Thiophene

All chemicals with analytical grade were used without further purification and purchased from Sinopharm Chemical Reagent Co. Ltd. (Beijing China) as follows: (NH₄)₆Mo₇O₂₄·4H₂O (99%), HNO₃ (98%), AgNO₃ (98.9%), KI (≥ 99.0%), thiophene (99%), ethanol (≥ 99.7%), BaSO₄, isopropanol alcohol (IPA, ≥ 99.7%), ethylenediamine tetraacetic acid disodium salt (EDTA-2Na, 99%), and 1, 4-benzoquinone (BQ, 98%). Deionized water was used for all reactions, if no any special emphasis is given otherwise.

Silicotungstic acid hydrate (H₄SiW₁₂O₄₀), phosphomolybdic acid hydrate (H₃PMo₁₂O₄₀), phosphotungstic acid hydrate (H₃PW₁₂O₄₀), 1-methylimidazole, (3-chloropropyl) trimethoxysilane, n-octane, hydrochloric acid, 30 wt% hydrogen peroxide, thiophene (T) and toluene were provided by Sinopharm Chemical Reagent Co., Ltd. and were of analytical grade. Poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (P123), benzothiophene (BT), 4,6-dimethyldibenzothiophene (4,6-DMDBT) and dibenzothiophene (DBT) were obtained from Sigma-Aldrich. 1,3,5-trimethylbenzene (TMB) and ethyl silicate (TEOS) were purchased from Aladdin Chemistry. Ionic liquid [BMIM]BF₄ was synthesized according to a published procedure [39 (link),40 (link)].