Highly selective IrMo/TiO2 catalyst for hydrogenation of nitroarenes

•The promoter role of Mo in IrMo/TiO2 was presented in selective hydrogenation of 3-NS.•Mo(V) species was found as the active sites for the adsorption of nitro group of 3-NS.•Ir species was the active sites for the activation of H2.•The synergistic effects boost the selectivity of 3-VA.•The optimal catalyst displayed 99.8% selectivity of 3-VA at a 100% conversion.