Gan Wei, Fu Xucheng, Jin Juncheng, Guo Jun, Zhang Miao, Chen Ruixin, Ding Chunsheng, Lu Yuqing, Li Jianrou, Sun Zhaoqi
School of Materials Science and Engineering, Anhui University, Hefei 230601, Anhui Province, PR China.
College of Materials and Chemical Engineering, West Anhui University, LuAn 237015, Anhui Province, PR China.
J Colloid Interface Sci. 2024 Jan;653(Pt B):1028-1039. doi: 10.1016/j.jcis.2023.09.136. Epub 2023 Sep 25.
Developing efficient and facilitated recycling photocatalysts for HO formation is an ideal strategy for solar-to-chemical energy conversion. In this work, we synthesized ultrathin CN nanosheets through the process of thermal polymerization and polyvinylpyrrolidone (PVP)-assisted solvent exfoliation. Subsequently, the obtained ultrathin CN nanosheets were tightly attached to the surface of TiO arrays, resulting in an enhanced photocatalytic HO production rate. The density functional theory (DFT) calculations demonstrate that an internal electric field (IEF) is generated between the TiO array and the ultrathin CN due to the different work functions. The presence of IEF provides an additional driving force for carrier separation and transfer in the heterointerface. Benefitting from this unique strategy, the optimal heterojunction obtains the highest HO formation rate (2.93 μmol/L/min), which is about 4.1 times than that of TiO arrays. The rotating disk electrode (RDE) analysis manifests HO formation through 2e-dominated oxygen reduction reaction (ORR). This research provides an innovative strategy for assembling a type-II heterojunction with a useful IEF for efficient photocatalytic HO production.
开发用于生成羟基自由基（·OH）的高效且便于回收的光催化剂是太阳能到化学能转换的理想策略。在这项工作中，我们通过热聚合和聚乙烯吡咯烷酮（PVP）辅助的溶剂剥离过程合成了超薄的氮化碳（CN）纳米片。随后，将获得的超薄CN纳米片紧密附着在二氧化钛（TiO₂）阵列的表面，从而提高了光催化生成·OH的速率。密度泛函理论（DFT）计算表明，由于功函数不同，在TiO₂阵列和超薄CN之间产生了内建电场（IEF）。IEF的存在为异质界面中的载流子分离和转移提供了额外的驱动力。受益于这种独特的策略，最佳异质结获得了最高的·OH生成速率（2.93 μmol/L/min），约为TiO₂阵列的4.1倍。旋转圆盘电极（RDE）分析表明·OH是通过2e主导的氧还原反应（ORR）形成的。这项研究为组装具有有用IEF的II型异质结以实现高效光催化生成·OH提供了一种创新策略。
