Unique NiS₂-MoS₂ heterostructures with misfit lattices composed of cubic NiS₂, metallic 1 T-MoS₂ and semiconductive 2H-MoS₂ have been immobilized on poly(1-vinyl-3-ethylimidazolium bromide) functionalized polypyrrole/graphene oxide via an ordinary hydrothermal procedure. The obtained NiS₂-MoS₂/PVEIB/PPy/GO nanosheets exhibited the excellent electrocatalytic performance for hydrogen evolution reaction (HER). PVEIB played an essential role in the fabrication of this inorganic/organic hierarchical lamellar micro-/nanostructures, which not only played as a good connector between transition metal dichalcogenides (TMDCs) heterostructures and PPy/GO, inducing the formation of metallic 1 T-MoS₂, but also effectively stabilized more electrons and further facilitate the Heyrovsky reaction for the generation and release of H₂. Though NiS₂ possessed poor conductivity and induced partial 1 T-MoS₂ transformed to 2H-MoS₂ on PVEIB/PPy/GO, the preeminent HER activity was still gained, because NiS₂ could effectively prevent the oxidation of MoS₂ exposed in the atmosphere. Especially, the crystal phase transition of MoS₂ from 1 T to 1 T’ phase in NiS₂-MoS₂/PVEIB/PPy/GO could be detected by XPS after long-term HER test. Therefore, poly(ionic liquid)s and another metal ion would induce the crystal structures of TMDCs and optimize their electrocatalytic performance, which might afford a new thought towards the reasonable design of electrocatalysts based on TMDCs for electrochemical water splitting.

独特的具有错配晶格的NiS ₂ -MoS ₂异质结构由立方NiS ₂，金属1 T-MoS ₂和半导电2H-MoS _2组成，已通过固定在聚（1-乙烯基-3-乙基咪唑鎓溴化物）功能化的聚吡咯/氧化石墨烯上普通的水热程序。所获得的NiS ₂ -MoS ₂/ PVEIB / PPy / GO纳米片对氢气析出反应（HER）表现出出色的电催化性能。PVEIB在这种无机/有机分层层状微/纳米结构的制造中起着至关重要的作用，该结构不仅充当过渡金属二卤化物（TMDCs）异质结构与PPy / GO之间的良好连接体，诱导了金属1 T-MoS的形成₂，还可以有效地稳定更多的电子，并进一步促进Heyrovsky反应生成和释放H ₂。尽管NiS ₂具有差的电导率并在PVEIB / PPy / GO上诱导部分1 T-MoS ₂转化为2H-MoS ₂，但由于NiS ₂仍获得了优异的HER活性。可以有效防止暴露在大气中的MoS ₂的氧化。特别地，在长期的HER测试之后，通过XPS可以检测到NiS ₂ -MoS ₂ / PVEIB / PPy / GO中MoS ₂从1 T到1 T'相的晶体相变。因此，聚离子液体和另一种金属离子将诱导TMDCs的晶体结构并优化其电催化性能，这可能为合理设计基于TMDCs的电化学分解水的电催化剂提供了新的思路。