Tuning Electron Density Endows Fe1–xCoxP with Exceptional Capability of Electrooxidation of Organic Pollutants
At a Glance
Section titled “At a Glance”| Metadata | Details |
|---|---|
| Publication Date | 2019-11-07 |
| Journal | Environmental Science & Technology |
| Authors | Haopeng Feng, Jiangfang Yu, Lin Tang, Guangming Zeng, Wangwang Tang |
| Institutions | Hunan University |
| Citations | 82 |
Abstract
Section titled “Abstract”The good performance of base metal catalysts for the electrooxidation of organic pollutants has attracted great attention. However, base metal phosphides for electrooxidation are seldom studied owing to the sluggish water adsorption and dissociation dynamics, which will hinder the production of the sorbed hydroxyl radicals (M(<sup>•</sup>OH)) and thus inhibit the electrooxidation of organic pollutants. Herein, we proposed a universal strategy to improve the electrooxidation capability of metal phosphides by modulating the surface electron densities. The electron interactions between cobalt (Co) and phosphorus (P) are modulated after iron doping, resulting in more positively charged Co and more negatively charged P, which can promote the adsorption and activation of water molecules and produce large quantities of M(<sup>•</sup>OH). Meanwhile, the experimental results show that the iron-modulated Fe<sub>0.53</sub>Co<sub>0.47</sub>P nanosheet arrays exhibit higher removal efficiency of tetracycline than the boron-doped diamond and Pt anode at low current intensity. Based on experimental results and density functional theory + <i>U</i> calculations (DFT + <i>U</i>), it is found that Fe<sub>0.53</sub>Co<sub>0.47</sub>P has lower barrier (0.45 eV) to form the sorbed hydroxyl radicals (M(<sup>•</sup>OH)) and higher overpotential to produce O<sub>2</sub> than its counterparts, suggesting that Fe<sub>0.53</sub>Co<sub>0.47</sub>P can produce more M(<sup>•</sup>OH) instead of O<sub>2</sub>. The above results highlighted the feasibility of these base metal phosphides for electrooxidation for advanced water purification.