Jiang Bo, Xue Hairong, Wang Pei, Du Haoran, Kang Yunqing, Zhao Jingjing, Wang Shengyao, Zhou Wei, Bian Zhenfeng, Li Hexing, Henzie Joel, Yamauchi Yusuke
The Education Ministry Key Lab of Resource Chemistry, Joint International Research Laboratory of Resource Chemistry, Shanghai Frontiers Science Center of Biomimetic Catalysis, College of Chemistry and Materials Science, Shanghai Normal University, Shanghai 200234, China.
International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.
J Am Chem Soc. 2023 Mar 22;145(11):6079-6086. doi: 10.1021/jacs.2c10637. Epub 2023 Feb 28.
Amorphous noble metals with high surface areas have attracted significant interest as heterogeneous catalysts due to the numerous dangling bonds and abundant unsaturated surface atoms created by the amorphous phase. However, synthesizing amorphous noble metals with high surface areas remains a significant challenge due to strong isotropic metallic bonds. This paper describes the first example of a mesoporous amorphous noble metal alloy [iridium-tellurium (IrTe)] obtained using a micelle-directed synthesis method. The resulting mesoporous amorphous IrTe electrocatalyst exhibits excellent performance in the electrochemical N reduction reaction. The ammonia yield rate is 34.6 μg mg h with a Faradaic efficiency of 11.2% at -0.15 V versus reversible hydrogen electrode in 0.1 M HCl solution, outperforming comparable crystalline and Ir metal counterparts. The interconnected porous scaffold and amorphous nature of the alloy create a complementary effect that simultaneously enhances N absorption and suppresses the hydrogen evolution reaction. According to theoretical simulations, incorporating Te in the IrTe alloy effectively strengthens the adsorption of N and lowers the Gibbs free energy for the rate-limiting step of the electrocatalytic N reduction reaction. Mesoporous chemistry enables a new route to achieve high-performance amorphous metalloid alloys with properties that facilitate the selective electrocatalytic reduction of N.
具有高比表面积的非晶态贵金属因其非晶相产生的大量悬空键和丰富的不饱和表面原子而作为多相催化剂引起了广泛关注。然而，由于强烈的各向同性金属键，合成具有高比表面积的非晶态贵金属仍然是一项重大挑战。本文描述了使用胶束导向合成法获得的介孔非晶态贵金属合金[铱 - 碲（IrTe）]的首个实例。所得的介孔非晶态IrTe电催化剂在电化学氮还原反应中表现出优异的性能。在0.1 M HCl溶液中，相对于可逆氢电极，在-0.15 V时氨产率为34.6 μg mg h，法拉第效率为11.2%，优于同类晶体和Ir金属对应物。合金的相互连接的多孔支架和非晶态性质产生了一种互补效应，同时增强了氮的吸附并抑制了析氢反应。根据理论模拟，在IrTe合金中掺入Te有效地增强了氮的吸附，并降低了电催化氮还原反应限速步骤的吉布斯自由能。介孔化学为实现具有促进氮选择性电催化还原性能的高性能非晶态准金属合金开辟了一条新途径。
