Wang Fang, Yu Haifeng, Feng Ting, Zhao Dan, Piao Jinhua, Lei Jianfei
School of Environmental Engineering and Chemistry, Luoyang Institute of Science and Technology, Luoyang, China.
State Key Laboratory of Organic-Inorganic Composites, Beijing, China.
Front Chem. 2020 Jun 4;8:422. doi: 10.3389/fchem.2020.00422. eCollection 2020.
Platinum-based alloys with low cost transition metals have been considered as promising electrocatalysts in the field of sustainable energy conversion and storage. Herein, chloroplatinic acid, cobalt chloride, and carbon nanotubes are used as platinum, cobalt precursors, and carriers, respectively, to prepare rich Pt dealloying PtCo nanoparticles (SD-PtCo/CNT) via co-liquid phase reduction and chemical dealloying methods. The characterization and test results confirm that PtCo alloy nanoparticles are evenly dispersed on carbon nanotubes, further dealloying and resulting in the partial dissolving of cobalt, simultaneously generating a rich Pt layer and roughly active surface. Benefiting from the unique structure, the SD-PtCo/CNT catalyst displays obviously enhanced HER activity in both acidic and alkaline conditions. In 1.0 M KOH, SD-PtCo/CNT exhibits a low overpotential of 78 mV at 10 mA/cm and a small tafel slope (38.28 mV/dec). In 0.5 M HSO, SD-PtCo/CNT still shows the superior performance compared with un-dealloying PtCo/CNT, with an overpotential of 17 mV at 10 mA/cm and corresponding tafel slope of 21.35 mV/dec. The high HER activity of SD-PtCo/CNT can be attributed to the formation of a platinum rich layer and the uniformly dispersed PtCo nanoparticles supported on superior conductive carbon nanotubes, suggesting its great potential for hydrogen generation via water splitting.
含低成本过渡金属的铂基合金被认为是可持续能源转换与存储领域中有前景的电催化剂。在此，氯铂酸、氯化钴和碳纳米管分别用作铂、钴前驱体和载体，通过共液相还原和化学脱合金方法制备富铂脱合金化的PtCo纳米颗粒（SD-PtCo/CNT）。表征和测试结果证实，PtCo合金纳米颗粒均匀分散在碳纳米管上，进一步脱合金导致钴部分溶解，同时生成富铂层和大致活性表面。得益于独特结构，SD-PtCo/CNT催化剂在酸性和碱性条件下均表现出明显增强的析氢反应（HER）活性。在1.0 M KOH中，SD-PtCo/CNT在10 mA/cm²时具有78 mV的低过电位和小的塔菲尔斜率（38.28 mV/dec）。在0.5 M H₂SO₄中，与未脱合金的PtCo/CNT相比，SD-PtCo/CNT仍表现出优异性能，在10 mA/cm²时过电位为17 mV，相应的塔菲尔斜率为21.35 mV/dec。SD-PtCo/CNT的高HER活性可归因于富铂层的形成以及负载在高导电性碳纳米管上的均匀分散的PtCo纳米颗粒，表明其在通过水分解产氢方面具有巨大潜力。
