Xie Junyang, Huang Danyang, Yin Huiming, Liu Feng, Ding Yi
Tianjin Key Laboratory of Advanced Functional Porous Materials, Institute for New Energy Materials and Low-Carbon Technologies, School of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384, China.
Yunnan Precious Metal Provincial Laboratory Co., Ltd., Kunming 650106, China.
ACS Appl Mater Interfaces. 2022 Aug 10;14(31):35466-35476. doi: 10.1021/acsami.2c04350. Epub 2022 Jul 27.
Metallic Pd is widely recognized as an efficient electrocatalyst for the formic acid oxidation reaction (FAOR), which unfortunately suffers from poor durability owing to Pd dissolution and CO poisoning. The present work describes an effective method to enhance Pd durability by alloying with Cu and Au. Cu could provide surface OH at low potentials to remove poisonous CO for improved CO resistance. Au, the most inert metal, was added to reduce Pd and Cu dissolution. Moreover, alloying with Cu and Au could also modulate the electronic structure of Pd which is just profitable for the FAOR. The constructed PdCuAu with a nanoporous structure exhibits a specific activity of 14.9 mA cm and a Pd mass activity of 6012 A g, which is ∼15 times and ∼14 times higher than those of commercial Pd/C. While these two electrocatalysts were used as fuel cell anodes, the maximum power density of the PdCuAu anode (Pd loading 10 μg cm) is 93.2 mW cm and the value of the Pd/C anode (Pd loading 1.2 mg cm) is 60.3 mW cm. The power efficiency of Pd has been notably increased by 185 times in this home-made nanoporous PdCuAu ternary alloy electrocatalyst.
金属钯被广泛认为是甲酸氧化反应（FAOR）的高效电催化剂，但不幸的是，由于钯的溶解和一氧化碳中毒，其耐久性较差。目前的工作描述了一种通过与铜和金合金化来提高钯耐久性的有效方法。铜可以在低电位下提供表面羟基以去除有毒的一氧化碳，从而提高抗一氧化碳能力。添加最惰性的金属金以减少钯和铜的溶解。此外，与铜和金合金化还可以调节钯的电子结构，这对甲酸氧化反应是有利的。构建的具有纳米多孔结构的钯铜金表现出14.9 mA cm的比活性和6012 A g的钯质量活性，分别比商业钯碳高约15倍和约14倍。当将这两种电催化剂用作燃料电池阳极时，钯铜金阳极（钯负载量为10 μg cm）的最大功率密度为93.2 mW cm，钯碳阳极（钯负载量为1.2 mg cm）的值为60.3 mW cm。在这种自制的纳米多孔钯铜金三元合金电催化剂中，钯的功率效率显著提高了185倍。
