Pd nanocrystals modified Ni foam electrode (Pd NCs/Ni) with Pd loading of 12.5 μg cm⁻² was prepared via electrodeposition and exhibited higher mass activity in the electrochemical hydrodechlorination. With the assistance of polyvinylpyrrolidone and bromide ion, Pd nanocrystals with abundant catalytic sites were uniformly anchored on both the inner and surfaces of the Ni foam. Six chlorophenols were rapidly dechlorinated to phenol using Pd NCs/Ni with high conversion (> 98%) and selectivity (∼ 100%). Pd NCs/Ni showed broad applicability to various reaction conditions and maintained stable activity over 12 consecutive cycles. The electrochemical hydrodechlorination follows the indirect dechlorination mechanism. Hydrogenolysis between adsorbed H and chlorophenols is the rate-controlling step. Low coordination Pd atoms on the faces of Pd (220) and Pd (311) are the main catalytic sites. The study provides a valuable insight of high performance and low cost Pd modified electrode and its catalytic mechanism in electrochemical hydrodechlorination.

^{通过电沉积制备 Pd 负载量为 12.5 μg cm -2}的 Pd 纳米晶体修饰的 Ni 泡沫电极 (Pd NCs/Ni)，并在电化学加氢脱氯中表现出更高的质量活性。在聚乙烯吡咯烷酮和溴离子的帮助下，具有丰富催化位点的钯纳米晶体均匀地固定在泡沫镍的内部和表面。使用 Pd NCs/Ni 以高转化率 (> 98%) 和选择性 (~ 100%)将六种氯酚快速脱氯为苯酚。Pd NCs/Ni 显示出对各种反应条件的广泛适用性，并在 12 个连续循环中保持稳定的活性。电化学加氢脱氯遵循间接脱氯机理。吸附的 H 和氯酚之间的氢解是速率控制步骤。Pd(220)和Pd(311)面上的低配位Pd原子是主要的催化位点。该研究为高性能、低成本的钯修饰电极及其在电化学加氢脱氯中的催化机理提供了有价值的见解。