highlighted that we develop an accurate machine learning model using only atoms and bonds as descriptors based on the crystal graph convolutional neural network framework. Besides, 1035 Janus III−VI vdW heterostructures have been screened out according to the essential criteria of stability. Moreover, we find 66 and 71 potential candidates for photocatalysis and solar cells, respectively, from further application-driven screening. Interestingly, the screened type-II SeInAlS/ SeGaAlTe heterostructure with a band gap of 1.18 eV is highlighted as an internal electric field-driven asymmetrical photocatalyst. On the other hand, the type-II Al 2 STe/Al 2 SSe heterostructure solar cell presents power conversion efficiencies higher than 21% both from the microscopic and mesoscopic point of views. We believe that our study will provide a feasible strategy for the design of III− VI monolayers for solar energy applications.

Theoretical design of two-dimensional AMInP2X3Y3 (AM = Li, Na, K; X/Y = S, Se, Te) monolayers for highly efficient excitonic solar cells

“…Since the first solar cells were developed in the 1950s, 1 the search has continued for solar cell materials with higher power conversion efficiencies (PCEs). [2][3][4][5][6][7][8][9][10] Solar cells can be divided into two categories according to their photoelectric conversion mechanism, namely, conventional solar cells 3,4 and excitonic solar cells (XSCs). 5,[11][12][13][14][15] Conventional solar cells are pn-junction cells fabricated from bulk inorganic semiconductors such as Si, GaAs, and CdTe, 2 which suffer from non-radiative recombination of photogenerated electron-hole pairs, severely limiting their solar energy conversion efficiency.…”

“…17,18 Experimentally, however, most of the heterojunction solar cells still exhibit efficiencies of less than 12%. [19][20][21] It has been theoretically found that the maximum PCEs of 2D heterojunction solar cells consisting of heterobilayers lie in the range of 10-20%, 5,6,[8][9][10][22][23][24][25][26] with only a few of 2D heterojunction solar cells (e.g., a-AsP/GaN, In 2 STe/Al 2 SSe, GaAs/InAs, HfSe 2 /GeO 2 , TiNF/TiNCl, h-BAs/h-BP, boron pnictide/MoSSe, b-PdTe 2 /MoSe 2 , and b-PdTe 2 /MoTe 2 ) being capable of achieving large PCEs over 20%. [5][6][7][8][9][10]27,28 However, most of the compositing 2D materials have not been experimentally realized.…”

“…, α-AsP/GaN, In 2 STe/Al 2 SSe, GaAs/InAs, HfSe 2 /GeO 2 , TiNF/TiNCl, h-BAs/h-BP, boron pnictide/MoSSe, β-PdTe 2 /MoSe 2 , and β-PdTe 2 /MoTe 2 ) being capable of achieving large PCEs over 20%. 5–10,27,28 However, most of the compositing 2D materials have not been experimentally realized. Thus, these 2D heterojunction solar cells cannot be constructed and their performance cannot be measured.…”

“…[19][20][21] It has been theoretically found that the maximum PCEs of 2D heterojunction solar cells consisting of heterobilayers lie in the range of 10-20%, 5,6,[8][9][10][22][23][24][25][26] with only a few of 2D heterojunction solar cells (e.g., a-AsP/GaN, In 2 STe/Al 2 SSe, GaAs/InAs, HfSe 2 /GeO 2 , TiNF/TiNCl, h-BAs/h-BP, boron pnictide/MoSSe, b-PdTe 2 /MoSe 2 , and b-PdTe 2 /MoTe 2 ) being capable of achieving large PCEs over 20%. [5][6][7][8][9][10]27,28 However, most of the compositing 2D materials have not been experimentally realized. Thus, these 2D heterojunction solar cells cannot be constructed and their performance cannot be measured.…”

Tunability of the electronic properties and contact types of the silicane/MoSi2N4heterostructure under an electric field

“…Moreover, this value of band gap for the SiH/MoSi 2 N 4 heterostructure is a suitable band gap with the best light absorption characteristics. 54 The partial density of states (PDOS) of all atoms in the SiH/MoSi 2 N 4 heterostructure are also plotted in Fig. 2(d).…”