Structural and photoluminescence properties of SnO2 obtained by thermal oxidation of evaporated Sn thin films

Controlled hybridization of Sn–SnO2 nanoparticles via simple-programmed microfluidic processes for tunable ultraviolet and blue emissions

“…Thus, the unequivocal quantum-size effects and the electron density in shells can be greatly enhanced in Sn@SnO 2 nanorods due to highly crystalline metallic tin cores and a few tiny crystalline doping amorphous SnO 2 shells with the thickness near the exciton Bohr radius of SnO 2 (2.7 nm). [25][26][27][28][29]51 Other peaks can be possibly ascribed to some structural defects or luminescent centers of different energy levels (e.g., oxygen vacancies, tin interstitials or dangling). 30,[48][49][50] Interestingly, nanospheres with distinct core-shell morphology (Fig.…”

“…23,25,26 However, it is very challenging to synthesize free nanoparticles (NPs) with unequivocal quantum-size effects and controlled defects since most current processes suffer from difficulties in fabricating the desired hybrid nanostructures and/or controlling sizes at the exciton Bohr radius of SnO 2 ($2.7 nm). [25][26][27][28][29] The overgrown sizes and out-of-control of microstructures in SnO 2 NPs usually lead to asymmetric, broad and/or multiplex emissions in the optical range. 23,24,[30][31][32] UV emissions at room temperature were only observed in some hybrid SnO 2 nanostructures, such as the thin lm with SnO 2 nanocrystal doping in the amorphous matrix excited by the 325 nm laser line, 23 the 100 nm SnO 2 nanowires coated with amorphous shells of $1.5 nm thick excited at the 355 nm wavelength, 33 the 100-200 nm SnO 2 nanowires conned on p-type silicon wafers excited at the 325 nm laser line.…”

Spin‐Coated Bismuth Vanadate Thin Film as an Alternative Electron Transport Layer for Light‐Emitting Diode Application

“…[ 52 ] The observed oxygen vacancies indicate a significant influence of defects present in the films. The defect density N of the films can be calculated from Smakula's formula as follows [ 53 ] where the value of the refractive index ( n ) considered for BiVO 4 is 2.76 (ideal system), [ 54 ] the oscillator strength of optical transmission ( f ) is 1, and αW 1/2 is the area of the PL emission peak fitted by Gaussian curve fitting method. [ 53 ] The calculated defect density plotted as a function of solution concentration is shown in Figure 7b.…”

“…[52] The observed oxygen vacancies indicate a significant influence of defects present in the films. The defect density N of the films can be calculated from Smakula's formula as follows [53] N ¼ 1.29 Â 10 17 n f ðn 2 þ 2Þ 2 αW 1=2 (3) where the value of the refractive index (n) considered for BiVO 4 is 2.76 (ideal system), [54] the oscillator strength of optical transmission ( f ) is 1, and αW 1/2 is the area of the PL emission peak fitted by Gaussian curve fitting method. [53] The calculated defect density plotted as a function of solution concentration is shown in Figure 7b.…”

Size-controlled synthesis of porous ZnSnO3 nanocubes for improving formaldehyde gas sensitivity

“…41 The emission peak at 437 nm is attributed to the Sn interstitials. 42,43 The emission at 446 nm is attributed to the transition from shallow donors (oxygen vacancies) to the valence band. 43,44 The existence of oxygen vacancies promotes the formation of adsorbed oxygen, 45 which in turn promotes the reaction of the gas and the adsorbed oxygen, and ultimately improves the sensitivity of the sensor.…”