High phase-purity 1T′-MoS2- and 1T′-MoSe2-layered crystals
High phase-purity 1T′-MoS2- and 1T′-MoSe2-layered crystals
复制标题
DOI：
10.1038/s41557-018-0035-6
复制
发表时间：
2018-04
期刊：
影响因子：
21.8
通讯作者：
Yifu Yu;Gwang-Hyeon Nam;Qiyuan He;Xue-jun Wu;Kang Zhang;Zhen Yang;Junze Chen;Qinglang Ma;
中科院分区：
文献类型：
--
作者：
Yifu Yu;Gwang-Hyeon Nam;Qiyuan He;Xue-jun Wu;Kang Zhang;Zhen Yang;Junze Chen;Qinglang Ma;
相控制在无机材料的精确合成中起着重要的作用，因为相结构对导电性和化学稳定性等性质有着深刻的影响。六族过渡金属二卤化物(过渡金属为Mo和W，硫族化合物为S、Se和Te)的电催化性能优于半导体化合物，相控制备一直是其研究的难点。在这里，我们报道了大规模制备微米级金属相1T‘-MoX2(X = S，Se)-高纯层状大块晶体。我们发现1T‘-MoS_2晶体具有扭曲的八面体配位结构，经热退火或激光照射后可转变为2H-MoS_2。电化学测试表明，在酸性介质中，1T‘-MoS2基面比2H-MoS2基面具有更高的析氢活性。
Phase control plays an important role in the precise synthesis of inorganic materials, as the phase structure has a profound influence on properties such as conductivity and chemical stability. Phase-controlled preparation has been challenging for the metallic-phase group-VI transition metal dichalcogenides (the transition metals are Mo and W, and the chalcogens are S, Se and Te), which show better performance in electrocatalysis than their semiconducting counterparts. Here, we report the large-scale preparation of micrometre-sized metallic-phase 1T′-MoX2(X = S, Se)-layered bulk crystals in high purity. We reveal that 1T′-MoS2crystals feature a distorted octahedral coordination structure and are convertible to 2H-MoS2following thermal annealing or laser irradiation. Electrochemical measurements show that the basal plane of 1T′-MoS2is much more active than that of 2H-MoS2for the electrocatalytic hydrogen evolution reaction in an acidic medium.