Highly stable colloidal TiO2 nanocrystals with strong violet-blue emission

Electronic properties of TiO2-based materials characterized by high Ti3+ self-doping and low recombination rate of electron–hole pairs

“…PL spectra of anatase TiO 2 materials are usually attributed to three kinds of physical origins: self-trapped excitons, oxygen vacancies and surface states (defects). 41 Steady-state PL spectra of investigated samples with excitation wavelength at 325 nm are reported in Fig. 6.…”

Whispering Gallery Mode Assisted Enhancement in the Power Conversion Efficiency of DSSC and QDSSC Devices Using TiO2 Microsphere Photoanodes

“…PL spectra of P25-TiO 2 and FμS-TiO 2 consist of two major broad peaks, one ∼425 nm and another at ∼520 nm (Figure a). In general, PL spectral responses in TiO 2 are attributed to self-trapped excitons, oxygen vacancies, and surface defect states. − The green emission in the visible region mainly originates from the oxygen vacancies created in TiO 2 due to mixed valence states of Ti 4+ and Ti 3+ in anatase . The presence of trace quantities of Ti 3+ and oxygen vacancy (V O ) can be inferred from the resonant absorption of unpaired spins using electron paramagnetic resonance (EPR) and X-ray photoelectron spectroscopy (XPS) studies (Figures S3,S4 in the Supporting Information).…”

Whispering Gallery Mode Enabled Efficiency Enhancement: Defect and Size Controlled CdSe Quantum Dot Sensitized Whisperonic Solar Cells

“…Both spectra show two broad peaks ~425 nm and 520 nm respectively. The first peak centered at ~425 nm in PL spectra is ascribed to self-trapped excitations and the peak centered at 520 nm is ascribed to defect related trap states 52 , 53 . The PL spectra of SμS-TiO 2 exhibit multiple spikes on top of the broad peaks observed similar to that of P25-TiO 2 .…”