Investigations of EPR Parameters of MgTiO3:Cr3+, SrTiO3:Cr3+, and SrTiO3:Mn4+ Crystals

Synthesis of K2SiF6:Mn4+ Phosphor from SiO2 Powders via Redox Reaction in HF/KMnO4 Solution and Their Application in Warm‐White LED

“…The PL spectrum was obtained by exciting at λ ex = 460 nm. The sharp red emission spectrum comprises five main peaks, locating at 608, 613, 630, 635, and 647 nm, respectively, which should be assigned to transitions between the vibronic levels of the 2 E g and 4 A 2g states, and is similar to the spectrum of K 2 SiF 6 :Mn 4+ phosphor prepared with wet chemical etching of Si wafer, which was typically observed in some Mn 4+ ‐activated phosphors . As recent studies about the complex K 2 SiF 6 :Mn 4+ reported by Adachi and Takahashi, the main peaks at ~608, 613, 630, 635, and 647 nm are due to transitions of the v 4 ( t 1u ), v 6 ( t 2u ), v 6 ( t 2u ), v 4 ( t 1u ), and v 3 ( t 1u ) vibrational levels of the ground state, respectively.…”

Composite Sr2TiO4/SrTiO3(La,Cr) heterojunction based photocatalyst for hydrogen production under visible light irradiation

“…1.979. 35 The EPR intensity of Cr 3+ in these samples is in the order SrTiO 3 (La,Cr) z Sr 2 TiO 4 (La,Cr) < Sr 2 TiO 4 /SrTiO 3 (La,Cr). This further demonstrates that the Sr 2 TiO 4 /SrTiO 3 (La,Cr) composite photocatalyst has a lower amount of Cr 6+ formed not only on the surface, but also in the bulk.…”