Water dissociation in CNT-supported IrO2 nanoparticles

Abstract

Quantum chemical modeling of iridium oxide nanoparticles—(IrO2)n, n = 1, 2, 3—adsorbed on(5, 5) carbon nanotubes (CNTs) is presented. Energetic, geometric, and electronic aspects havebeen analyzed in depth to understand the main features of the nanoparticles in the gas phase andthe adsorption process involved. Covalent Ir–C bonding resulted from the interaction of the(IrO2 )1 and (IrO2)3 particles with the CNT. To evaluate the performance of the material, thedissociation of water into H(ads) and OH(ads) has been investigated. Our results revealed that theintrinsic charge polarization of the iridium oxide clusters favors the water dissociation process,with low activation energies. Moreover, the nanoparticles remain stable and maintain covalentinteractions with the CNT surface during the water dissociation process.