Linking Bi-Metal Distribution Patterns in Porous Carbon Nitride Fullerene to Its Catalytic Activity toward Gas Adsorption.

Immobilization of two single transition metal (TM) atoms on a substrate host opens numerous possibilities for catalyst design. If the substrate contains more than one vacancy site, the combination of TMs along with their distribution patterns becomes a design parameter potentially complementary to the substrate itself and the bi-metal composition. By means of DFT calculations, we modeled three dissimilar bi-metal atoms (Ti, Mn, and Cu) doped into the six porphyrin-like cavities of porous CN fullerene, considering different bi-metal distribution patterns for each binary complex, TiCu@CN, TiMn@CN, and MnCu@CN (with x, y, z = 0-6). We elucidate whether controlling the distribution of bi-metal atoms into the CN cavities can alter their catalytic activity toward CO, NO, H, and N gas capture. Interestingly, TiMn@CN and TiCu@CN complexes showed the highest activity and selectively toward gas capture. Our findings provide useful information for further design of novel few-atom carbon-nitride-based catalysts.