花球状Ti3C2/TiO2复合材料的制备及其光催化性能

Preparation and photocatalytic properties of flower like Ti3C2/TiO2 composites

摘要:

利用二维（2D）层状Ti3C2衍生出三维（3D）花球状Ti3C2/TiO2复合光催化剂。通过XRD、SEM、TEM、UV-Vis DRS和PL等分析手段对材料进行表征，并比较不同温度下合成的Ti3C2/TiO2的光催化活性。结果表明，500 ℃下合成的Ti3C2/TiO2对酸性品红（AF）表现出更好的光催化降解效率，光反应90 min，降解率达到97.57%。Ti3C2凭借其高导电性以及与TiO2界面形成的肖特基势垒，有效地提高了电荷分离率，抑制了电子-空穴的复合，从而提高了材料的光催化活性。此外，光催化剂稳定性较好，重复循环使用5次后，AF降解率仍能达到86.39%。活性物种捕获实验表明，空穴（h+）和超氧自由基（·O2-）是降解AF的主要活性物质。本研究揭示了Ti3C2对光催化性能提高的增强机制，并为MXene材料在光催化领域中的应用提供了相关参考。

Abstract:

Three dimensional (3D) flower ball Ti3C2/TiO2 composite photocatalyst was derived from two-dimensional (2D) layered Ti3C2. The materials were characterized by XRD, SEM, TEM, UV-Vis DRS and PL analytical methods, and the photocatalytic activity of Ti3C2/TiO2 synthesized at different temperatures was compared. The results showed that Ti3C2/TiO2 synthesized at 500 ℃ showed better photocatalytic degradation efficiency for acid fuchsin (AF). After 90 min of light reaction, the degradation rate reached 97.57%. With its high conductivity and Schottky barrier formed at the interface with TiO2, Ti3C2 effectively improves the charge separation rate, inhibits the electron hole recombination, and improves the photocatalytic activity of the material. In addition, the photocatalyst has good stability. After repeated cycles of use for 5 times, the AF degradation rate can still reach 86.39%. Active species capture experiments show that holes (h+) and superoxide radicals (·O2-) are the main active substances that degrade AF. This study reveals the enhancement mechanism of Ti3C2 to the improvement of photocatalytic performance, and provides a relevant reference for the application of MXene materials in the field of photocatalysis.