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Main observation and conclusion Photoredox C—H bond formation can proceed in aerobic environment under solar light and has therefore become attractive. Nowadays, different types of expensive novel metal complexes and nanomaterials have been urbanized as photocatalysts for direct C—H bond formation in between derivatives of heteroarenes (HAs) and aryl diazonium salts. These photocatalysts, however, still suffer from poor stability, high cost, and decay. Herein, a graphitic carbon nitride‐based fluorescein isothiocyanate (g‐C3N4–FITC) film photocatalyst has been reported, which shows excellent light harvesting ability, and band gap suitability to catalyze the metal free direct C—H arylation of HAs under solar light at ambient temperature. Moreover, the g‐C3N4–FITC film photocatalyst can be reused four times without significant loss of activity, confirming the excellent photocatalytic stability. The current strategy to construct a g‐C3N4–FITC film photocatalyst for direct C—H arylation opens a new path towards replacing metal‐based catalysts in fine chemical synthesis.

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Due to the pharmaceutical, biological, physical, and chemical properties of fluorinated compounds and 1,4-NADH/NADPH, these species have attracted a lot of attention from researchers across the chemical society. Despite their crucial significance, present methods of regenerating cofactors (1,4-NADH/NADPH) as well as inserting fluorine into organic compounds suffer from ruthless drawbacks. Herein, we designed a highly efficient S-gC3N4@Fe2O3/LC photocatalyst, and its in situ generations were accomplished by calcinations of Fe2O3, melamine (M), thiophenol (T), and lignin carbon (LC). The Fe2O3 part performs similar to an additional light harvester, gifting utmost photo-generated electrons, whereas the carbon part bridges a “thoroughfare” to make easy electron transfer from Fe2O3 to S-gC3N4 (Schemes 1 and 2). Therefore, the newly designed S-gC3N4@Fe2O3/LC photocatalyst is more efficient for the generation and regeneration of the C­(sp3)–F bond and 1,4-NADH/NADPH due to its surface active sites and defects.

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Solar light active oxygenation reactions and coenzyme regenerations are play crucial role in the area of pharmaceutical industry. The highly selective and efficient synthesis of oxygen-containing molecules in an environmental friendly manner is challenging at both industrial and laboratory level. Here, we proposed a new synthetic approach for oxygenation reactions along with coenzyme regenerations using flexible-activated carbon cloth (FACC) oriented covalent (C) tetrakis(4-carboxyphenyl) porphyrin (P) and thiourea (T)-based framework (F), namely, CPTF@FACC photocatalyst. CPTF@FACC exhibits excellent solar light-harvesting ability, well-distinct photocatalytic centers, high molar extinction coefficient, excellent charge transport ability, and suitable optical band gap, which make the photocatalyst more efficient for oxygenation (sulfoxidation and epoxidation) reactions along with coenzyme regenerations. The oxygenation reactions were carried out in isopropyl alcohol via in situ production of hydrogen peroxide (H 2 O 2 ) under solar light using CPTF@FACC photocatalyst with high yields (~97%-98%). Finally, the CPTF@FACC photocatalyst also show a benchmark example in the coenzymes regeneration with high yields 81.1% and 73.1% for NADH and NADPH in 2 h, respectively.

Covalent triazine frameworks (CTFs), belonging to the super‐family of covalent organic frameworks, have attracted significant attention as a new type of photosensitizer due to the superb light‐harvesting ability and efficient charge transfer originating from the large surface area. However, the wide optical band gap in CTFs, which is larger than 3.0 eV, hinders the efficient light harvesting in the visible range. To overcome this limitation, we developed the new type CTFs photocatalyst based on the donor–acceptor conjugation scheme by using melamine (M) and 2,6‐diaminoanthraquinone (AQ) as monomeric units. The melamine‐2,6‐diaminoanthraquinone‐based covalent triazine frameworks (M‐AQ‐CTFs) photocatalyst shows the excellent light‐harvesting capacity with high molar extinction coefficient, and the suitable optical band gap involving the internal charge transfer character. Combination of M‐AQ‐CTFs and artificial photosynthetic system including the organometallic rhodium complex, acting as an electron mediator, exhibited the excellent photocatalytic efficiency for the regeneration of the nicotinamide cofactors such as NAD(P)H. In addition, this photocatalyst showed the high photocatalytic efficiency for the metal‐free aerobic oxidation of sulfide. This study demonstrates the high potential of CTFs photocatalyst with the donor–acceptor conjugated scheme can be actively used for artificial photosynthesis.