Single Metal Atoms Anchored on Nanostructured Diamond for Electrochemical Carbon Dioxide Reduction under Ambient Conditions
DescriptionAs a greenhouse gas, the increasing CO2 in the atmosphere has a profound impact on global climate change. Capturing and reutilizing CO2, in addition to curbing the reliance on fossil fuels, is an effective strategy to decrease the atmospheric concentration of CO2. For recycling CO2, the electrochemical reduction of CO2 is a promising approach. However, the conversion efficiency and selectivity of the current electrochemical CO2 reduction processes are still unsatisfactorily enslaved by the weak CO2 adsorption on the active sites of an electrocatalyst and the difficulty in C=O cleavage there. Developing an electrocatalyst with high-efficiency active sites for promoting CO2 reduction reaction (CO2RR) has thus important scientific and application values for the advance of thetechnique. Basically, an ideal CO2RR electrocatalyst should possess high intrinsic catalytic reactivity and selectivity toward CO2RR, large active surface, and outstanding mechanical and chemical stabilities. Single-atom catalysts (SACs) of selected transition metals hosted on carbon substrates have emerged as a promising system for CO2RR because of the maximal atom utilization (approximate to 100%) and the resultant high efficiency. As a distinctive member of carbon family, sp3-configurated diamond has a series of inherent properties favorable for electrocatalytic CO2RR, particularly a large electrochemical window in comparison with other sp2 carbon phases, which enables to suppress the competitive hydrogen evolution reaction and thus to achieve a high CO2RR selectivity. In this project, we propose to develop a new high-efficiency SAC for CO2 conversion through loading single metal atoms (M, M=Fe, Co, and Ni) on nanostructured and boron-doped diamond films. The basic idea is to endow diamond with good electrical conductivity and large active area through doping and surface nanostructuring, respectively; and the atomically dispersed metal atoms will be anchored through coordination with surface modified N- or O-containing groups on diamond surface. The effects of the factors such as the doping level and surface nanostructure of diamond, the type of metals, and the loading amount and coordination structure of metal atoms, on the CO2RR performance will be elucidated. Through comprehensive characterization and theoretical simulation, the preferential binding sites of metal atoms, the origin of CO2RR activity of SACs/diamond and the corresponding reaction paths will be demonstrated. Implementation of this project will provide further understanding for the design and development of new diamond-based SACs for high-efficiency CO2RR and promote the advance of CO2 conversion technology.
|Effective start/end date||1/01/21 → …|