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demonstrated to increase the CO 2 adsorption capacity of SnO 2 quantum wires, so as to enhance the current density and Faradaic efficiency (FE) for formate in CO 2 electrochemical reduction. [20] As another example, O-vacancy-engineered InO x nanoribbons were developed to catalyze the CO 2 into formate with the best selectivity of up to 91.7% as well as high partial current densities over a wide range of potentials. [21] Apart from the construction of defects, engineering the electrical conductivity is another method to increase the performance of CO 2 electrochemical reduction. [22][23][24][25] For instance, the chemical coupling interaction between porous In 2 O 3 nanobelts and reduced graphene oxide (rGO) resulted in 3.6-fold enhancements in specific current density for formate relative to the In 2 O 3 nanobelts physically loaded onto rGO at -1.2 V vs reversible hydrogen electrode (vs RHE). [26] In addition, mesoporous SnO 2 nanosheets supported on conductive carbon cloth exhibited a remarkable partial current density (≈45 mA cm 2 ) in the electrochemical reduction of CO 2 into formate. [27] Taken together, integrating the defect engineering and conductivity promotion represents a promising way to improve the performance of CO 2 electrochemical reduction.Herein, we hybridized the defective SnS 2 nanosheets and Ag nanowires for the efficient electrochemical reduction of CO 2 into formate and syngas. Due to the similar Fermi level of SnS 2 nanosheets and Ag nanowires, the free electrons in Ag nanowires were able to promote the electronic transport of SnS 2 nanosheets, resulting in the 5.5-fold larger carrier density of Ag-SnS 2 hybrid nanosheets than that of SnS 2 nanosheets. Due to the abundant defect sites and carrier density, the Ag-SnS 2 hybrid nanosheets exhibited a maximum FE of 83.8% for carbonaceous product at -0.9 V vs RHE. Notably, at -1.0 V vs RHE, the Ag-SnS 2 hybrid nanosheets displayed 38.8 mA cm −2 of geometrical current density in CO 2 electrochemical reduction, 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. The mechanistic study revealed that the hybridization of the defective SnS 2 nanosheets and Ag nanowires not only promotes the conductivity of electrocatalyst, but also increases the binding strength for CO 2 , which benefited the CO 2 activation and reduction.Small 2019, 15, 1904882 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 exhibited a maximum FE of 83.8% for carbonaceous product at -0.9 V vs RHE. In addition, at -1.0 V vs RHE, the Ag-SnS 2 hybrid nanosheets displayed 38.8 mA cm −2 in CO 2 electrochemical reduction, 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. Our work provides a successful example of integrating the defect engineering and conductivity promotion for improving the electrocatalytic performance toward CO 2 reduction.