The catalytic performance of the catalysts under different conditions is shown in Fig. . A series of controlled experiments were also carried out to clarify the function of each component of the tandem catalyst under different reactant atmospheres (Fig. ). Firstly, to verify the stability of toluene under reaction conditions (320 °C and 2MPa), toluene/N2 was passed through the Fe|3Z5 catalyst bed and the conversion of toluene was less than 0.5%, indicating that almost no chemical reaction occurred when the sole toluene as the reactant. The conversions of CO2/H2/toluene over the Z5 catalyst were all below 0.5%, indicating that neither CO2 hydrogenation nor toluene alkylation reaction happened over the Z5 catalyst.