LDHs-based bifunctional electrocatalyst for effective tunable syngas generation via CO2 reduction

Electrocatalytic reduction of CO2 into syngas (CO and H2) has been recognized to be a promising approach to achieve carbon neutrality. However, producing syngas with tunable H2/CO ratios in a wide range is still challenging. Herein, nitrogen doped graphene aerogel (GA) supported both single-atomic Ni and Ni nanoparticles (NPs) with a surface atomic ratio of 1.11 were constructed by using layered double hydroxide (LDHs) and g-C3N4 as Ni and N precursors, respectively. H2 and CO are the only products of CO2 electroreduction and the ratio of H2/CO can be tuned from 0.4 to 2.5 by changing applied potentials. In addition, the catalyst exhibits a large CO Faradaic efficiency (74%) and good long-term stability (12 h) at a relatively small potential (−0.67 V vs. RHE). This study will shed a new light on the construction of bifunctional catalysts for efficient tunable syngas generation via electroreduction of CO2.