Pd, Rh and Ru nanohybrid-catalyzed tetramethyldisiloxane hydrolysis for H2 generation, nitrophenol reduction and Suzuki–Miyaura cross-coupling

Abstract

The hydrolysis of tetramethyldisiloxane, a constituent of silicone industrial refuse, provides a convenient method to generate H₂ on demand. Herein, highly selective and efficient 2D graphene-like carbon nanosheet (GCN)-stabilized Pd, Rh and Ru nanohybrids have been developed as robust catalysts upon hydrolysis of tetramethyldisiloxane for H₂ generation, Suzuki–Miyaura cross-coupling reactions and 4-nitrophenol reduction. The optimal Pd/GCN nanohybrid shows high catalytic activity in H₂ generation from tetramethyldisiloxane hydrolysis with a TOF of 375 min⁻¹ at 30 °C. GCNs surpass other supports (including UIO-66, ZIF-67, ZrO₂, CeO₂ and active carbon) in this Pd nanoparticle catalytic efficiency, highlighting their vital role in H₂ generation. Successive H₂ (or HD) generation/alkene hydrogenation reactions and kinetic isotope effect determination using D₂O confirm that tetramethyldisiloxane hydrolysis involves water O–H bond cleavage in the rate-limiting step and produces H₂ with one H atom provided by H₂O and the other one by tetramethyldisiloxane.