Encapsulating MAl2O4:Eu2+, Dy3+ (M=Sr, Ca, Ba) phosphors with triethanolamine to enhance water resistance

Improved performance of surface functionalized TiO2/activated carbon for adsorption–photocatalytic reduction of Cr(VI) in aqueous solution

“…As confirmed on the spectrum recorded on TiO 2 /AC-DETA, stretching vibration of CQO and CO-N in secondary amide groups are observed at 1625 and 1382 cm À 1 [25], with the N-H bending vibration at 1512 cm À 1 [26], C-H stretching vibrations at 1306 cm À 1 [16], and C-N stretching vibrations at 1141 cm À 1 [27]. It is notable that, the CQO ( $ 1650 cm À 1 ) and C-N ($1000 cm À 1 ) stretching in tertiary amide groups [28,29] were not observed in the spectrum, indicating that the DETA were attached on AC by the amidation preferentially between AC-COCl and NH 2 groups in DETA. The peaks assigned to CQO, CO-N and C-O-Ti on TiO 2 /AC-DETA intensified obviously by comparing to the corresponding one on TiO 2 /AC, suggesting the attaching of -COOH by acid oxidation of AC and sequent amidation between AC-COCl and DETA, as well as the interfacial esterification between AC-COCl and Ti-OH.…”

Ag nanoparticles significantly improve the slow decay brightness of SrAl2O4:Eu2+,Dy3+ by the surface plasmon effect

“…According to previous reports, SAO is a kind of easily hydrolyzed long afterglow luminescence material and can hydrolyze completely within 4 hours. 40 In addition, AgNP on the surface of SAO are easily oxidized when exposed for a long time. To protect the surface of AgNP in SAO and improve the stability of Ag/SAO, the Ag/SAO-3 sample was coated at different mass fractions of SiO 2 on the condition of basically not changing the afterglow performance.…”

Chemically engineered persistent luminescence nanoprobes for bioimaging

“…As discussed in the previous example, strontium aluminate hydrolyzes in water to form non luminescent aluminum hydroxide precipitate and soluble strontium hydroxide 134. Several approaches have been investigated to improve water stability of strontium aluminate including encapsulation with silica by sol-gel or precipitation techniques, direct reaction with phosphoric acid, and encapsulation with triethanolamine 135. Due to the wide use of trialkoxysilanes in bioconjugate chemistry and their high compatibility with silica surfaces, the authors used a modified Stöber process to form a silica shell around the phosphors.…”