Hybridization of Defective Tin Disulfide Nanosheets and Silver Nanowires Enables Efficient Electrochemical Reduction of CO₂ into Formate and Syngas

Abstract

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.

Au Nanocrystals@Defective Amorphous MnO2 Nanosheets Core/Shell Nanostructure with Effective CO2 Adsorption and Activation toward CO2 Electroreduction to CO

“…The oxygen vacancies and particular nanocrystals/nanosheets core/shell nanostructure of Au NCs@a-MnO 2 -60 NSs determined their most negative potential of OH – adsorption among these five catalysts. Correspondingly, the highest binding strength of *CO 2 •– in Au NCs@a-MnO 2 -60 NSs effectively stabilizes *CO 2 •– intermediate . The poor stabilization of *CO 2 •– intermediates on the surfaces of Au NCs@c-MnO 2 NSs and c-MnO 2 NSs engendered their low FE CO and strong competition of the HER.…”

Recent Progress of Sn‐Based Derivative Catalysts for Electrochemical Reduction of CO2

“…Similarly, the defect sites of Sn‐based sulfides also promote the catalyst performance. Zhu and coworkers [ 78 ] designed and synthesized a composite Ag nanowire and a defective SnS 2 nanosheet catalyst. Metal Ag nanowires increased the carrier density of the SnS 2 catalyst.…”

1D/2D Heterostructured Photocatalysts: From Design and Unique Properties to Their Environmental Applications

“…Nowadays, the top objectives of human development policy are to achieve sustainable production of clean energy and protect the ecological environment. [1][2][3][4][5][6] In the past few years, 1D nanowires/ nanotubes and 2D nanosheets have been extensively investigated as photocatalysts in the field of environmental protection and sustainable energy development due to their interesting…”

“…Nowadays, the top objectives of human development policy are to achieve sustainable production of clean energy and protect the ecological environment. [ 1–6 ] In the past few years, 1D nanowires/nanotubes and 2D nanosheets have been extensively investigated as photocatalysts in the field of environmental protection and sustainable energy development due to their interesting functions in nanoelectronics and optoelectronics. [ 7–14 ] 1D nanostructures could provide quick charge transfer along their axes, whereas 2D nanostructures (contain layered metal chalcogenides and MXenes) could confine electrons in their unique atomic layers.…”