Paramagnetic active sites boosted hydrogenation of p-nitroaniline over prCeO2 supported Pt catalysts.

Developing efficient catalysts for p-nitroaniline hydrogenation under green conditions is pivotal for sustainable chemical synthesis. Herein, we report a Pt catalyst supported on a self-made prCeO2 support that achieves >99% yield in the hydrogenation of p-nitroaniline to p-phenylenediamine under exceptionally green conditions (35 °C, 5 mg catalysts, 69 mg substrate, H2 balloon, 10 h, 2 mL methanol solvent). The superior performance is linked to paramagnetic active sites at the Pt-prCeO2 interface, generated at an optimal reduction temperature of 400 °C, and enhanced hydrogen spillover via their unpaired electrons. After reusing it 20 times, it still retains 50% of its original performance. This work introduces paramagnetic active sites as a novel strategy for catalysis chemistry and synthesis.