Energy self-sufficient high-efficiency photo-thermal evaporative nano-particle porous membrane, preparation method and application thereof

1. A method for preparing a high-efficiency photothermal evaporative nano-particle porous membrane, comprising steps as follows:

(1), dissolving polymer A in solvent B to obtain solution A; and dripping solution A into solvent C to obtain a polymer A nano hydrogel dispersion;

(2), evenly mixing polymer A nano hydrogel dispersion and nano particle dispersion of photothermal conversion material D to obtain a co-blended dispersion; performing suction-filtering to the co-blended dispersion on a surface of a solvent-resistant membrane E to form an A-D co-blended membrane; and

(3), performing suction-filtering to a solvent F using the A-D co-blended membrane, and drying to obtain a high-efficiency photothermal evaporative nano-particle porous membrane;

wherein the polymer A in the step (1) comprises at least one selected from a group of polymethyl methacrylate (PMMA), polyether sulphone and polyvinylidenefluoride;

the solvent B in the step (1) is at least one selected from a group of tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, dichloromethane and acetone;

the solvent C in the step (1) is at least one of water and ethanol;

the photothermal conversion material D in the step (2) is at least one of polypyrrole (PPy), polyaniline and poly dopamine;

the solvent-resistant membrane E is a nylon microfiltration membrane, a polyvinylidene fluoride microfiltration membrane or a polytetrafluoroethylene microfiltration membrane;

the solvent F in the step (3) is at least one selected from a group of tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, dichloromethane and acetone; and

the polymer A nano hydrogel dispersion and the nano particle dispersion of photothermal conversion material D in the step (2) are used in an amount proportioned according to a mass ratio of the polymer A:the photothermal conversion material D=16−120:3.

2. The method for preparing a high-efficiency photothermal evaporative nano-particle porous membrane according to claim 1 , wherein the solvent B in the step (1) is used in an amount of the polymer A:the solvent B=0.1−1 g:100 mL.

3. The method for preparing a high-efficiency photothermal evaporative nano-particle porous membrane according to claim 1 , wherein:

the dripping in the step (1) is carried out in a dripping speed of 4-6 mL/min;

the mixing in the step (2) is ultrasonic co-blending; and

the drying in the step (3) is carried out at 55-65° C.

4. The method for preparing a high-efficiency photothermal evaporative nano-particle porous membrane according to claim 1 , wherein in the step (1), dissolving the polymer A in the solvent B is carried out under heating condition so as to dissolve the polymer A in solvent B.

5. The method for preparing a high-efficiency photothermal evaporative nano-particle porous membrane according to claim 1 , wherein the nano particle dispersion of photothermal conversion material D in the step (2) is prepared as follows:

dissolving polyvinylpyrrolidone and ferric chloride in water to obtain homogeneous solution;

adding monomer for reaction, washing, and dispersing in water by ultrasonic to obtain the nano particle dispersion of the photothermal conversion material D.

6. The method for preparing a high-efficiency photothermal evaporative nano-particle porous membrane according to claim 5 , wherein:

the ferric chloride is anhydrous ferric chloride;

the ferric chloride is used in a mass amount equal to more than 6 times a mass of polyvinylpyrrolidone;

the monomer is pyrrole;

the monomer is used in an amount of 1/5-1/15 of a mass of anhydrous ferric chloride;

the reaction is carried out under stirring at 120-180 rpm for 15-25 h;

the washing refers to solid-liquid separation by centrifugation, comprising washing solid with water; and

the ultrasonic conditions are an ultrasonic power of 120-180 W and an ultrasonic duration of 15-30 min.

7. A high-efficiency photothermal evaporative nano-particle porous membrane prepared with the method according to claim 1 .

8. The high-efficiency photothermal evaporative nano-particle porous membrane according to claim 7 , wherein the high-efficiency photothermal evaporative nano-particle porous membrane achieves a photothermal conversion efficiency of 88.56-93.79%, with a photothermal evaporation capacity of 1.33-1.41 kg·m −2 ·h −1 .

9. An application of the high-efficiency photothermal evaporative nano-particle porous membrane, comprising:

providing the high-efficiency photothermal evaporative nano-particle porous membrane according to claim 7 ; and

using the high-efficiency photothermal evaporative nano-particle porous membrane to desalinate seawater.