This study reports the development of a P, S co-doped porous hollow nanotube array (CoNiPS@CF) for high-performance chloride-ion storage. The CoNiPS@CF electrode, synthesized by in situ growth of CoNiOH nanoarrays on pretreated carbon felt (pCF) and subsequent P and S doping, exhibits superior capacitive deionization (CDI) performance. The porous hollow nanotube structure and synergistic effect of P and S doping enhance ion diffusion kinetics and reduce passivation layer formation, leading to high desalination capacity (76.1 mgCl⁻ g⁻¹), fast desalination rate (6.33 mgCl⁻ g⁻¹ min⁻¹), and excellent cycling stability (capacity retention >90%). The introduction of sulfur reduces the passivation layer on CoNiP, improves electrode conductivity, and enhances surface electrochemical activity, further accelerating adsorption kinetics. The study provides a strategy to improve the reactivity and stability of transition metal phosphides for chloride capture and electrochemical dechlorination technologies.This study reports the development of a P, S co-doped porous hollow nanotube array (CoNiPS@CF) for high-performance chloride-ion storage. The CoNiPS@CF electrode, synthesized by in situ growth of CoNiOH nanoarrays on pretreated carbon felt (pCF) and subsequent P and S doping, exhibits superior capacitive deionization (CDI) performance. The porous hollow nanotube structure and synergistic effect of P and S doping enhance ion diffusion kinetics and reduce passivation layer formation, leading to high desalination capacity (76.1 mgCl⁻ g⁻¹), fast desalination rate (6.33 mgCl⁻ g⁻¹ min⁻¹), and excellent cycling stability (capacity retention >90%). The introduction of sulfur reduces the passivation layer on CoNiP, improves electrode conductivity, and enhances surface electrochemical activity, further accelerating adsorption kinetics. The study provides a strategy to improve the reactivity and stability of transition metal phosphides for chloride capture and electrochemical dechlorination technologies.