A method for preparing photoactive perovskite materials. The method comprises the steps of: introducing a lead halide and a first solvent to a first vessel and contacting the lead halide with the first solvent to dissolve the lead halide to form a lead halide solution, introducing a Group 1 metal halide a second solvent into a second vessel and contacting the Group 1 metal halide with the second solvent to dissolve the Group 1 metal halide to form a Group 1 metal halide solution, and contacting the lead halide solution with the Group 1 metal halide solution to form a thin-film precursor ink. The method further comprises depositing the thin-film precursor ink onto a substrate, drying the thin-film precursor ink to form a thin film, annealing the thin film; and rinsing the thin film with a salt solution.

A method for preparing photoactive perovskite materials. The method comprises the steps of: introducing a lead halide and a first solvent to a first vessel and contacting the lead halide with the first solvent to dissolve the lead halide to form a lead halide solution, introducing a Group 1 metal halide a second solvent into a second vessel and contacting the Group 1 metal halide with the second solvent to dissolve the Group 1 metal halide to form a Group 1 metal halide solution, and contacting the lead halide solution with the Group 1 metal halide solution to form a thin-film precursor ink. The method further comprises depositing the thin-film precursor ink onto a substrate, drying the thin-film precursor ink to form a thin film, annealing the thin film; and rinsing the thin film with a salt solution.

The present disclosure provides azeotrope or azeotrope-like compositions including trifluoroiodomethane (CF.sub.3I) and hexafluoroacetone (HFA), and a method of forming an azeotrope or azeotrope-like composition comprising the step of combining hexafluoroacetone (HFA) and trifluoroiodomethane (CF.sub.3I) to form an azeotrope or azeotrope-like comprising hexafluoroacetone (HFA) and trifluoroiodomethane (CF.sub.3I) having a boiling point of about 29.84 C.0.30 C. at a pressure of about 14.40 psia0.30 psia.

A method for preparing photoactive perovskite materials. The method comprises the steps of: introducing a lead halide and a first solvent to a first vessel and contacting the lead halide with the first solvent to dissolve the lead halide to form a lead halide solution, introducing a Group 1 metal halide a second solvent into a second vessel and contacting the Group 1 metal halide with the second solvent to dissolve the Group 1 metal halide to form a Group 1 metal halide solution, and contacting the lead halide solution with the Group 1 metal halide solution to form a thin-film precursor ink. The method further comprises depositing the thin-film precursor ink onto a substrate, drying the thin-film precursor ink to form a thin film, annealing the thin film; and rinsing the thin film with a salt solution.

A method for preparing photoactive perovskite materials. The method comprises the steps of: introducing a lead halide and a first solvent to a first vessel and contacting the lead halide with the first solvent to dissolve the lead halide to form a lead halide solution, introducing a Group 1 metal halide a second solvent into a second vessel and contacting the Group 1 metal halide with the second solvent to dissolve the Group 1 metal halide to form a Group 1 metal halide solution, and contacting the lead halide solution with the Group 1 metal halide solution to form a thin-film precursor ink. The method further comprises depositing the thin-film precursor ink onto a substrate, drying the thin-film precursor ink to form a thin film, annealing the thin film; and rinsing the thin film with a salt solution.

A process for producing acetic acid while efficiently separating permanganate reducing compounds (PRC's) and methyl iodide is provided. PRC's are separated or removed from a mixed composition (3A) containing PRC's and methyl iodide by distilling the mixed composition in a distillation step (5) to form an overhead stream (5A), a side-cut stream (5B), and a lower stream (5C). In a distillation column of the distillation step (5), an extractant (e.g., water) extracting PRC's preferentially to methyl iodide is added to a concentration zone in which PRC's and methyl iodide are concentrated, and an extraction mixture falling from the concentration zone is withdrawn as the side-cut stream (5B).

A method for preparing photoactive perovskite materials. The method comprises the steps of: introducing a lead halide and a first solvent to a first vessel and contacting the lead halide with the first solvent to dissolve the lead halide to form a lead halide solution, introducing a Group 1 metal halide a second solvent into a second vessel and contacting the Group 1 metal halide with the second solvent to dissolve the Group 1 metal halide to form a Group 1 metal halide solution, and contacting the lead halide solution with the Group 1 metal halide solution to form a thin-film precursor ink. The method further comprises depositing the thin-film precursor ink onto a substrate, drying the thin-film precursor ink to form a thin film, annealing the thin film; and rinsing the thin film with a salt solution.

A method for preparing photoactive perovskite materials. The method comprises the steps of: introducing a lead halide and a first solvent to a first vessel and contacting the lead halide with the first solvent to dissolve the lead halide to form a lead halide solution, introducing a Group 1 metal halide a second solvent into a second vessel and contacting the Group 1 metal halide with the second solvent to dissolve the Group 1 metal halide to form a Group 1 metal halide solution, and contacting the lead halide solution with the Group 1 metal halide solution to form a thin-film precursor ink. The method further comprises depositing the thin-film precursor ink onto a substrate, drying the thin-film precursor ink to form a thin film, annealing the thin film; and rinsing the thin film with a salt solution.

A method for preparing photoactive perovskite materials. The method comprises the steps of: introducing a lead halide and a first solvent to a first vessel and contacting the lead halide with the first solvent to dissolve the lead halide to form a lead halide solution, introducing a Group 1 metal halide a second solvent into a second vessel and contacting the Group 1 metal halide with the second solvent to dissolve the Group 1 metal halide to form a Group 1 metal halide solution, and contacting the lead halide solution with the Group 1 metal halide solution to form a thin-film precursor ink. The method further comprises depositing the thin-film precursor ink onto a substrate, drying the thin-film precursor ink to form a thin film, annealing the thin film; and rinsing the thin film with a salt solution.

A method for preparing photoactive perovskite materials. The method comprises the steps of: introducing a lead halide and a first solvent to a first vessel and contacting the lead halide with the first solvent to dissolve the lead halide to form a lead halide solution, introducing a Group 1 metal halide a second solvent into a second vessel and contacting the Group 1 metal halide with the second solvent to dissolve the Group 1 metal halide to form a Group 1 metal halide solution, and contacting the lead halide solution with the Group 1 metal halide solution to form a thin-film precursor ink. The method further comprises depositing the thin-film precursor ink onto a substrate, drying the thin-film precursor ink to form a thin film, annealing the thin film; and rinsing the thin film with a salt solution.