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 C(24)N(24) fullerene, considering different bi-metal distribution patterns for each binary complex, viz. Ti(x)Cu(z)@C(24)N(24), Ti(x)Mn(y)@C(24)N(24), and Mn(y)Cu(z)@C(24)N(24) (with x, y, z = 0–6). We elucidate whether controlling the distribution of bi-metal atoms into the C(24)N(24) cavities can alter their catalytic activity toward CO(2), NO(2), H(2), and N(2) gas capture. Interestingly, Ti(2)Mn(4)@C(24)N(24) and Ti(2)Cu(4)@C(24)N(24) 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.