Metal–Carbon Hybrid Electrocatalysts Derived from Ion‐Exchange Resin Containing Heavy Metals for Efficient Hydrogen Evolution Reaction

Transition metal–carbon hybrids have been proposed as efficient electrocatalysts for hydrogen evolution reaction (HER) in acidic media. Herein, effective HER electrocatalysts based on metal–carbon composites are prepared by controlled pyrolysis of resin containing a variety of heavy metals. For the first time, Cr 2 O 3 nanoparticles of 3–6 nm in diameter homogeneously dispersed in the resulting porous carbon framework (Cr–C hybrid) is synthesized as efficient HER electrocatalyst. Electrochemical measurements show that Cr–C hybrids display a high HER activity with an onset potential of −49 mV (vs reversible hydrogen electrode), a Tafel slope of 90 mV dec −1 , a large catalytic current density of 10 mA cm −2 at −123 mV, and the prominent electrochemical durability. X‐ray photoelectron spectroscopic measurements confirm that electron transfer occurs from Cr 2 O 3 into carbon, which is consistent with the reported metal@carbon systems. The obtained correlation between metals and HER activities may be exploited as a rational guideline in the design and engineering of HER electrocatalysts.