Electrochemical hydrogen evolution reaction (HER) is one of the key techniques for hydrogen production. Much great effort has been made so far to develop highly efficient HER catalysts to replace expensive precious metals (e.g. Pt). Unfortunately, the synthesis processes were generally not cost-effective and/or scalable. So it is highly desirable to develop a facile technique to enhance HER activity of conventional inexpensive but less active materials. In this work, monodispersed tungsten carbide (WC) nanoparticles (<5 nm) were in-situ formed/anchored on nanosized carbon black (CB) and carbon nanotube (CNT) via a simple low temperature molten salt synthesis technique. Owing to this special hybrid structure, both the exposed surface area of active species and the electrical conductivity of the catalysts were increased effectively, making the catalysts perform considerably better in HER than pure WC and WC based catalysts prepared via other conventional routes. WC nanocrystals in-situ formed/anchored on CNTs showed small onset overpotential (90 mV), low Tafel slope (69 mV dec⁻¹), high current density (93.4 and 28 mA cm⁻² at 200 and 300 mV, respectively) and excellent stability (remaining stable even after 3000 cycles). Such a performance is one of the best among those of WC based electrocatalysts developed to date. We demonstrate here significantly improved HER performances of inexpensive tailored WC materials, along with a facile synthesis strategy which could be also readily extended to prepare a range of other types of mono-dispersed nanocatalysts for more potential applications.

电化学放氢反应（HER）是制氢的关键技术之一。迄今为止，为开发高效的HER催化剂来代替昂贵的贵金属（例如Pt）已付出了巨大的努力。不幸的是，合成过程通常不具有成本效益和/或可扩展性。因此，迫切需要开发一种简便的技术来增强常规廉价但活性较低的材料的HER活性。在这项工作中，单分散的碳化钨（WC）纳米颗粒（<5 nm）通过纳米碳黑（CB）和碳纳米管（CNT）原位形成/固定在纳米碳黑（CB）和碳纳米管（CNT）上。一种简单的低温熔融盐合成技术。由于这种特殊的杂化结构，活性物质的暴露表面积和催化剂的电导率均得到有效提高，使得该催化剂在HER中的性能明显优于通过其他常规途径制备的纯WC和WC基催化剂。在CNT上原位形成/固定的WC纳米晶体显示出小的起始过电势（90 mV），低的Tafel斜率（69 mV dec ^-1），高的电流密度（93.4和28 mA cm ^-2）分别在200和300 mV的电压下）和出色的稳定性（即使经过3000次循环仍保持稳定）。这种性能是迄今为止开发的基于WC的电催化剂中最好的性能之一。我们在这里证明了便宜的定制WC材料的HER性能得到了显着改善，同时还提供了一种易于合成的策略，该策略也可以轻松扩展以制备一系列其他类型的单分散纳米催化剂，以用于更多潜在应用。