Pd anchored on C3N4 nanosheets/reduced graphene oxide: an efficient catalyst for the transfer hydrogenation of alkenes

In this work, a porous g-C3N4 nanosheets/reduced graphene oxide (rGO) composite was synthesized via the hydrothermal co-assembly of GO and g-C3N4 nanosheets (g-C3N4 NS). Compared with g-C3N4 NS, rGO and bulk g-C3N4/rGO, the g-C3N4 NS/rGO supported Pd nanocatalyst displayed a remarkable catalytic activity for the hydrogenation of alkenes with formic acid and formates as the hydrogen source at atmospheric pressure. Among all the as-prepared Pd-g-C3N4 NS/rGO catalysts, the optimized Pd-g-C3N4 NS/rGO20 exhibited the highest turnover frequency of 133 mol mol−1 Pd h−1, which is among the highest value reported in documents. 99% conversion and 99% selectivity were achieved after 30 min reaction at 30 °C for the hydrogenation of nitrobenzene. In addition, Pd-g-C3N4 NS/rGO20 exhibited an excellently high stability after five successive cycles without significant loss of its catalytic activity.