Enhanced electrocatalytic hydrodechlorination by modulating metal-support interaction and H generation of single-Pd-atom anchored NiFeP electrode

Electrocatalytic hydrodechlorination (EHDC) stands out as an economical and prospective technology for eliminating chlorinated organic pollutants. Single-atom catalyst engineering and metal-support interaction (MSI) offer the promising strategies for developing electrocatalysts with high atom utilization and reactivity. Herein, atomically dispersed palladium (Pd) anchored on the iron (Fe)-introduced nickel phosphide (NiFeP) support is reported. The prepared NiFeP-Pd electrode exhibits outstanding electrocatalytic activity in 4-CP removal efficiency (98.8 %) with an ultra-low dosage of Pd (0.0497 mg cm−2) and the highest reported MA value (446.01 min−1 g−1), surpassing Ni2P-Pd by 6.34 times. Experimental results combined with theoretical calculations suggest that the superior performance of NiFeP-Pd stems from the modulated support by Fe introduction, which not only enhances the generation of adsorbed atomic hydrogen species (H*), but also reduces the energy barrier of C-H formation on Pd sites by regulating the MSI. In addition, single-Pd-atom construction on NiFeP with good conductivity and large specific surface area makes the contributions as well.