Kusada Kohei, Wu Dongshuang, Yamamoto Tomokazu, Toriyama Takaaki, Matsumura Syo, Xie Wei, Koyama Michihisa, Kawaguchi Shogo, Kubota Yoshiki, Kitagawa Hiroshi
Division of Chemistry , Graduate School of Science , Kyoto University , Kitashirakawa Oiwake-cho, Sakyo-ku , Kyoto 606-8502 , Japan . Email:
Department of Applied Quantum Physics and Nuclear Engineering , Kyushu University , 744 Motooka, Nishi-ku , Fukuoka 819-0395 , Japan.
Chem Sci. 2018 Dec 4;10(3):652-656. doi: 10.1039/c8sc04135k. eCollection 2019 Jan 21.
The electronic structure of surface atoms has a great effect on catalytic activity because the binding energy of reactants is closely related to the electronic structure. Therefore, designing and controlling the local density of states (LDOS) of the catalyst surface would be a rational way to develop innovative catalysts. Herein, we first demonstrate a highly active AuIr solid-solution alloy electrocatalyst for the oxygen reduction reaction (ORR) by emulating the Pt LDOS profile. The calculated LDOS of Ir atoms on the AuIr(111) surface closely resembled that of Pt(111), resulting in suitable oxygen adsorption energy on the alloy surface for the ORR. We successfully synthesized AuIr solid-solution alloys, while Ir and Au are immiscible even above their melting points in the bulk state. Although monometallic Ir or Au is not active for the ORR, the synthesized AuIr alloy demonstrated comparable activity to Pt at 0.9 V a reversible hydrogen electrode.
表面原子的电子结构对催化活性有很大影响，因为反应物的结合能与电子结构密切相关。因此，设计和控制催化剂表面的局域态密度（LDOS）将是开发创新型催化剂的合理途径。在此，我们通过模拟Pt的LDOS分布，首次展示了一种用于氧还原反应（ORR）的高活性AuIr固溶体合金电催化剂。计算得出的AuIr(111)表面Ir原子的LDOS与Pt(111)的非常相似，从而在合金表面产生了适合ORR的氧吸附能。我们成功合成了AuIr固溶体合金，而在体相中即使高于熔点，Ir和Au也是不互溶的。尽管单金属Ir或Au对ORR没有活性，但合成的AuIr合金在相对于可逆氢电极0.9 V时表现出与Pt相当的活性。
