Recent advances in hydrogen evolution reaction catalysts on carbon/carbon-based supports in acid media

The present and future energy demands of burgeoning global population require an energy currency that can be obtained from clean and renewable resources. In this context, hydrogen as the future energy currency is widely considered as the solution to the energy crisis. Efficient electrocatalysis of hydrogen evolution reaction by inexpensive, highly active, abundant, environmental friendly and stable electrocatalyst is vital for the low-cost production of hydrogen. Carbon as the hydrogen evolution reaction catalyst support is explored since the initial period of the United States space program. The importance of carbon as the support material is understood by the fact that hydrogen evolution reaction electrocatalysis demands not only efficient electron transfer at its surface but also effective electron transport within the electrocatalyst. The hydrogen evolution reaction electrocatalysts presented in this review specifically have two components: 1) hydrogen evolution reaction active component and 2) carbon or carbon-based support for the active component. However, when carbon supports are coupled with the hydrogen evolution reaction active materials, the activity of these materials is enhanced significantly. The contribution of carbon support in the enhancement of the catalytic activity is discussed and highlighted by comparing the electrochemical parameters of supported and unsupported electrocatalysts where available.