Song Rui, Chi Haibo, Ma Qiuling, Li Dongfeng, Wang Xiaomei, Gao Wensheng, Wang Hao, Wang Xiuli, Li Zelong, Li Can
Key Laboratory of Advanced Catalysis, Gansu Province, State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu 730000, China.
School of Chemical and Materials Science, University of Science and Technology of China, Hefei, Anhui 230026, China.
J Am Chem Soc. 2021 Sep 1;143(34):13664-13674. doi: 10.1021/jacs.1c05008. Epub 2021 Aug 19.
Photoelectrocatalytic (PEC) degradation of organic pollutants into CO and HO is a promising strategy for addressing ever-growing environmental problems. Titanium dioxide (TiO) has been widely studied because of its good performance and environmental benignancy; however, the PEC activity of TiO catalyst is substantially limited due to its fast electron-hole recombination. Herein, we report a TiO nanocone-based photoelectrocatalyst with superior degradation performance and outstanding durability. The unique conical catalyst can boost the PEC degradation of 4-chlorophenol (4-CP) with 99% degradation efficiency and higher than 55% mineralization efficiency at a concentration of 20 ppm. The normalized apparent rate constant of a nanocone catalyst is 5.05 h g m, which is 3 times that of a nanorod catalyst and 6 times that of an aggregated particle catalyst, respectively. Further characterizations reveal that the conical morphology of TiO can make photogenerated charges separate and transfer more efficiently, resulting in outstanding PEC activity. Moreover, computational fluid dynamics simulations indicate that a three-dimensional conical structure is beneficial for mass transfer. This work highlights that tuning the morphology of a photoelectrocatalyst at the nanometer scale not only promotes the charge transfer but also facilitates the mass transportation, which jointly enhance the PEC performance in the degradation of persistent pollutants.
将有机污染物光电催化（PEC）降解为二氧化碳和水是解决日益严重的环境问题的一种很有前景的策略。二氧化钛（TiO₂）因其良好的性能和环境友好性而受到广泛研究；然而，TiO₂催化剂的PEC活性由于其快速的电子-空穴复合而受到很大限制。在此，我们报道了一种具有优异降解性能和出色耐久性的基于TiO₂纳米锥的光电催化剂。这种独特的锥形催化剂能够促进对4-氯苯酚（4-CP）的PEC降解，在20 ppm的浓度下，降解效率达到99%，矿化效率高于55%。纳米锥催化剂的归一化表观速率常数为5.05 h⁻¹ g⁻¹ m²，分别是纳米棒催化剂的3倍和团聚颗粒催化剂的6倍。进一步的表征表明，TiO₂的锥形形态能够使光生电荷更有效地分离和转移，从而产生出色的PEC活性。此外，计算流体动力学模拟表明三维锥形结构有利于传质。这项工作突出了在纳米尺度上调整光电催化剂的形态不仅能促进电荷转移，还能促进质量传输，这共同提高了在降解持久性污染物方面的PEC性能。
