Plasmon enhanced visible light photocatalytic activity in polymer-derived TiN/Si-O-C-N nanocomposites

Highlights: • Controlled size and in situ crystallization of TiN nanocrystals in an amorphous Si-O-C-N matrix is achieved through PDC route. • Plasmonic properties of TiN nanocrystals were exploited towards degradation of organic dyes in visible light for the first time. • The photodegradation rate constant was found to be 4.2 x 10^-3 min^-1. • Reactive species trapping experiments suggests that hydroxyl radicals play a major role in the degradation of MB. Herein, we provide a detailed insight into the precursor chemistry, precursor-to-material transformation and characterization of nanocomposites made of a TiN nanophase and a Si-O-C-N ceramic. The polymer-derived ceramics (PDCs) route applied to synthesize these nanocomposites resulted in the formation of nanocrystals less than 4 nm in size and the calculated lattice parameter value for the nanocrystals (a = 0.4239 nm) matched the theoretical value of TiN (a = 0.4241 nm). The Si-O-C-N ceramic served as a platform for anchoring TiN nanocrystals. As a proof of concept, we have attempted to exploit the plasmonic properties of nanocomposites to achieve photocatalytic degradation of organic dyes. The absorption spectra clearly showed plasmonic resonance in the visible region with peak positioned around 670 nm according to the presence of TiN nanocrystals which resulted in the enhancement of dye degradation.