Sunlight Active Mesoporous Black TiO2 Micro/Nanomotors

Photocatalytic Micro and nanomotors (MNMs) are artificial machines that convert light energy to propulsion and these light-powered machines have garnered considerable attention due to their potential applications in environmental detection/remediation, biomedicine, and microengineering.

Since these machines are light controlled, their direction and velocity of motion can be regulated by modulating the intensity and orientation of the light source and the selection of light source is determined according to the absorption spectrum of the MNMs.

For real-life applications, it is necessary to harvest solar energy directly for the autonomous propulsion of such motors that will pave the way for a unique motor system with enhanced motor skills.

TiO2 is one of the most efficient and most investigated photocatalysts and researches are going on to directly harvest solar energy without using any external light source.

It is necessary to synthesise a material that can harvest the whole solar spectrum containing 5% UV (absorb 200-400nm), 43% Visible (absorb 400-700 nm), and 52% IR (700-2500 nm) energy.

In such a way, to exploit TiO2, its black version, the ‘black TiO2’ with mesoporosity will be implemented here in the form of its janus structural combinations with metals to form MMBT MNMs and bimetallics to form BMBT MNMs in a fuel free environment.

These MNMs will be implemented in photocatalysis of a one component and two component systems, viz. using a single anionic or cationic dye as the target (single component) or a mixture of one anionic and one cationic dye as target (two component). So, the new class of MNMs will pave the way for selective and non-selective photocatalysis.

Overall, STIMULATOR will develop, a new class of materials called ‘direct-sunlight active MNMs’.