当前位置：
X-MOL 学术
›
Phys. Chem. Chem. Phys.
›
论文详情
Our official English website, www.x-mol.net, welcomes your
feedback! (Note: you will need to create a separate account there.)
Thickness-induced band-gap engineering in lead-free double perovskite Cs2AgBiBr6 for highly efficient photocatalysis
Physical Chemistry Chemical Physics ( IF 2.9 ) Pub Date : 2021-4-24 , DOI: 10.1039/d0cp03919e Bing-Hao Wang 1, 2, 3, 4, 5 , Bin Gao 1, 2, 3, 4, 5 , Jin-Rong Zhang 1, 2, 3, 4, 5 , Lang Chen 1, 2, 3, 4, 5 , Guo Junkang 1, 2, 3, 4, 5 , Sheng Shen 1, 2, 3, 4, 5 , Chak-Tong Au 2, 5, 6, 7 , Kenli Li 3, 4, 5, 8 , Meng-Qiu Cai 3, 4, 5, 9 , Shuang-Feng Yin 1, 2, 3, 4, 5
Physical Chemistry Chemical Physics ( IF 2.9 ) Pub Date : 2021-4-24 , DOI: 10.1039/d0cp03919e Bing-Hao Wang 1, 2, 3, 4, 5 , Bin Gao 1, 2, 3, 4, 5 , Jin-Rong Zhang 1, 2, 3, 4, 5 , Lang Chen 1, 2, 3, 4, 5 , Guo Junkang 1, 2, 3, 4, 5 , Sheng Shen 1, 2, 3, 4, 5 , Chak-Tong Au 2, 5, 6, 7 , Kenli Li 3, 4, 5, 8 , Meng-Qiu Cai 3, 4, 5, 9 , Shuang-Feng Yin 1, 2, 3, 4, 5
Affiliation
|
In recent years, two-dimensional (2D) lead-free double perovskites have been attracting much attention because of their unique performance in photovoltaic solar cells and photocatalysis. Nonetheless, how thickness affects the photoelectric properties of lead-free double perovskite remains unclear. In this work, by means of density functional theory (DFT) with a spin orbit coupling (SOC) effect, we have investigated the electronic and optical properties systemically, including band structures, carrier mobility, optical absorption spectra, exciton-binding energies, band edges alignment and molecule adsorption performance of Cs2AgBiBr6 with different thicknesses. The calculated results revealed the thickness-induced band gap and optical performance for Cs2AgBiBr6. It shows a low band gap and outstanding optical absorption of visible and ultraviolet light. When the thickness is reduced to a monolayer, Cs2AgBiBr6 moves from an indirect band gap to a direct band gap. Moreover, the carrier mobility of Cs2AgBiBr6 is excellent and the exciton-binding energy increases with the decreased thickness. Importantly, an analysis of molecule adsorption and band edge alignment indicates that Cs2AgBiBr6 is prone to H2O adsorption and H2 desorption theoretically, which is conducive to the photocatalytic water splitting for hydrogen generation and other photovatalytic reactions. Our work suggests that Cs2AgBiBr6 is a potential candidate as a solar cell or a photocatalyst, and we provide theoretical explorations into reducing the layers of lead-free double perovskite materials to 2D atomic thickness for a better photocatalytic application, which can serve as guidelines for the design of excellent photocatalysts.
中文翻译：
无铅双钙钛矿Cs2AgBiBr6中厚度诱导的带隙工程用于高效光催化
近年来，二维（2D）无铅双钙钛矿因其在光伏太阳能电池和光催化方面的独特性能而备受关注。然而，厚度如何影响无铅双钙钛矿的光电性能仍不清楚。在这项工作中，借助具有自旋轨道耦合（SOC）效应的密度泛函理论（DFT），我们系统地研究了电子和光学性质，包括能带结构，载流子迁移率，光吸收谱，激子结合能，能带厚度的Cs 2 AgBiBr 6的边缘排列和分子吸附性能。计算结果表明，厚度诱导带隙和Cs 2 AgBiBr的光学性能6。它显示出低的带隙以及对可见光和紫外光的出色光学吸收。当厚度减小到单层时，Cs 2 AgBiBr 6从间接带隙移动到直接带隙。此外，Cs 2 AgBiBr 6的载流子迁移率极好，并且激子结合能随厚度的减小而增加。重要的是，对分子吸附和能带边缘排列的分析表明，Cs 2 AgBiBr 6易于吸附H 2 O和H 2。从理论上讲解吸，这有利于光催化水分解产生氢和其他光催化反应。我们的工作表明，Cs 2 AgBiBr 6可以作为太阳能电池或光催化剂的潜在候选者，并且我们提供了将无铅双钙钛矿材料的层减少到2D原子厚度以进行更好的光催化应用的理论探索，这可以用作优秀光催化剂设计指南。
更新日期：2021-05-25
中文翻译：
无铅双钙钛矿Cs2AgBiBr6中厚度诱导的带隙工程用于高效光催化
近年来，二维（2D）无铅双钙钛矿因其在光伏太阳能电池和光催化方面的独特性能而备受关注。然而，厚度如何影响无铅双钙钛矿的光电性能仍不清楚。在这项工作中，借助具有自旋轨道耦合（SOC）效应的密度泛函理论（DFT），我们系统地研究了电子和光学性质，包括能带结构，载流子迁移率，光吸收谱，激子结合能，能带厚度的Cs 2 AgBiBr 6的边缘排列和分子吸附性能。计算结果表明，厚度诱导带隙和Cs 2 AgBiBr的光学性能6。它显示出低的带隙以及对可见光和紫外光的出色光学吸收。当厚度减小到单层时，Cs 2 AgBiBr 6从间接带隙移动到直接带隙。此外，Cs 2 AgBiBr 6的载流子迁移率极好，并且激子结合能随厚度的减小而增加。重要的是，对分子吸附和能带边缘排列的分析表明，Cs 2 AgBiBr 6易于吸附H 2 O和H 2。从理论上讲解吸，这有利于光催化水分解产生氢和其他光催化反应。我们的工作表明，Cs 2 AgBiBr 6可以作为太阳能电池或光催化剂的潜在候选者，并且我们提供了将无铅双钙钛矿材料的层减少到2D原子厚度以进行更好的光催化应用的理论探索，这可以用作优秀光催化剂设计指南。
京公网安备 11010802027423号