FeNi层状双氢氧化物/TiO2复合光催化剂的制备及其制氢性能

层状双氢氧化物(LDH)的光生电子-空穴对易复合,虽然纳米薄片的结构促进了载流子分离,但其光催化效率仍然较低。我们利用LDH薄片结构的优势,将FeNi LDH和TiO₂通过静电自组装复合,设计制备出新型高效的FeNi LDH/TiO₂复合光催化材料,评价了其光催化分解水产氢性能。对其结构、光催化性能和光电化学等进行了详细表征。结果表明,FeNi LDH的高比表面积、复合物的异质结结构都有利于光生电荷的转移。光催化产氢结果表明,FeNi LDH/TiO₂复合材料的产氢速率(22.6mmol·g^-1·h^-1)分别比纯TiO₂(0.1 mmol·g^-1·h^-1)和FeNi LDH(0.05 mmol·g^-1·h^-1)提高了226和452倍,表明了异质结在提高LDH光催化效率方面的重要作用。

FeNi Layered Double Hydroxide/TiO2 Composite Photocatalyst: Preparation and Hydrogen Production Performance

Layered double hydroxide (LDH) photogenerated electron-hole pairs are easy to recombine. Although the unique structure of nanosheets promotes the separation of carriers, the photocatalytic efficiency is still low. In this paper, taking advantage of its thin-film structure, FeNi LDH was combined with TiO₂ by electrostatic self-assembly method to design and prepare efficient FeNi LDH/TiO₂ composite photocatalysts, and evaluated its hydrogen production performance. Their structure, photocatalytic performance and photoelectrochemistry were characterized in detail. The results showed that the high specific surface area of FeNi LDH and the heterojunction structure of the composite were all conducive to photo-generated charge transfer. The results of photocatalytic hydrogen production showed that the hydrogen production rate (22.6 mmol·g^-1·h^-1) of FeNi LDH/TiO₂ composite was 226 and 452 times higher than that of bare TiO₂ (0.1 mmol·g^-1·h^-1) and FeNi LDH (0.05 mmol·g^-1·h^-1) respectively, indicating the crucial role of heterojunction in improving the photocatalytic efficiency of LDH.