Title : One-step strategy to maximize single-atom catalyst utilization in nitrate reduction via bidirectional optimization of mass transfer and electron supply
Abstract:
Single-atom catalysts offer exceptional performance but face practical challenges due to complex synthesis and low efficiency caused by mass transfer resistance. In this study, based on a simple one-step pyrolysis method, we designed a Cu single-atom catalyst with high active site exposure and a locally electron-deficient environment (HE Cu1–N4) to achieve maximum utilization efficiency in electrocatalytic nitrate reduction (NO3RR). Using advanced
characterization techniques, we confirmed that its unique 3D structure enhances Cu atom exposure and reduces nitrate (NO3 –) mass transfer resistance. Synchrotron radiation and DFT calculations showed that adjusting the coordination environment induces a local electrondeficient effect in Cu atoms, increasing the electrostatic attraction to NO3 –. HE Cu1–N4 achieved 100% NH3 selectivity across a wide range of NO3 – concentrations, with an NH3 yield (5.09 mg h–1 mgcat –1) nearly 7-fold higher than that of the conventional unmodified Cu singleatomcatalyst (Cu1–N2, 0.73 mg h–1 mgcat –1). Under pilot-scale conditions, HE Cu1–N4 demonstrated strong resistance to interference and excellent stability in complex water systems. A simple modification method enhanced the utilization efficiency of single atoms in single-atom catalysts, significantly improving the catalytic activity of the material. Moreover, this straightforward synthesis strategy holds promise for the large-scale production of singleatom catalysts, paving the way for practical engineering applications.
