Methods of making highly stable perovskite-polymer composites and structures using same
Methods of making luminescent perovskite-polymer composites are provided and structures using the same. Perovskite-polymer composites made by the method described herein are provided. The perovskite-polymer composite is useful in many applications including downconverters for backlight units (BLU) of liquid crystal displays (LCDs), as well as for and could be used for light emitting devices, lasers or as active absorber or passive luminescent concentrators for solar photovoltaic applications.
1. A method of making a perovskite-polymer composite, the method comprising,
(i) contacting a perovskite precursor solution, comprising perovskite precursors, with a substrate, comprising a polymer matrix in the presence of a solvent; and
(ii) creating a solvent-induced polymer swelling-deswelling process wherein the solvent penetrates the polymer matrix causing swelling of the polymer matrix and entry of the perovskite precursors into the polymer matrix; and
(iii) removing the solvent from the polymer matrix leaving the perovskite precursors in the polymer matrix to react and to form perovskite nanocrystals;
wherein the polymer matrix deswells forming a barrier layer around the perovskite nanocrystals to create the perovskite-polymer composite.
2. The method of claim 1 , wherein the perovskite precursor solution comprises PbX 2 and RNH 3 X to yield RNH 3 PbX 3 in solvent,
wherein R is an unsubstituted or substituted C 1 -C 20 alkyl or inorganic group, and
wherein X is one or more different halide anions selected from the group consisting of fluoride (F − ), chloride (Cl − ), bromide (Br − ), and iodide (I − ).
3. The method of claim 1 , wherein the perovskite precursor solution is an inorganic solution comprising PbX 2 and CsX to yield CsPbX 3 in solvent,
wherein R is an unsubstituted or substituted C 1 -C 20 alkyl or inorganic group, and
wherein X is one or more different halide anions selected from the group consisting of fluoride (F − ), chloride (Cl − ), bromide (Br − ), and iodide (I − ).
4. The method of claim 1 , wherein the perovskite precursor solution is processed from a process selected from the group consisting of spin coating, dip coating, slot die coating, ink jet coating, spray coating and cotton swab painting.
5. The method of claim 1 , wherein the solvent is selected from the group consisting of dimethylformamide (DMF), dimethyl sulfoxide (DMSO), r-butyrolactone (GBL), acetone, and acetonitrile.
6. The method of claim 1 , wherein the solvent is removed by baking at 25-120 degrees Celsius.
7. The method of claim 1 , wherein the polymer matrix comprises one or a combination selected from the group consisting of polystyrene (PS), polycarbonate (PC), cellulose acetate (CA), polyvinal chloride (PVC), poly (vinylidene fluoride), (PVDF), polyurea (PU), poly (methyl methacrylate) (PMMA), polyvinyl alcohol (PVA), and polynitriles.