Hybridization of Defective Tin Disulfide Nanosheets and Silver Nanowires Enables Efficient Electrochemical Reduction of CO 2 into Formate and Syngas

Integrating the defect engineering and conductivity promotion represents a promising way to improve the performance of CO 2 electrochemical reduction. Herein, the hybridized composite of defective SnS 2 nanosheets and Ag nanowires is developed as an efficient catalyst for the production of formate and syngas toward CO 2 electrochemical reduction. The Schottky barrier in Ag‐SnS 2 hybrid nanosheets is negligible due to the similar Fermi level of SnS 2 nanosheets and Ag nanowires. Accordingly, the free electrons of Ag nanowires participate in the electronic transport of SnS 2 nanosheets, and thus give rise to a 5.5‐fold larger carrier density of Ag‐SnS 2 hybrid nanosheets than that of SnS 2 nanosheets. In CO 2 electrochemical reduction, the Ag‐SnS 2 hybrid nanosheets display 38.8 mA cm −2 of geometrical current density at –1.0 V vs reversible hydrogen electrode, including 23.3 mA cm −2 for formate and 15.5 mA cm −2 for syngas with the CO/H 2 ratio of 1:1. A mechanistic study reveals that the abundant defect sites and carrier density not only promote the conductivity of the electrocatalyst, but also increase the binding strength for CO 2 , which account for the efficient CO 2 reduction.