Semiconductor Nanostructures (SCNSs) are of great interest due to their
excellent optical and electronic properties. As a result of their unique properties,
semiconductor nanostructures have found applications in several fields, including
optoelectronics, solar energy conversion, photocatalysis, and sensing. SCNSs show
promising prospects in photocatalytic and sensing applications. Photocatalytic
application of SCNSs provides potential solutions for environmental remediation and
energy generation. Several strategies have been developed to achieve high efficiency
for photocatalytic processes using semiconductor nanostructures. Efforts have also
been made to achieve high sensitivities in sensing applications using SCNSs. In the
present chapter, the photocatalysis activity of semiconductor nanostructures has been
discussed along with the photocatalytic mechanism and strategies for enhancing
photocatalytic efficiency. Several applications of semiconductor photocatalysis in
wastewater treatment, hydrogen production, and air purification are cited in recent
literature. The sensing applications of semiconductor nanostructures have also been
discussed, including their use as chemical sensors, gas sensors, and biosensors.
Keywords: Biosensors, Fluorescence sensors, Gas sensors, Photocatalysts, Photocatalytic efficiency, Semiconductor nanostructures.