Lithium iodide

Nickel (II) nitrate hexahydrate (Ni(NO₃)₂ • 6H₂O), trioctylphosphine (TOP, 97%), titanium (IV) tetraisopropoxide (TTIP, >98%), 2-methoxyethanol (CH₃OCH₂CH₂OH, ≥99.5%), lithium perchlorate (LiClO₄, ≥98.0%), ethanol (EtOH, 99.5%) and isopropyl alcohol (IPA, 99.5%) were purchased from Sigma-Aldrich (St. Louis, MO, USA). Iodine (I₂, synthetic grade), lithium iodide (LiI, synthetic grade), and poly(ethylene glycol) (PEG, MW~20,000) were supplied by Merck (Rahway, NJ, USA). Acetone ( $\ge$ 99%), 4-tert-butylpyridine (tBP, 96%), and tert-butyl alcohol (tBA, 96%) were acquired from Acros, and 3-methoxypropionitrile (MPN, 99%) was bought from Fluka (Buchs, Switzerland). Transparent titanium dioxide (TiO₂) paste (TL paste, Ti-nanoxide HT/SP, 13 nm), cis-diisothiocyanato-bis(2,2′-bipyridyl-4,4′-dicarboxylato) ruthenium (II) bis(tetrabutylammonium) (N719 dye), and 1,2-dimethyl-3-propylimidazolium iodide (DMPII) were obtained from Solaronix (S.A., Aubonne, Switzerland). Commercial light-scattering TiO₂ particles (ST-41 with 200 nm) were procured from Ishihara Sangyo, Ltd. (Nishi-ku, Osaka, Japan). Nitric acid (HNO₃, 65% solution in water), acetonitrile (ACN, 99.99%) was received from J. T. Baker. Polyester tape (1350F-1, 63 μm) was from the 3M Company (St. Paul, MN, USA).

All reactants employed in this research were provided in high-grade quality. Mercury(ii) acetate (Hg(OAc)₂), lithium iodide (LiI·2H₂O), thallium(i) nitrate (TlNO₃), polyvinyl pyrrolidone (PVP-25000), sodium salicylate (NaHSal), sodium dodecyl sulfate (SDS), ethylenediaminetetraacetic acid were purchased from Merck and utilized with no more refinement. The XRD of products was recorded by a Rigaku D-max CIII XRD using Ni-filtered Cu Kα radiation. SEM images were obtained on Philips XL-30ESEM, equipped with energy-dispersive X-ray spectroscopy. The EDS analysis with 20 kV accelerated voltage was done. An MPI Ultrasonic with the power of 1000 W, 20 kHz, from Switzerland (multi-wave ultrasound generator) by a transducer/converter was provided. A titanium oscillator was utilized for ultrasound radiation. The mixtures temperature vs. time was recorded for measuring the output power. This process was done in our previous work.^{14,19 (link)} The dT/dt evaluated plans from temperature (T) vs. time (t) data. Then the power of ultrasonic can estimate as follow: which M is the mass of water (solvent, kg), and c_p is the heat capacity of water (J kg⁻¹ K⁻¹). The calculated value from output power was estimated at 16.2 W, in the di-ionized water (for the input power of about 60 W).

n-Type silicon wafers (CZ, 1–10 Ω
cm) were purchased from Siegert Wafer GmbH, Germany. Fluorine-doped
tin oxide (FTO) with a sheet resistance of ∼25 Ω cm² was purchased from Pilkington. Antimony chloride (SbCl₃), zinc (Zn) dust, copper nitrate trihydrate (Cu(NO₃)₂·3H₂O), silver nitrate (AgNO₃), nickel nitrate hexahydrate (Ni(NO₃)₂·6H₂O), hexamethylenetetramine or hexamine (C₆H₁₂N₄), lithium iodide (LiI), iodine (I₂), poly(ethylene oxide) (PEO, MW: 600 000), N-[3-(trimethoxysilyl)propyl]aniline
(TMSPA), 3-propyl-1-methyl imidazolium iodide (PMII), 1-ethyl-3-methyl
imidazolium thiocyanate (EMISCN), hydrofluoric acid (HF, 40%), ammonia
(NH₃, 32%), hydrogen peroxide (H₂O₂, 30%), toluene (C₇H₈), formic acid (H₂CO₂, 95%), hydrochloric acid (HCl, 37%), sulfuric
acid (H₂SO₄, 98%), ethanol, acetone, and isopropanol
were purchased from Merck. Ultrapure water with a resistivity of ∼18.2
MΩ cm was obtained from the Millipore Direct-Q3 UV system.