Shang Qianqian, Fang Yuzhen, Yin Xingliang, Kong Xiangjin
College of Chemistry and Chemical Engineering, Liaocheng University Liaocheng 252000 China
RSC Adv. 2021 Nov 18;11(59):37089-37102. doi: 10.1039/d1ra07691d. eCollection 2021 Nov 17.
Structure design of photocatalysts is highly desirable for taking full advantage of their abilities for H evolution. Herein, the highly-efficient TiO{001}/g-CN (TCN) heterostructures have been fabricated successfully an ethanol-thermal method. And the structure of g-CN in the TCN heterostructures could be exfoliated from bulk g-CN to nanosheets, nanocrystals and quantum dots with the increase of the synthetic temperature. Through detailed characterization, the structural evolution of g-CN could be attributed to the enhanced temperature of the ethanol-thermal treatment with the shear effects of HF acid. As expected, the optimal TCN-2 heterostructure shows excellent photocatalytic H evolution efficiency (1.78 mmol h g) under visible-light irradiation. Except for the formed built-in electric field, the significantly enhanced photocatalytic activity of TCN-2 could be ascribed to the enhanced crystallinity of TiO{001} nanosheets and the formed g-CN nanocrystals with large surface area, which could extend the visible light absorption, and expedite the transfer of photo-generated charge carriers further. Our work could provide guidance on designing TCN heterostructures with the desired structure for highly-efficient photocatalytic water splitting.
为了充分利用光催化剂的析氢能力，对其进行结构设计是非常必要的。在此，通过乙醇热法成功制备了高效的TiO{001}/g-CN（TCN）异质结构。随着合成温度的升高，TCN异质结构中g-CN的结构可以从块状g-CN剥离成纳米片、纳米晶体和量子点。通过详细表征，g-CN的结构演变可归因于乙醇热处理温度的升高以及HF酸的剪切作用。正如预期的那样，最佳的TCN-2异质结构在可见光照射下表现出优异的光催化析氢效率（1.78 mmol h g）。除了形成的内建电场外，TCN-2显著增强的光催化活性可归因于TiO{001}纳米片结晶度的提高以及具有大表面积的g-CN纳米晶体的形成，这可以扩展可见光吸收，并进一步加速光生载流子的转移。我们的工作可为设计具有所需结构的TCN异质结构以实现高效光催化水分解提供指导。
