Preparation method of water phase CdTe/CdSe core-shell quantum dots for rapid fingerprint appearance

[0028] Example 1

[0029] Fixed condition: [Cd 2+ :TGA:Te=1:3:0.1], pH=8, [Te:Se=1:0.4]

[0030] (1). Preparation of cadmium precursor solution

[0031] Take 0.46g CdCl 2 ·2.5H 2 Dissolve O in 240ml deionized water, put it in a 500ml three-necked round bottom flask, seal it, and pass N 2 After stirring for 15 min, 0.01 ml of thioglycolic acid [Cd 2+ :TGA=1:3] was added to a three-necked round-bottomed flask, and then adjusted to pH=8 with 2M NaOH to obtain [Cd-TGA] 2+ Colorless transparent solution.

[0032] (2). Preparation of tellurium source and selenium source solution:

[0033] Preparation of NaHTe: Weigh 0.12g NaBH 4 Put it in a ground-mouth reaction bottle, add 2ml of deionized water to dissolve, and use N 2 The reaction flask was purged for 5 min. Then weigh 0.06g Te powder [NaBH 4 :Te=3:1] into the reaction bottle, quickly cap the bottle stopper, put it into a 60~80℃ water bath and react for 10~20min until the solution is colorless and transparent to obtain Na

[0041] Example 2

[0042] Change different Te:Se ratios

[0043] [Cd 2+ :TGA:Te=1:3:0.1], pH=8, [Te:Se=1:3]

[0044] (1). The preparation of cadmium precursor solution is the same as that of Example 1 (1)

[0045] (2). The preparation of tellurium source and selenium source solution is the same as that of Example 1 (2)

[0046] (3). Water-phase synthesis of CdTe solution is the same as in Example 1 (3)

[0047] (4). Water-phase synthesis of CdTe / CdSe with core-shell structure:

[0048] Take 100ml of the CdTe solution prepared in step (3) and place it in a three-necked reaction flask, then take 7.5ml of Na prepared in step (2) 2 SeSO 3 [Te:Se=1:3], sealed through N 2 , and heated to reflux for 0.5 h to obtain a CdTe / CdSe quantum dot solution with a core-shell structure.

[0049] (5). The steps of fingerprint development are the same as those of Example 1(5). The fingerprints appear and the color is red.

[0050] Example 3

[0051] Change different pH and Te:Se ratio

[0052] [Cd 2+ :TGA:Te=1:3:0.1], pH=11, [Te:Se=1:0.4]

[0053] (1). Preparation of cadmium precursor solution

[0054] Take 0.46g CdCl 2 ·2.5H 2 Dissolve O in 240ml deionized water, put it in a 500ml three-necked round bottom flask, seal it, and pass N 2 After stirring for 15 min, 0.01 ml of thioglycolic acid [Cd 2+ :TGA=1:3] into a three-necked round-bottomed flask, and then adjust pH=11 with 2M NaOH to obtain [Cd-TGA] 2+ Colorless transparent solution.

[0055] (2). The preparation of tellurium source and selenium source solution is the same as that of Example 1 (2)

[0056] (3). Water-phase synthesis of CdTe solution is the same as in Example 1 (3)

[0057] (4). Water-phase synthesis of CdTe / CdSe with core-shell structure:

[0058] Take 100ml of the CdTe solution prepared in step (3) and place it in a three-necked reaction flask, then take 1ml of Na prepared in step (2) 2 SeSO 3 [Te:Se=1:0.4], sealed