Regulating the Catalytic Performance of Single-Atomic-Site Ir Catalyst for Biomass Conversion by Metal–Support Interactions

Metal–support interactions are of significance in clarifying the support–activity relationship over deposited metal catalysts yet rarely considered on single-atomic-site species. Herein, using two single-atomic-site Ir samples supported by the defective metastable phase of titanium dioxide or mesoporous graphitic carbon nitride as the research objects, we demonstrate the effects of metal–support interactions on regulating the geometric and electronic structures of the central Ir species, through which, the catalytic properties are further affected. Experimental results show that the single-atomic-site Ir catalyst supported by the defective metastable phase of titanium dioxide exhibits excellent catalytic performance for the hydrogenation of furfural to furfuryl alcohol, showing outstanding conversion (99%), high selectivity (99%), and good stability that are superior to the mesoporous graphitic carbon nitride supported single-atomic-site Ir sample as well as Ir nanoparticles. First-principles simulations reveal that the excellent catalytic performance of the single-atomic-site Ir on the defective metastable phase of titanium dioxide can be attributed to the appropriate strength of interactions between the active metal sites and the reactant molecules owing to the regulation of the supports.