Abstract Designing g-C3N4 based heterojunction photocatalyst by coupling wide-bandgap semiconductors not only promote the increased charge separation but also can provide the opportunity of aptly modulating its thermodynamic properties. Herein, g-C3N4@TiO2-SnO2 nanocomposites has been judiciously designed and is followed to synthesize by a straightforward hydrothermal method. Essentially, g-C3N4 was integrated with TiO2-SnO2 solid solution, composed of two phases (anatase (A) and rutile (R)) to fabricate the g-C3N4@TiO2-SnO2 nanocomposites. The hybrid nanocomposite is utilized as a highly efficient multipurpose photocatalyst for pollutant removal (Methyl orange, Rhodamine B, Cr6+) and H2 evolution under visible/solar light irradiation. The reaction rate constant (k) values forthe pollutant removal using this newly prepared g-C3N4@TiO2-SnO2 nanocomposite is found to be 14.4, 5.6 and 9 times higher than that of TiO2-SnO2, g-C3N4, and the physical mixture, respectively. The H2 evolution rate of g-C3N4@TiO2-SnO2 (220 μmol· h-1·g-1) is also evaluated to be about 10 times higher than that of g-C3N4 (22 μmol· h-1·g-1). The improved photoactivity of g-C3N4@TiO2-SnO2 nanocomposites is attributed to the improved electron-hole separation and the apt modulation of thermodynamic properties.

中文翻译：

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TiO2-SnO2固溶体偶联构建g-C3N4基异质结光催化剂用于高效多用途光催化

摘要 通过耦合宽带隙半导体设计基于 g-C3N4 的异质结光催化剂不仅可以促进电荷分离，而且可以提供适当调节其热力学性质的机会。在此，g-C3N4@TiO2-SnO2 纳米复合材料经过精心设计，并通过直接的水热法合成。本质上，g-C3N4 与 TiO2-SnO2 固溶体结合，由两相（锐钛矿 (A) 和金红石 (R)）组成，以制造 g-C3N4@TiO2-SnO2 纳米复合材料。这种混合纳米复合材料被用作一种高效的多用途光催化剂，用于在可见光/太阳光照射下去除污染物（甲基橙、罗丹明 B、Cr6+）和析氢。发现使用这种新制备的 g-C3N4@TiO2-SnO2 纳米复合材料去除污染物的反应速率常数 (k) 值是 TiO2-SnO2、g-C3N4 和物理混合物的 14.4、5.6 和 9 倍，分别。g-C3N4@TiO2-SnO2 (220 μmol·h-1·g-1) 的析氢速率也被评估为比 g-C3N4 (22 μmol· h-1·g-1) 高约 10 倍）。g-C3N4@TiO2-SnO2纳米复合材料光活性的提高归因于电子-空穴分离的改善和热力学性质的适当调节。