Photoluminescence activity of BaTiO3 nanocubes via facile hydrothermal synthesis

Abstract

Free from scaling effect is highly desirable but yet challenging in lead-free BaTiO3 (denoted as BTO). In this work, we revisit the synthesis BTO nanocubes via hydrothermal route and provide an insight on the photoluminescence behavior of BTO nanocubes, whilst others focus on the reproducibility of BTO nanocubes. The crystallinity of the BTOs was enhanced when the as-synthesized powders underwent calcination at elevated temperatures (> 500 °C). A combination of X-ray diffraction (XRD) patterns and transmission electron microscopy (TEM) images affirms that the BTO nanostructures evolved from cubic to tetragonal and changing from pseudo-ellipsoid to nanocube with {100} sharp facets. The tunable optical band gaps (3.18-2.74 eV), Urbach tails in UV-Vis absorption spectra and the enhanced intensity of photoluminescence at violet wavelength (433.7 nm) indicate the presence of localized state. In order to sort out the origin of the localized state, either stems from structural disorder or surface state, time-resolved photoluminescence was carried out. The long decay of the time-resolved photoluminescence (> 100 ns) proves the dominant involvement of self-trapped states. This in turn narrows the band gap, thus facilitates photoluminescence excitation.

Enhancement of microstructure characteristic and dielectric constant of BaMn0.05Ti0.95O3 ceramics

“…The peaks of COO-vibration, indicating the acetate's presence, were observed to decline at 1000°C, which ultimately turned into carbonate during the coprecipitation process [26]. Traces of BaCO3 are the carbonate phase in the sample observed with the appearance of a C-O vibration peak [27]. The peaks of C-O vibration reduced at the higher sintering temperature, indicating carbonate decomposition [28].…”

Shape‐Tunable BaTiO3 Crystals Presenting Facet‐Dependent Optical and Piezoelectric Properties

“…[14,15] Previously, 30-nm BaTiO 3 nanocubes have been synthesized by heating a mixture of bis(ammonium lactate) titanium dihydroxide, Ba(OH) 2 , tert-butylamine, and oleic acid in water to 220 °C for 72 h. [16] Similar reaction conditions, but at a calcination temperature of 1000 °C, were employed to grow edge-truncated BaTiO 3 cubes. [17] However, sharp BaTiO 3 octahedra and BaTiO 3 particles with tunable shapes and adjustable sizes have not been achieved. Thus, facet-dependent properties of this important ceramic material remain unknown.BaTiO 3 crystals can be incorporated with polydimethylsiloxane (PDMS) or other polymers to form a composite matrix for piezoelectric nanogenerator (PENG) fabrication.…”

Efeito dos íons Fe3+ na estrutura de perovskitas à base de titânio obtidas via método hidrotérmico de micro-ondas

“…As emissões nas regiões do violeta e verde do espectro visível estão relacionadas aos defeitos que estão associados aos portadores de carga que se encontram presos em clusters próximos a BC ou a BV. Por sua vez, as emissões nas regiões do amarelo e vermelho do espectro visível estão relacionadas aos defeitos responsáveis por aprisionar os portadores de carga distantes da BC e da BV (HASBULLAH et al, 2019, SOUZA et al, 2014. No caso das amostras de BaTiO3 e SrTiO3 as (LONGO et al, 2008, VERMA et al, 2013.…”