Synthesis and characterization of manganese-doped zinc orthosilicate phosphor powders

Effects of polyvinylpyrrolidone on structural and optical properties of willemite semiconductor nanoparticles by polymer thermal treatment method

“…This is in conformity with the outcomes of the XRD analysis of this work. The NPs were near hexagonal in shape, similar to those reported by previous researchers [40,61,62].…”

“…Al-Hada et al [59] reported that for a metal oxide semiconductor, there is supposed to be an existing range of prospective emissions attributed to impurities or crystal defects, like exciton band to neutral donor, band-edge recombination, donor to acceptor recombination, exciton band to neutral acceptor, free excitonic transition, excitation from interstitial X to conduction band, interstitial M to valence band, excitation from M vacancy to the valence band, and X vacancy to the valence band. The emission positioned roughly at 485 nm in the blue region is assumed to be due to zinc interstitial and is often referred to as the blue emission [50,62,68]. The green emission observed at 530 and 543 nm is because of the transition between the valence and conduction.…”

Investigation on Structural and Optical Properties of Willemite Doped Mn2+Based Glass-Ceramics Prepared by Conventional Solid-State Method

“…The maximum emission intensity can be observed at 3 wt.% of doping content. Tsai et al reported that the intensity of the emission spectra increased with increasing in Mn content up to 6% and however decreased significantly as the doping increased above 8% [32]. This trend has been attributed to the concentration quenching phenomenon since, at low concentration of dopant ions, the concentration quenching effects are said to be negligible due to relatively large average distance between Mn 2+ ions [33].…”

Characterization of Manganese-doped Willemite Green Phosphor Gel Powders

“…Phosphor powders with composition of Zn 2−x Mn x SiO 4 (x = 0-12.0 mol%) were prepared via a sol-gel process, details of which were described elsewhere [8]. The starting solutions were prepared from zinc chloride, tetraethyl orthosilicate (TEOS), and manganese chloride.…”

“…However, the willemite derived from the previous sol-gel processes is generally crystallized by heating at temperatures higher than 800 o C; and further, it is hard to avoid the segregation of residual zinc oxide phase during firing. The property of gel-derived products is well known that depends strongly on the processing conditions [7], such as solution concentration, [8].…”