Cui Zhibo, Ren Zhanghao, Ma Chao, Chen Bowen, Chen Guanzhen, Lu Ruihu, Zhu Wei, Gan Tao, Wang Ziyun, Zhuang Zhongbin, Han Yunhu
Institute of Flexible Electronics (IFE), Northwestern Polytechnical University, Xi'an, 710072, China.
School of Chemical Sciences, The University of Auckland, Auckland, 1010, New Zealand.
Angew Chem Int Ed Engl. 2024 Jul 8;63(28):e202404761. doi: 10.1002/anie.202404761. Epub 2024 Jun 3.
Ruthenium (Ru) is considered a promising candidate catalyst for alkaline hydroxide oxidation reaction (HOR) due to its hydrogen binding energy (HBE) like that of platinum (Pt) and its much higher oxygenophilicity than that of Pt. However, Ru still suffers from insufficient intrinsic activity and CO resistance, which hinders its widespread use in anion exchange membrane fuel cells (AEMFCs). Here, we report a hybrid catalyst (RuCo)/N-CNT consisting of dilute RuCo alloy nanoparticles and atomically single Ru and Co atoms on N-doped carbon nanotubes The catalyst exhibits a state-of-the-art activity with a high mass activity of 7.35 A mg . More importantly, when (RuCo)/N-CNT is used as an anode catalyst for AEMFCs, its peak power density reaches 1.98 W cm, which is one of the best AEMFCs properties of noble metal-based catalysts at present. Moreover, (RuCo)/N-CNT has superior long-time stability and CO resistance. The experimental and density functional theory (DFT) results demonstrate that the dilute alloying and monodecentralization of the exotic element Co greatly modulates the electronic structure of the host element Ru, thus optimizing the adsorption of H and OH and promoting the oxidation of CO on the catalyst surface, and then stimulates alkaline HOR activity and CO tolerance of the catalyst.
钌（Ru）因其与铂（Pt）相似的氢结合能（HBE）以及比Pt更高的氧亲合力，被认为是碱性氢氧化反应（HOR）的一种有前景的候选催化剂。然而，Ru仍然存在固有活性不足和抗CO能力差的问题，这阻碍了其在阴离子交换膜燃料电池（AEMFC）中的广泛应用。在此，我们报道了一种由稀RuCo合金纳米颗粒以及氮掺杂碳纳米管上的原子级单Ru和Co原子组成的混合催化剂（RuCo）/N-CNT。该催化剂展现出了最先进的活性，质量活性高达7.35 A mg。更重要的是，当（RuCo）/N-CNT用作AEMFC的阳极催化剂时，其峰值功率密度达到1.98 W cm，这是目前基于贵金属的催化剂中AEMFC的最佳性能之一。此外，（RuCo）/N-CNT具有优异的长期稳定性和抗CO能力。实验和密度泛函理论（DFT）结果表明，外来元素Co的稀合金化和单原子分散极大地调节了主体元素Ru的电子结构，从而优化了H和OH的吸附，并促进了催化剂表面CO的氧化，进而提高了催化剂的碱性HOR活性和CO耐受性。
