Developing diatomic catalysts (DACs) for the CO2 reduction reaction (CO2RR) has emerged as a promising leading-edge research area owing to their maximum atomic utility and more sophisticated functionalities. However, the proper design of DACs at an atomic level and an understanding of the synergistic mechanism of binary sites remain challenging. Herein, an N-rich carbon matrix with precisely controlled Ni/Cu dual sites is synthesized through the assistance of metal–organic frameworks. The as-prepared catalyst presents high CO Faradaic efficiency of over 95% from −0.39 to −1.09 V vs reversible hydrogen electrode (RHE) with the maximum value of 99.2% at −0.79 V vs RHE and long-term durability of 60 h electrolysis. Density functional theory studies reveal that the electronic redistribution and band gap narrowing induced by the adjacent NiN4 and CuN4 moieties enhance the electron conductivity and strengthen the bonding interactions between *COOH intermediates and Ni centers, thus lowering the overall reaction barriers and promoting CO generation.

The diatomic catalysts (DACs) provide a new strategy for efficient catalysis of CO2 reduction reaction (CO2RR) owing to their maximum atomic utility and more flexible active sites. However, it is...

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In this study, graphene-modified asphalt (GMA) was prepared from SK-70# matrix asphalt and ethylene bis(stearamide) (EBS). Based on the uniform design method, a model was created using Data Processing System (DPS) software and First Optimization (1stOpt) software using the graphene mixing amount, EBS mixing amount, shear rate, shear time, and shear temperature as factors and using the asphalt penetration, softening point, force ductility, SHRP-PG test, and multistress creep recovery data as indices. Calculations and analysis showed that the optimal composition and preparation parameters of GMA are as follows: the graphene proportion is 20‰, the EBS proportion is 1%, the shear rate is 6000 r.p.m., the shear time is 180 min, and the shear temperature is 140 °C. The prepared GMA had a significantly improved softening point, low-temperature fracture energy, antirutting factor, and creep recovery rate, indicating that adding graphene can improve the high- and low-temperature performance of asphalt. The prepared GMA was characterized by X-ray diffraction (XRD). The dispersibility of graphene in asphalt was evaluated by fluorescence microscopy and Image-Pro Plus imaging software. The results show that graphene can exist in asphalt in a stable form, which increases the loose-layered structure of stacked asphalt or gum. The intense adsorption effect of graphene strengthens the ordered structure of asphalt. However, due to its dispersibility characteristics, some graphene exists in asphalt in clustered form. When the graphene-to-dispersant ratio approaches the optimal value, the dispersant changes the form of graphene in asphalt from irregular clusters to regular clusters and from large, distinct clusters to small, indistinct clusters. When dispersant cannot uniformly disperse graphene in asphalt, graphene clusters primarily form medium-sized grains.

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