Research Center for Eco-Environmental Engineering, Dongguan University of Technology, Dongguan, Guangdong 523808, P. R. China.
Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520, United States.
Environ Sci Technol. 2020 Sep 1;54(17):10954-10963. doi: 10.1021/acs.est.0c03800. Epub 2020 Aug 17.
We here present a novel TiO-based electrode loaded with amorphous Pd clusters that achieve efficient anodic destruction of perfluorooctanoic acid (PFOA), a persistent water pollutant with significant environmental and human health concerns. These amorphous Pd clusters were characterized by the disordered, noncrystalline arrangement of Pd single atoms in close proximity, in contrast to crystalline Pd nanoparticles that have been often employed to tailor the electronic properties of an electrode. We found that the TiO electrode loaded with amorphous Pd clusters significantly outperformed the TiO electrode loaded with crystalline Pd particles due to enhanced electron transfer through dominant Pd-O bonds. Combined with the efficient binding of PFOA and its degradation intermediates to the fluorinated electrode surface, this electrode was capable of mineralizing PFOA and releasing fluoride as F. The reaction pathway was found to proceed without involving reactive oxygen species and therefore was not quenched by common anions in complex natural water systems such as chloride ions.
我们在这里展示了一种新型的 TiO 基电极，负载有非晶态 Pd 团簇，可实现高效地阳极破坏全氟辛酸 (PFOA)，这是一种持久性的水污染物质，对环境和人类健康有重大影响。这些非晶态 Pd 团簇的特点是 Pd 单原子的无序、非晶态排列，紧密排列，与通常用于调整电极电子性质的晶态 Pd 纳米颗粒形成对比。我们发现，负载有非晶态 Pd 团簇的 TiO 电极的性能明显优于负载有晶态 Pd 颗粒的 TiO 电极，这是由于通过占主导地位的 Pd-O 键增强了电子转移。结合 PFOA 及其降解中间产物与氟化电极表面的有效结合，该电极能够矿化 PFOA，并将氟以 F-的形式释放。发现反应途径不涉及活性氧物质，因此不会被复杂天然水系统中的常见阴离子（如氯离子）所抑制。
