Titanium diisopropoxide bis acetylacetonate

Fluorine-doped tin oxide (FTO) glass (TEC-A7, Pilkington) was washed in ethanol under ultrasonication for 20 min, followed by treatment with UV/O₃ (Yuil Ultraviolet System) for 15 min to remove any contaminants. Titanium diisopropoxide-bis(acetylacetonate) (7.5 wt%, Aldrich) in n-butanol was spin-coated on the surface of the washed FTO glass and subsequently annealed at 475 °C for 10 min in air. A nanocrystalline TiO₂ paste (Ti-Nanoxide T/SP, Solaronix) was coated on the pretreated FTO glass using the doctor-blade method, followed by annealing at 525 °C for 30 min in air. Finally, the annealed FTO/mesoporous TiO₂ film was immersed in a colloidal CISe QD solution (4.0 mg/mL) for 3 h for sensitization and then rinsed with dichloromethane. The ZnS overlayers were coated on the surface of the QD-sensitized TiO₂ film by successive ionic layer adsorption and reaction (SILAR) processes, consisting of immersing the QD-sensitized TiO₂ film in a 0.05 M Zn(NO₃)₂·6H₂O ethanol solution and 0.05 M Na₂S in a mixed solvent of deionized water/methanol (volume ratio = 1:1) for 1 min each. The SILAR process was repeated thrice.

Dichloromethane (DCM, 99.8%, Chem-Supply), tetrabutylammonium perchlorate (TBAP, 99.0%, Fluka), ferrocene (Fc, 98%, Aldrich), titanium diisopropoxide bis(acetylacetonate) (TAA, 75% in isopropanol, Aldrich), ethanol (99.8%, Sigma-Aldrich), TiO₂ paste (18-NRT, Dyesol), titanium IV chloride (TiCl₄, 99.0%, Sigma-Aldrich), tetrahydrofuran (THF, 97%, Ajax), 1,2-dimethyl-3-propylimidazolium iodide (DMPII, synthesized in house), lithium iodide (LiI, 99.9%, Aldrich), I₂ (99.99%, Aldrich), tert-butylpyridine (tBP, 96%, Aldrich), acetonitrile (AN, 99.8%, Sigma-Aldrich), valeronitrile (VN, 99.5%, Sigma-Aldrich), tris(2,2′-bispyridine)cobalt II/III (Co²⁺/Co³⁺, synthesized in house), chenodeoxycholic acid (CDCA, Solaronix), fluorine doped tin oxide glass (FTO glass, 2.2 mm, 7 Ω □^–1, TEC®), glass microscope slides (Sail brand, 1 mm thick).
Por–(Cb-TPA), Cb-TPA and Por were synthesized as described in ref. 10 .

The fluorine doped tin oxide (FTO) substrate was etched with Zn dust and 2 M hydrochloric acid and cleaned with acetone and 2-propanol for 10 min respectively. The FTO substrate was dried with nitrogen and exposed to oxygen plasma treatment. To creat the TiO₂ compact layer (CP-TiO₂), 0.10 M titanium diisopropoxide bis (acetylacetonate) (Sigma-Aldrich, 75 wt%, in IPA, Signa-Aldrich) solution was deposited on the FTO substrate and annealed at 450 °C for 30 min. The PANI solution was then coated onto the CP-TiO₂ layer. A mixture solution of 1.0 M PbI₂ (1.0 M, Sigma-Aldrich) and 1.0 M CH₃NH₃I in N,N-Dimethylformamide (DMF), and dimethylsulfoxide (DMSO) at a ratio of 4:1 (v:v), was coated on the PPL and dried at 100 °C for 10 min. A Spiro-MeOTAD containing [28.8 μL of Spiro-MeOTAD (Lumtec) (72.3 mg/mL in chlorobenzene), 4-tert-butylpyridine (Sigma-Aldrich, 96% The TSFI stock solution (Sigma-Aldrich, 99.8%) was stirred for 24 h)] was coated on the MAPbI₃ layer. A gold electrode was created using thermal evaporation equipment.

FTO-patterned glass substrates were purchased from Asahi glass (Tokyo, Japan). Lead iodide (PbI₂), methylammonium bromide (MABr), lead bromide (PbBr₂), formamidinium iodide (FAI), and cesium iodide (CsI) were purchased from Tokyo Chemical Industry (Tokyo, Japan). The N,N-dimethylformamide (DMF; 99.5% purity) and dimethyl sulfoxide (DMSO; 99.5% purity) were purchased from Wako Pure Chemical (Osaka, Japan). Titanium diisopropoxide bis(acetylacetonate) (75 wt% in isopropanol) and 2-isopropanol (99.9% purity) were supplied from Sigma-Aldrich, Wako Pure Chemical, respectively.

Corn starch (CNS), potassium iodide (KI), polyvinylidene fluoride (PVDF), and acetone were purchased from Hi-Media, India; the ionic liquid (IL), 1-ethyl-3-methylimidazolium thiocyanate (EmImSCN), was purchased from TCI Chemical India Private Limited, India; fluorine-doped tin oxide (FTO), titania paste, N₇ dye, and titanium diisopropoxide bis(acetylacetonate) were purchased from Sigma Aldrich, India; graphite sheets were purchase from Nikunj Pvt. Ltd. Mumbai, India; DD water was produced within the laboratory using a distillation unit.

Zinc 5,10,15,20-tetrapyridylporphyrin (ZnTPyP) was purchased from J&K Scientific LTD. 4% Paraformaldehyde was purchased from Beyotime. MPTP (1-methyl-4-fenyl-1,2,3,6-tetrahydropyridin) (Adamas life, Y39211C) was purchased from Adamas Life. Sodium dodecyl sulfate (SDS), sodium hydroxide (NaOH), hydrochloric acid (HCl, 36%~38%), methanol, dimethyl sulfoxide (DMSO), acetonitrile and ethanol were purchased from Sinopharm Chemical Reagent Co., Ltd. (Beijing, China). 2.5% glutaraldehyde, Poly-l-lysine (PLL), 5,5-dimethyl-pyrroline-N-oxide (DMPO), 5,5’-Dithiobis-(2-nitrobenzoic acid) (DTNB), and titanium diisopropoxidebis (acetylacetonate) (TDAA), Glutathione, K-Gluconic acid, HEPES, Sodium Ascorbate, Thiourea, Sodium Pyruvate, N-acetyl-L-cysteine, MgSO₄·7H₂O, Glucose, Cs-Methanesulfonate, TEA-Cl, MgCl₂, EGTA, Mg-ATP and Na-GTP were purchased from Sigma-Aldrich. All reagents were of analytical grade and were used without further purification.