Metal hydroxide hybridized Pd catalysts via in-situ etching for high current density and pH-universal hydrogen evolution reaction

• Published in: Applied surface science 2024-09, Vol.668, p.160397, Article 160397
• Main Authors: Li, Tonghui, Zheng, Tao, Hui, Tianli, Pan, Jinbo, Zhang, Rui, Liu, Haiyan, Liu, Zhichang, Xu, Chunming, Meng, Xianghai
• Format: Article
• Language: English
• Subjects: High current density; Low-temperature etching; Optimized electronic structure; pH-universal HER; Superhydrophilic and aerophobic surface
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2024.160397

[Display omitted] •A method has been designed for the low-temperature, low-pressure in-situ etching coupled with electro-deposition for the preparation of HER catalysts.•The synergistic effect of Fe and Pd optimizes the Pd-H binding energy.•The synergistic effect of Ni(OH)2, Fe(OH)3 and Pd facilitates the dynamical process in HER. The development of highly efficient and innovative electrocatalysts is crucial for the commercialization of the hydrogen evolution reaction (HER) at high current densities. An electrocatalyst consisting of Pd nanoparticles electrodeposited on nickel foam (NF) treated with ferric chloride etching, yielding a Pd content of 0.53 wt%, was synthesized. This PdFe/NF-24 h catalyst demonstrated outstanding HER performance across a wide pH range, requiring overpotentials of only 302 mV, 96.4 mV and 637.9 mV to achieve a current density of 1000 mA/cm2 in 1 M KOH, 0.5 M H2SO4 and 1 M Phosphate Buffer Saline (PBS) electrolytes, respectively. The ferric chloride etching increased the active surface area, while iron doping optimized the hydrogen adsorption free energy on Pd. Furthermore, the presence of metal hydroxides facilitated the dissociation of water into adsorbed hydrogen, which then bound to active sites on the Pd surface to produce hydrogen, thereby enhancing the efficiency of hydrogen production. The catalyst operated at 1000 mA/cm2 in 1 M KOH solution for 222 h without degradation; it maintained stability for 124 h in 30 % KOH solution; in 0.5 M H2SO4 solution, it retained 99.6 % performance for 77 h and it remained stable for 230 h in 1 M PBS solution.