Solvothermal synthesis, luminescence and energy transfer of Dy3+ and Sm3+ doped NaLa(WO4)2 nanocubes

NaLaW2O7(OH)2(H2O): Crystal Structure and RE3+ Luminescence in the Pristine and Annealed Double Tungstates (RE = Eu, Tb, Sm, and Dy)

“…Milli-Q filtered water (resistivity of ∼18 MΩ cm) was used throughout the experiments. The synthesis of the crystalline NaLaW 2 O 7 (OH) 2 (H 2 O) product was performed by the following procedure . First, 6 mL of a Na 2 WO 4 solution (1.0 mol/L) was dropwise added to 20 mL of a La­(NO 3 ) 3 solution (0.1 mol/L; 3:1 WO 4 2– :La 3+ molar ratio) under magnetic stirring at room temperature, followed by adjusting the pH with dilute NaOH and HNO 3 solutions to 8 while keeping the total volume at 70 mL.…”

“…11−13 The potential application of ARE(WO 4 ) 2 has been demonstrated in the multifaceted areas of bioimaging [PEG-NaGd-(WO 4 ) 2 :Eu], 14 biosensors [Na(Gd,Eu)(WO 4 ) 2 ], 15 photothermal therapy (PTT) [NaY(WO 4 ) 2 :Sm 3+ /Nd 3+ ], 16 photocatalysis, 17 light-emitting diodes (LEDs) [NaGd(WO 4 ) 2 :Pr 3+ ], 18 and temperature sensing [NaY(WO 4 ) 2 :Er 3+ /Yb 3+ ]. 19 The synthesis of ARE(WO 4 ) 2 compounds can be achieved by a number of methodologies, including solid-state reaction, 18 sol−gel and Pechini-type sol−gel, 9 molten salt growth, 20 microwave-assisted processing 21,22 and hydrothermal/solvothermal reaction, 10,23 as also summarized in the review article by Kaczmarek and van Deun. 24 Though the hydrothermal and solvothermal techniques are widely acknowledged to be capable of directly generating inorganic solids of controlled phase structure and crystallite morphology within a short amount of reaction time, they frequently yielded unknown products (precursors) for the RE 3+ −tungstate reaction system.…”

“…We believe that the outcome of this work may enrich our understanding of the RE 3+ −WO 4 2− reaction and have wide implications for the hydrothermal crystallization of other RE tungstates and even molybdate analogues. 23 First, 6 mL of a Na 2 WO 4 solution (1.0 mol/L) was dropwise added to 20 mL of a La(NO 3 ) 3 solution (0.1 mol/L; 3:1 WO 4 2− :La 3+ molar ratio) under magnetic stirring at room temperature, followed by adjusting the pH with dilute NaOH and HNO 3 solutions to 8 while keeping the total volume at 70 mL. After homogenization for 30 min, the mixture was transferred to a Teflon-lined stainless steel autoclave with a 100 mL capacity for reaction for 24 h in an electric oven preheated to 100 °C.…”

“…The synthesis of ARE­(WO 4 ) 2 compounds can be achieved by a number of methodologies, including solid-state reaction, sol–gel and Pechini-type sol–gel, molten salt growth, microwave-assisted processing , and hydrothermal/solvothermal reaction, , as also summarized in the review article by Kaczmarek and van Deun . Though the hydrothermal and solvothermal techniques are widely acknowledged to be capable of directly generating inorganic solids of controlled phase structure and crystallite morphology within a short amount of reaction time, they frequently yielded unknown products (precursors) for the RE 3+ –tungstate reaction system.…”

White light emission from single-phase Y2MoO6: xPr3+ (x = 1, 2, 3 and 4 mol%) phosphor

“…Based on the results obtained by single-phase phosphors [16,17], researchers developed numerous surveys about the production of white emitters using single host matrix. Shang et al [18] mentioned four possible methods to obtain white light in single-phase dies: (i) emission in white can be generated from the doping of only one type of rare earth in the matrix [14]; (ii) white light can be generated by combining multiple rare earth ions with simultaneous different emissions: red, green and blue; yellow and blue (such as Ho 3+ / Yb 3+ / Tm 3+ , Tm 3+ / Tb 3+ / Eu 3+ [19,20]; (iii) the emission of white light can be generated by the association of ions in pairs based on the energy transfer mechanism (Eu 3+ / Tb 3+ , Tm 3+ / Er 3+ , Tm 3+ / Ho 3+ , Dy 3+ /Eu 3+ , Dy 3+ /Sm 3+ ) [21][22][23][24][25][26][27] and (iv) luminescent materials related to electronic defects may also emit white light [28].…”