We introduce a new platinum group metal-free (PGM-free) hydrogen oxidation electrocatalyst with superior performance in anodes of alkaline exchange membrane fuel cells (AEMFCs). A carbon-supported bimetallic nickel–molybdenum catalyst was synthesized by thermal reduction of transition metal precursors on the surface of a carbon support (KetjenBlack 600J). The mass-weighted activity of 4.5 A g_Me⁻¹ determined in a liquid electrolyte 0.1 M NaOH using a rotating disk electrode (RDE) technique is comparable to the value reported for Pd/C with a comparable particle size under similar conditions. This NiMo/KB catalyst was integrated in a membrane electrode assembly (MEA) using an alkaline exchange membrane and ionomer. Single AEMFC tests performed in a H₂/O₂ configuration resulted in a record power density output of 120 mW cm⁻² at 0.5 V, the MEA was found to be durable under the conditions of potential hold of 0.7 V for 115 h. For the first time, operando X-ray computed tomography (CT) experiments were performed demonstrating liquid water formation at the PGM-free anode during cell operation, and in situ ambient pressure X-ray photoelectron spectroscopy (APXPS) and X-ray absorption spectroscopy (APXAS) were used to study the role of molybdenum in hydrogen adsorption.

中文翻译：

---

不含铂族金属的NiMo氢氧化催​​化剂：碱性交换膜燃料电池的高性能和耐久性

我们在碱性交换膜燃料电池（AEMFC）的阳极中引入了一种性能优异的新型无铂族金属（无PGM）氢氧化电催化剂。通过热还原碳载体（KetjenBlack 600J）表面上的过渡金属前体，合成了碳载体的双金属镍钼催化剂。使用旋转圆盘电极（RDE）技术在0.1 M NaOH液体电解质中测定的4.5 A g _Me ^-1的质量加权活性与在相似条件下具有可比较粒径的Pd / C的值相当。使用碱性交换膜和离聚物将这种NiMo / KB催化剂整合到膜电极组件（MEA）中。在H ₂ / O _2中执行单个AEMFC测试该配置导致在0.5 V时记录的功率密度输出为120 mW cm ^-2，发现MEA在0.7 V的电势保持115小时的条件下是耐用的。首次进行了操作X射线计算机断层摄影（CT）实验，以证明在电池运行过程中在无PGM的阳极上形成液态水，以及原位环境压力X射线光电子能谱（APXPS）和X射线吸收能谱（APXAS）用于研究钼在氢吸附中的作用。