Adsorbate-Mediated Deposition of Noble-Metal Nanoparticles on Carbon Substrates for Electrocatalysis

Here, we demonstrate a general method of mediating the deposition of metal nanostructures on carbon substrates via reductive adsorbates. The adsorbates, quinone molecules, can achieve a well-defined surface coverage on a range of carbon substrates through one step of soaking. Upon electrochemical reduction, the adsorbates can function as surface-confined reductants to reduce metal cations for uniform anchorage of metal nanoparticles on carbon, which is not easily achievable via other electrochemical deposition. We apply the method to deposition of Ag and Pt and show the close correspondence between the coverage of the adsorbate and the amount of deposition as well as the dependence of the deposit structures on the quinone molecular structures. We further demonstrate the stability and the catalytic activity of the deposited Pt for catalyzing the hydrogen evolution reaction.