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[Display omitted] • A considerable productivity and selectivity of methanol (180.75 μmol·g cat −1·h−1, 80.07 %) are achieved. • Cl− could be transformed into Cl over BiOCl-O v to efficiently activate methane. • The in situ produced Cl is constrained on the surface of BiOCl-O v , inhibiting over halogenation. • Reactive oxygen species produced by H 2 O 2 dissociation are utilized to be the receptors of CH 3. Selective partial oxidation of methane to methanol under mild conditions remains a great challenge in activating the first C H bond of CH 4 and inhibiting overoxidation. Chlorine-mediated pathway arises as a promising strategy to obtain high CH 4 conversion under mild conditions. Herein, a considerable CH 3 OH production rate of 180.75 μmol·g cat −1·h−1 with 80.07 % selectivity is achieved when the BiOCl with oxygen vacancies is irradiated by visible light in NaCl solution with H 2 O 2 addition. Experimental studies reveal that chlorine radicals are in situ produced and constrained on the surface of the catalyst, which inhibits the over halogenation. Reactive oxygen species produced by H 2 O 2 dissociation were utilized to be the receptors of CH 3. The high productivity of methanol was achieved by the synergy effect of chlorine radicals and H 2 O 2. This work provides a new feasible method to convert inert methane into high-value-added products via photocatalysis. [ABSTRACT FROM AUTHOR]

• Lewis acidic and Brønsted acidic sites are assembled in the Co-MoO x /PW catalyst. • The photo-thermal bifunctional Co-MoO x /PW catalyst induced remarkable catalytic performance for conversion of LA to GVL. • A mild and low-cost route based on photothermal effect was expected for the biomass upgrade. Efficient synthesis of γ-valerolactone (GVL) has attracted wide attention due to its extensive applications as a promising fuel additive. Herein, we report a new path to obtain GVL by intermolecular hydrogen transfer from isopropanol to levulinic acid (LA) upon the Co-MoO x /polyoxometallic hybrid catalysts even without exogenous H 2 atmosphere. This conversion could proceed efficiently not only based on thermal catalysis, but also on photocatalysis due to its photo-thermal property. Moreover, the control experiments reveal that phosphotungustic acid (HPW) worked as acid sites for esterification and dealcoholization reaction. The doped Co species as Lewis acidic sites catalyze the formation of GVL from LA as well as affect the hydrogenation activity of MoO x. This work provides a photo-thermal catalyst for upgrading biomass-derived compounds under mild condition. [Display omitted] [ABSTRACT FROM AUTHOR]

One-step photocatalytic methane conversion to acetic acid possesses high economic and academic value, and carbonyl species (CO, CO 2) are usually necessary to be introduced into the reaction system to realize the carbon-carbon coupling reaction, which requires high energy input. In this work, a composite photocatalyst (Ag/AgCl-WO 3-x) was constructed to successfully realize the one-step photocatalytic conversion of CH 4 to CH 3 COOH without addition of carbonyl species. Chlorine radicals and hydroxyl radicals could be produced simultaneously under light irradiation over Ag/AgCl. Specifically, CH 4 could undergo the hydrogen atom transfer reaction with chlorine radicals to produce methyl species, and hydroxyl radicals could mineralize CH 4 to produce carbonyl species. After further combining WO 3 − x , carbon-carbon coupling reaction between carbonyl and methyl species occurred to effectively produce CH 3 COOH (188.5 μmol·g cat −1·h−1). This work provides a new prospect of designing photocatalytic system to realize CH 4 conversion to C 2 products. [Display omitted] • One-step conversion of CH 4 to CH 3 COOH is achieved over the photocatalyst of Ag/AgCl-WO 3−x. • ·Cl and ·OH produced over Ag/AgCl contributed to obtain active methyl and carbonyl species, respectively. • WO 3−x enables the C-C coupling reaction between methyl and carbonyl species. [ABSTRACT FROM AUTHOR]