Titanium carbide MXenes-initiated plasmonic metal-support interaction for effective photocatalysis on uncoated Ag nanoparticles

Localized surface plasmon resonances enable the effective harvesting of visible-light photons and yield energetic electrons and holes on short timescale in plasmonic nanoparticles (NPs). However, the balance between the higher stability (which requires stabilizing ligands) and the higher photocatalytic activity (which prefers a clean surface for adsorbing reactant molecules and diminishing the charge-recombination rate) is still a challenge, limiting the efficiency of light utilization. Herein, we show that by forming uncoated Ag-Ti 3 C 2 nanohybrids via in situ reduction, the photocatalytic performance of plasmonic Ag NPs is promoted with the benefit of plasmonic metal-support interaction with Ti 3 C 2 MXenes. The photodegradation efficiency of the organic pollutant methyl orange is elevated from 1.0% to 96.5% due to the excellent metal-like conductivity of Ti 3 C 2 and Schottky barriers of interfacial Ag-TiO 2-x . This work reveals the assistance of MXenes for stabilizing the illuminated Ag NPs and boosting efficient hot charge carrier separations in direct plasmonic photocatalysis.