Recent developments in the use of TiO2 nanostructures for photoluminescence-based oxygen sensing

Titanium dioxide (TiO2) nanoparticles are at the base of different important applications including solar energy conversion, heterogeneous photocatalysis, environmental remediation and many others. Understanding and control... [ view full abstract ]

Titanium dioxide (TiO2) nanoparticles are at the base of different important applications including solar energy conversion, heterogeneous photocatalysis, environmental remediation and many others. Understanding and control of TiO2 properties is, thus, extremely important in view of development of new technological devices or improvement of existing ones. Ambient-controlled photoluminescence (PL) analysis is a tool that provides important information on TiO2 photo-physical characteristics, while also representing a possible multi-parametric route to chemical sensing.
In this contribution some recent findings on the feasibility of the use of TiO2 for efficient and multi-parametric oxygen sensing are shown. We report some of our recent findings in the optimization of optical oxygen sensors performances, through:

a) quasi 1-D hierarchical nanostructures of TiO2, for which we obtained unconventional sensitivities in the field of PL-based oxygen sensing.

b) ratiometric approach by means of mixed-phase TiO2 and the simultaneous detection of well separated-PL emissions of the two crystalline phases;

Our findings pointed out the potentialities of optical sensing for future double-parametric optical sensing by titania thanks to multiple response obtained toward a same analyte and possibly paved the way for selective detection towards chemical species carried in air.