高熵合金金属烯用于酸性条件下全水分解  

High-entropy alloy metallene for highly efficient overall water splitting in acidic media

作　　者：张丹 石月 陈希磊 赖建平 黄勃龙 王磊[1,2] Dan Zhang;Yue Shi;Xilei Chen;Jianping Lai;Bolong Huang;Lei Wang(State Key Laboratory Base of Eco‐Chemical Engineering,International Science and Technology Cooperation Base of Eco‐chemical Engineering and Green Manufacturing,College of Chemistry and Molecular Engineering,Qingdao University of Science and Technology,Qingdao 266042,Shandong,China;Shandong Engineering Research Center for Marine Environment Corrosion and Safety Protection,College of Environment and Safety Engineering,Qingdao University of Science and Technology,Qingdao 266042,Shandong,China;Department of Applied Biology and Chemical Technology,the Hong Kong Polytechnic University,Hung Hom,Kowloon,Hong Kong SAR,China)

机构地区：[1]青岛科技大学化学与分子工程学院,生态化工国家重点实验室基地,生态化工程与绿色制造国际科技合作基地,山东青岛266042 [2]青岛科技大学环境与安全工程学院,山东省海洋环境腐蚀与安全防护工程研究中心,山东青岛266042 [3]香港理工大学应用生物及化学科技学系,中国香港九龙999077

出　　处：《Chinese Journal of Catalysis》2023年第2期174-183,共10页催化学报（英文）

基　　金：国家自然科学基金(22001143,52072197);山东省高校青年创新技术基金(2019KJC004);山东省杰出青年基金(ZR2019JQ14);泰山学者青年专家计划(tsqn201909114,tsqn201909123);山东省优秀青年基金(ZR2020YQ34);重大科技创新项目(2019JZZY020405);山东省自然科学基金重大基础研究项目(ZR2020ZD09).

摘　　要：质子交换膜水电解槽(PEMWE)因其在低温下的高效率和高功率密度,成为新一代电解槽的发展方向.在水的电解过程中,设计高效稳定的析氢反应(HER)和析氧反应(OER)催化剂是进一步提高电解槽应用的前提.根据HER和OER“火山型”分布曲线,贵金属(Ir,Ru等)依然是主要的基准电催化剂.对于酸性条件下全水分解,Ir基和Ru基双功能催化剂仍然是最常见的选择.然而,与Ir基催化剂相比,Ru基催化剂在酸性条件下的高溶解速率易导致催化剂快速失活,大大降低了其实际应用价值.目前,酸性条件下全水分解的Ir基催化剂也取得了一些成果,如合金(如PdCu/Ir,Au@AuIr_(2),IrTe纳米棒和IrNi合金纳米花)、钙钛矿(如AIrO_(3))、硒化物(如Li-IrSe_(2))和团簇(如Ir纳米团簇,IrNi纳米团簇)等.然而,Ir基材料在高电流密度下仍然面临质量活性低和稳定性有限的挑战(100 mA cm^(-2)时的过电位超过420 mV,酸性整体水分解在高电流密度下的长期稳定性差).上述问题使得电催化剂无法满足PEMWE的应用要求.因此,开发具有优异电化学活性和稳定性的新型Ir基电催化剂成为当务之急.近年来,至少由五种元素组成的高熵合金(HEAs)材料具有在极端条件下的硬度、韧性、腐蚀性和热稳定性等的强耐受性,因而引起了研究者的广泛兴趣.同时,不同组分的可控性也赋予了HEAs固有的晶格畸变和可调电子结构的协同效应,在催化领域也发挥着重要作用.目前,尚未见使用HEAs催化剂进行酸性条件下全水分解的相关报道.从形貌上看,金属烯具有表面金属原子体积比大、表面金属缺陷丰富、稳定性较好等优点,从而表现出较好的催化性能.因此,结合HEAs协同效应和金属烯结构优点的电催化剂,有望解决酸性条件下全水分解电催化剂的设计问题.本文成功制备了具有丰富的无定形和晶体结构的IrPdRhMoW HEA金属烯作为一种高效的双功能电催化剂,用The preparation of stable and efficient acidic overall water splitting catalysts is crucial to advance the progress of proton exchange membrane water electrolyzers.Herein,we successfully prepared IrPdRhMoW HEA metallene with rich amorphous and crystalline structures.In 0.5 mol L^(-1)H_(2)SO_(4),the extraordinary catalytic performance(the overpotentials for hydrogen evolution(HER)and oxygen evolution(OER)of IrPdRhMoW/C at 10 mA cm^(-2)are 15 mV and 188 mV,respectively)is far stronger than that of commercial catalysts(HER:Pt/C,47 mV and OER:RuO_(2),305 mV)and even other reported noble metal-based catalysts.Using IrPdRhMoW/C for the overall water splitting,only a cell voltage of 1.48 V is required to achieve 10 mA cm^(-2)and 1.59 V required to achieve 100mA cm^(-2),which is the best voltage under high current density reported so far.More importantly,the IrPdRhMoW/C still maintains excellent electroactivity and structural stability after 100 h of water splitting at 100 mA cm^(-2).Theory calculations reveal the self-balanced effect of electronic structures in the HEA due to the co-existence of crystalline and amorphous lattice structures.The strong orbital couplings not only maximize the electro activity towards both HER and OER but also stabilize the valence states of metal sites for durable electrocatalysis.

关 键 词：高熵合金 金属烯 结晶/非晶 全水解 酸性介质 

分 类 号：O643.36[理学—物理化学] TQ116.2[理学—化学]