Developing catalysts with high activity and high atom utilization as well as exploring catalytic active sites are the biggest challenges for the electrocatalytic hydrodechlorination technology. Herein, a novel strategy of Pd crystal transformation induced by in-situ doping was proposed, and a series of amorphous Pd–P nanoparticles (NPs) with controllable coordination environment were synthesized successfully. The amorphous Pd–P NPs catalyst exhibits the highest activity for electrocatalytic hydrodechlorination and good cycling stability when the Pd–P coordination number is 3 and the Pd–Pd coordination number is 4. The 4-chlorophenol hydrodechlorination efficiency of Pd–P-60 NPs reaches 100 % within 2 h, and the mass activity is 8.58 min⁻¹ g⁻¹, which is 5.57 times as high as that for crystalline Pd NPs catalyst. Theoretical calculation shows that Pd–P catalyst facilitates the desorption of phenol and weakens the toxic effect on active sites. Density of states indicate that the doping of P results in a downshift of d-band center, facilitating the desorption of phenol. This work discovers the crystal effect and coordination effect of amorphous Pd–P NPs for electrocatalytic hydrodechlorination, which lays an important theoretical foundation for the design and development of high-performance Pd-based catalysts for electrocatalytic hydrodechlorination.

开发具有高活性和高原子利用率的催化剂以及探索催化活性位点是电催化加氢脱氯技术的最大挑战。本文提出了一种新的原位掺杂诱导的Pd晶体转变的策略，并成功地合成了一系列可控配位环境的非晶Pd-P纳米粒子。当Pd-P配位数为3且Pd-Pd配位数为4时，无定形Pd-P NPs催化剂表现出最高的电催化加氯活性和良好的循环稳定性。Pd-P-60 NPs的4-氯苯酚加氢脱氯效率2 h内达到100％，质量活度为8.58 min ^-1 ·g ^-1，是晶体Pd NPs催化剂的5.57倍。理论计算表明，Pd-P催化剂促进了苯酚的解吸，减弱了对活性位点的毒性作用。状态的密度表明，P的掺杂导致d带中心的下移，从而促进苯酚的解吸。这项工作发现了无定形Pd-P NPs用于电催化加氢脱氯的晶体效应和配位效应，这为设计和开发高性能Pd基电催化加氢脱氯催化剂奠定了重​​要的理论基础。