Ethanol

HPLC solvents including methanol (≥ 99.9%), water (≥ 100%), and acetonitrile (≥ 99.9%) were purchased from J.T. Baker (Phillipsburg, NJ, USA). Folin-Ciocalteu reagent, gallic acid (3,4,5-trihydroxybenzoic acid, ≥ 99%), kaempferol (≥ 97%), quercetin (≥ 95%), DPPH (≥ 100%), ABTS^·+ (≥ 100%), trolox (≥ 97%) were purchased from Sigma-Aldrich (St. Louis, MO, USA). methanol (≥ 99%; Duksan, Gyeonggi-do, Korea), Na₂CO₃ (≥ 99.9%; Duksan), ethanol (≥ 99.9%; Samchun, Pyeongtaek, Gyeonggi-do, Korea), aluminum chloride (98%; Junsei, Japan), and potassium acetate (≥ 99%; Duksan) were also used.

SnCl₂ dihydrate, TGA, urea, Zn powder, detergent for an ultrasonic cleaner, MACl, dimethylformamide (DMF), dimethyl sulfoxide (DMSO), oleylamine, octane, chloroform (CF), Bis(trifluoromethane)sulfonimide lithium salt (Li-TFSI), 4-tert-butylpyridine (tBP), acetonitrile (AN), and chlorobenzene (CB) were purchased from Sigma-Aldrich. FAI (FA: formamidinium), MABr (MA: methylammonium), and OAI were purchased from Greatcell Solar. PbI₂ and PbBr₂ were purchased from TCI. spiro-OMeTAD and tris(2-(1H-pyrazol-1-yl)-4-tert-butylpyridine)cobalt(III)tris(bis(trifluoromethylsulfonyl)imide)) (FK209) were purchased from LumTec. HCl, ethanol, acetone, and isopropyl alcohol (IPA) were purchased from Samchun. Ethyl ether was purchased from Duksan. Fused silica substrates were purchased from Hanjin Quartz. Fluorine-doped tin oxide (FTO) substrates were purchased from Asahi. Au was purchased from iTASCO. All chemicals were used as received without further purification.

MoS₂ powder was purchased from Sigma-Aldrich (Merck, Darmstadt, Germany). NMP, N,N-dimethylformamide, hydrochloric acid (HCl), dimethyl sulfoxide, and ethanol were purchased from Samchun Chemical, Inc (Seoul, Republic of Korea). Isopropyl alcohol and hydrazine monohydrate were purchased from JUNSEI (Tokyo, Japan). All chemicals were used without further purification.

The rigid section paste was prepared by mixing 3.0 g of polydimethylsiloxane (PDMS, 10:1 mixture of a prepolymer: curing agent, Sylgard 184, Dow Corning, Midland, MI, USA), 4.5 g of glass fiber (GF) (milled fiber glass 50 um, Fiberman, Burnaby, BC, Canada), and 0.3 g of hexane (Daejung Chemicals & Materials Co., Siheung-si, Gyeonggi-do, Korea) using a Thinky Mixer (ARE-310, Japan) for 3 min, deformed for 1 min, and then mixed for 1 min. The intermediate section paste was prepared by mixing high-viscosity PDMS (10:1 mixture of a prepolymer:curing agent, Sylgard 186, Dow Corning) using a Thinky Mixer for 3 min, deformed for 1 min, and then mixed for 1 min. The soft section solution was prepared by mixing PDMS (20:1, Sylgard 184) and a reverse-micelle-induced (RMI) solution. First, a solution for the aqueous core of the RMI was prepared by stirring 1.0 mL of ethanol (95%, Samchun Chemical) and 0.1 g of 5-amino-1-pentanol (95%, Sigma-Aldrich, St. Louis, MO, USA) [22 (link)]. Then, 0.1 mL of the solution was mixed with 5.0 mL of octane (95%, Samchun Chemical Co., Seoul, Korea) and 1.0 mL of 1-octanol (99%, Sigma-Aldrich). Finally, 1.5 mL of the RMI solution was mixed with 10.0 g of PDMS (20:1, Sylgard 184).

MBN was synthesized using a modified sol-gel process. Briefly, 3.12 g calcium nitrate tetrahydrate (Ca(NO₃)₂·4H₂O) (Sigma-Aldrich, St. Louis, MO, USA), 2 mL aqueous ammonia (Samchun, Seoul, Korea), 10 mL 2-ethoxyethanol (Sigma-Aldrich, St. Louis, MO, USA), 20 mL ethanol (Samchun, Seoul, Korea), and 1 g hexadecyltrimethylammonium bromide (CTAB) (Sigma-Aldrich, St. Louis, MO, USA) were mixed in 150 mL distilled water. The mixture was stirred at room temperature for 30 min. Then, 5 mL tetraethyl orthosilicate (TEOS; Sigma-Aldrich, St. Louis, MO, USA) was added and stirred at room temperature for 30 min. Subsequently, 0.25 mL triethyl phosphate (TEP; Sigma-Aldrich, St. Louis, MO, USA) was added and the mixture was vigorously stirred for 4 h at room temperature. A white precipitate was formed and dried in a vacuum oven at 60 °C for 24 h. The dried gel powder was calcined at 600 °C for 5 h. The molar ratio of SiO₂:CaO:P₂O₄ was calculated to be 60:36:4.