Two-dimensional heterojunctions with higher carrier mobility and larger specific surface area exhibit numerous applications in photovoltaics and energy. In this work, the MoSi₂N₄/AlN heterojunction structure was established, and the first-principles calculations were performed on its electronic properties, photocatalytic properties and power conversion efficiency, oxygen and hydrogen evolution reaction, electronic and photovoltaic characteristics under electric fields and strains, along with the photogalvanic effect. The results reveal that the MoSi₂N₄/AlN heterojunction displays an indirect bandgap semiconductor with a bandgap of 1.91 eV, generating an intrinsic electric field at the interface from AlN to MoSi₂N₄. It conforms to the S-scheme carrier transfer mechanism and can completely cross the oxidation and reduction potentials of water at pH values of 0-14. The power conversion efficiency can reach up to 15.21%. Hydrogen precipitation reaction occurs at the AlN side, while oxygen precipitation reaction generates at the MoSi₂N₄ side. At the photon energy of 2.5 eV, the maximum current can be achieved for the MoSi₂N₄/AlN heterojunction. This research can provide a novel strategy for the design and manufacture of optoelectronic devices with better performance.

中文翻译：

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具有 2D 异质结的 S 型 MoSi2N4/AlN，用于光催化水解离


具有更高载流子迁移率和更大比表面积的二维异质结在光伏和能源领域表现出许多应用。本工作建立了 MoSi ₂ N ₄ /AlN 异质结结构，并对其电子性质、光催化性能和功率转换效率、析氧析氢反应、电场和应变下的电子和光伏特性以及光电流效应进行了第一性原理计算。结果表明，MoSi ₂ N ₄ /AlN 异质结显示出带隙为 1.91 eV 的间接带隙半导体，在 AlN 到 MoSi ₂ N ₄ 的界面处产生本征电场。它符合 S 型载流子转移机制，在 pH 值为 0-14 时可以完全跨越水的氧化和还原电位。功率转换效率可达 15.21%。氢沉淀反应发生在 AlN 侧，而氧沉淀反应发生在 MoSi ₂ N ₄ 侧。在 2.5 eV 的光子能量下，MoSi ₂ N ₄ /AlN 异质结可以达到最大电流。这项研究可以为设计和制造性能更好的光电器件提供一种新的策略。