Two-dimensional gallium nitride (2D GaN) has recently received considerable attention due to its excellent physical properties, including high stability, wide and tunable bandgap, and magnetism. 2D GaN offers an accessible way to apply in photocatalytic hydrogen production as composing to vdW heterostructures. Here, we report a first principles study based on the HSE06 functional for the 2D van der Waals (vdW) GaN/InxGa1-xN heterostructures with a tunable bandgap achieved through modulation of indium (In) contents. Such heterostructure is a bilayer vertically stacked by a monolayer of GaN and a monolayer of InxGa1-xN, both of which are graphite-like structures. In particular, the heterostructure bandgap decreases from 3.37 eV to 2.23 eV as In content increases from 0 to 0.5, accompanying by a significant transition from indirect to direct band gap. All of the studied heterostructures have suitable band edge positions for the redox potential of water decomposition at pH 0. Furthermore, increasing In content improves the visible light absorption, carrier mobility and establishes a more effective built-in electric field in the heterostructures. Our results prove that 2D GaN/InxGa1-xN heterostructure is highly suitable as a catalyst for photocatalytic water splitting and provides theoretical guidance for applying 2D GaN in photocatalytic hydrogen production.

中文翻译：

---

In含量对2D GaN/InxGa1-xN异质结构电子和光学性能的影响

二维氮化镓（2D GaN）由于其优异的物理特性，包括高稳定性、宽且可调谐的带隙和磁性，最近受到了广泛的关注。 2D GaN 为构建 vdW 异质结构提供了一种应用于光催化制氢的可行方法。在这里，我们报告了基于 HSE06 泛函的第一性原理研究，该研究适用于 2D 范德华 (vdW) GaN/InxGa1-xN 异质结构，该异质结构具有通过调节铟 (In) 含量实现的可调谐带隙。这种异质结构是由单层GaN和单层InxGa1-xN垂直堆叠的双层，两者都是类石墨结构。特别是，随着In含量从0增加到0.5，异质结构带隙从3.37 eV减小到2.23 eV，伴随着从间接带隙到直接带隙的显着转变。所有研究的异质结构都具有适合 pH 0 时水分解氧化还原电位的能带边缘位置。此外，增加 In 含量可提高可见光吸收、载流子迁移率，并在异质结构中建立更有效的内置电场。我们的研究结果证明2D GaN/InxGa1-xN异质结构非常适合作为光催化水分解催化剂，并为2D GaN在光催化制氢中的应用提供了理论指导。