ABSTRACT
TiO2 is a wide bandgap semiconductor that is earth-abundant, inexpensive, and of great interest for applications involving the capture and utilization of solar energy. –e ability to easily acquire and exploit nanocrystalline TiO2 preparations has created an explosion of interest in high surface area applications such as dye-sensitized solar energy conversion,1 sensing,2 hazardous waste remediation, and photocatalysis,3 particularly photochemical fuel production4 and photolysis of water.5 However, the same high surface-area-to-volume ratio that makes TiO2 nanoparticles desirable for applications results in enormous impact of surface properties that are challenging to control. –e chemical properties of nanocrystalline surfaces and the presence of even small quantities of intrinsic defects and dopants can dictate the optical and electronic properties of powders and £lms of TiO2 nanoparticles. Hence, details of sample preparation and handling can have strong e¢ects on device performance.
