Regulating reactive oxygen species balance at the WO₃/BN interface for selective photooxidation of methane to methanol

Abstract

Direct photocatalytic oxidation of methane to methanol under ambient pressure offers an attractive route for C₁ valorization, yet it remains challenged by the competing requirements of activating inert C−H bonds while preventing methanol overoxidation. Here, a WO₃/BN interface is reported that addresses this activity–selectivity trade-off by regulating the balance of reactive oxygen species. Interfacial coupling with BN promotes hole extraction from WO₃ and induces electron accumulation in the WO₃ domains, thereby preferentially enhancing ·OOH generation and increasing the ·OOH/·OH ratio. The elevated ·OOH/·OH ratio balances methane activation and methanol formation. Specifically, ·OOH radicals facilitate C−H bond activation in methane, whereas ·OH radicals react with the resulting *CH₃ intermediates to form methanol. The optimized WO₃/BN-1:1 catalyst achieves a CH₃OH production rate of 741.6 μmol/(g·h), nearly twice that of pristine WO₃, with a CH₃OH selectivity of 77.2% under ambient-pressure conditions. This work provides insights into regulating reactive oxygen species through interface engineering for the selective photocatalytic conversion of methane.

Graphical abstract

Keywords

photocatalytic methane oxidation / selective methanol production / WO₃/BN interface / reactive oxygen species

References

[1] You J K , Bao Y F , Zhang Y Z . et al. Green energy driven methane conversion under mild conditions. EES Catalysis, 2024, 2(6): 1210–1227

[2] Wang Y F , Qi M Y , Tan C L . et al. Methane functionalization in heterogeneous photocatalysis. Materials Horizons, 2026, 13(10): 4803–4818

[3] Qiu J , Cao Y H , Tuo C M . et al. Sustainable conversion of natural gas to high-value chemicals. Gas Science and Engineering, 2026, 150: 205888

[4] Guo H T J , Cai J Y , Li K . et al. Water poisoning mechanisms and water resistance enhancement strategies in low-temperature thermal catalytic oxidation of methane.. Materials Reports, 2026,, 40(4): 25020069

[5] Wang Y X , Zhang Y Y , Wang X Q . et al. Photothermal direct methane conversion to formaldehyde at the gas-solid interface under ambient pressure. Nature Communications, 2025, 16(1): 2550

[6] Xu Y S , Wu D X , Zhang Q H . et al. Regulating Au coverage for the direct oxidation of methane to methanol. Nature Communications, 2024, 15(1): 564

[7] Yang M K , Huang Z A , Zhou Y X . et al. Co-production of few-layer graphene and hydrogen from methane pyrolysis based on Cu and metal oxide-KCl molten medium.. Journal of Inorganic Materials, 2025, 40(5): 473–480

[8] Ye R P , Ma L X , Mao J N . et al. A Ce-CuZn catalyst with abundant Cu/Zn-O_V-Ce active sites for CO₂ hydrogenation to methanol. Nature Communications, 2024, 15(1): 2159

[9] Busse C , Freund H , Schwieger W . Periodic open cellular structures (POCS) as catalyst support for intensified heat transport in the partial oxidation of methanol to formaldehyde. Chemical Engineering Journal, 2024, 489: 151139

[10] Cao Y H , Huang Z A , Han C Q . et al. Product peroxidation inhibition in methane photooxidation into methanol. Advanced Science, 2024, 11(12): 2306891

[11] Han C Q , Cao Y H , Huang C . et al. Photocatalytic methane oxidation to methanol in promoting methane conversion rate and methanol selectivity.. Progress in Chemistry, 2024, 36(6): 867–877

[12] Han C Q , Cao Y H , Qiu J . et al. Promotion of highly selective photocatalytic conversion of methane into methanol by Ga–O bifunctional sites.. Chinese Science Bulletin, 2023, 68(33): 4544–4555

[13] Wang P , Shi R , Zhao J Q . et al. Photodriven methane conversion on transition metal oxide catalyst: Recent progress and prospects. Advanced Science, 2024, 11(8): 2305471

[14] Xu Y X , Chen E Q , Tang J W . Photocatalytic methane conversion to high-value chemicals. Carbon Future, 2024, 1(1): 9200004

[15] Li Y , Cao Y H , Han C Q . et al. Spatiotemporal photon distribution control on active sites enables bio-inspired methane-to-methanol conversion. Nature Communications, 2026, 17(1): 3357

[16] Feng C Y , Zuo S W , Hu M . et al. Optimizing the reaction pathway of methane photo-oxidation over single copper sites. Nature Communications, 2024, 15(1): 9088

[17] Fan Y Y , Jin X J , Guo Z Q . et al. Controlling photocatalytic methane conversion pathways: Challenges and future directions. ACS Central Science, 2026, 12(5): 568–585

[18] Xie J J , Jin R X , Li A . et al. Highly selective oxidation of methane to methanol at ambient conditions by titanium dioxide-supported iron species. Nature Catalysis, 2018, 1(11): 889–896

[19] Luo L , Gong Z Y , Xu Y X . et al. Binary Au–Cu reaction sites decorated ZnO for selective methane oxidation to C1 oxygenates with Nearly 100% selectivity at room temperature. Journal of the American Chemical Society, 2022, 144(2): 740–750

[20] Xue F , Zhang C Y , Cheng C . et al. Selective light-driven methane oxidation to ethanol. Nature Communications, 2024, 15(1): 10451

[21] Liu Z H , Mao L , Liu Z Y . et al. Ethanol synthesis by CO₂ photoreduction catalyzed by self-optimized Ti^δ+-based heterojunction. Angewandte Chemie International Edition, 2026, 65(2): e22838

[22] Liu Z Y , Mao L , Liu Y F . et al. Ethanol photosynthesis from CO₂ and H₂O via a formate intermediate pathway. Nature Communications, 2026, 17(1): 4479

[23] Cao Y H , Guo R , Ma M Z . et al. Effects of electron density variation of active sites in CO₂ activation and photoreduction: A review. Acta Physico-Chimica Sinica, 2024, 40(1): 2303029

[24] Fan Y Y , Jiang Y H , Lin H T . et al. Insight into selectivity of photocatalytic methane oxidation to formaldehyde on tungsten trioxide. Nature Communications, 2024, 15(1): 4679

[25] Xu A , Zhang Y K , Fan H G . et al. WO₃ nanosheet/ZnIn₂S₄ S-scheme heterojunctions for enhanced CO₂ photoreduction. ACS Applied Nano Materials, 2024, 7(3): 3488–3498

[26] Wang K R , Luo L , Wang C . et al. Photocatalytic methane activation by dual reaction sites co-modified WO₃. Chinese Journal of Catalysis, 2023, 46: 103–112

[27] Cao Y H , Yu W , Han C Q . et al. Methane photooxidation with nearly 100% selectivity towards oxygenates: Proton rebound ensures the regeneration of methanol. Angewandte Chemie International Edition, 2023, 62(18): e202302196

[28] Cao Y H , Yu W , Li Y . et al. Engineering ultrafast photo-induced charge and carbon intermediates transfer at interface to break the activity–selectivity trade-off in direct conversion of methane to methanol. Advanced Energy Materials, 2025, 15(6): 2404871

[29] Chen F , Wang J M , He Y . et al. Regulating reactive oxygen species with H₂ over PdCu/ZnO for selective photocatalytic aerobic oxidation of methane to methanol. ACS Catalysis, 2026, 16(7): 6699–6707

[30] Qiu S S , Liu X X , Liang J C . et al. Dual active sites decorated tungsten trioxide for photocatalytic methane oxidation. Advanced Energy Materials, 2025, 15(28): 2406119

[31] Biswas A , Xu R , Christiansen-Salameh J . et al. Phase stability of hexagonal/cubic boron nitride nanocomposites. Nano Letters, 2023, 23(15): 6927–6936

[32] He Y , Yu W , Cao Y H . et al. Fe-enhanced proton capture on boron nitride surfaces for improved photocatalytic methane conversion to C1 chemicals. Small Science, 2026, 6(5): e70302

[33] Zhou M , Du X Y , Thiruppathiraja T . et al. Insight into self-dissociation of poly(heptazine imide) nanosheets enables boosted CO₂ photoreduction. AIChE Journal, 2025, 71(7): e18850

[34] Cao Y H , Zhang R Y , Zhou T L . et al. B–O bonds in ultrathin boron nitride nanosheets to promote photocatalytic carbon dioxide conversion. ACS Applied Materials & Interfaces, 2020, 12(8): 9935–9943

[35] Yu W , Yang Y T , Cao Y H . et al. In situ H-bond-mediated intermediate stabilization on Ga₂O₃/BN for highly selective photocatalytic methane oxidation to methanol. Applied Catalysis B: Environment and Energy, 2026, 385: 126333

[36] Lee J , Kim S Y , Yoo H S . et al. Pd-WO₃ chemiresistive sensor with reinforced self-assembly for hydrogen detection at room temperature. Sensors and Actuators B: Chemical, 2022, 368: 132236

[37] Vasilopoulou M , Soultati A , Georgiadou D G . et al. Hydrogenated under-stoichiometric tungsten oxide anode interlayers for efficient and stable organic photovoltaics. Journal of Materials Chemistry A, 2014, 2(6): 1738–1749

[38] Zeng Y , Tang Z Y , Wu X Y . et al. Photocatalytic oxidation of methane to methanol by tungsten trioxide-supported atomic gold at room temperature. Applied Catalysis B: Environmental, 2022, 306: 120919

[39] Wu X Y , Zhang Q , Li W F . et al. Atomic-scale Pd on 2D titania sheets for selective oxidation of methane to methanol. ACS Catalysis, 2021, 11(22): 14038–14046

[40] Song H , Meng X G , Wang S Y . et al. Direct and selective photocatalytic oxidation of CH₄ to oxygenates with O₂ on cocatalysts/ZnO at room temperature in water. Journal of the American Chemical Society, 2019, 141(51): 20507–20515

[41] Feng N D , Lin H W , Song H . et al. Efficient and selective photocatalytic CH₄ conversion to CH₃OH with O₂ by controlling overoxidation on TiO₂. Nature Communications, 2021, 12(1): 4652

[42] Zhou W C , Qiu X Y , Jiang Y H . et al. Highly selective aerobic oxidation of methane to methanol over gold decorated zinc oxide via photocatalysis. Journal of Materials Chemistry A, 2020, 8(26): 13277–13284

[43] Zhang Z J , Zhang J , Zhu Y R . et al. Photo-splitting of water toward hydrogen production and active oxygen species for methane activation to methanol on Co-SrTiO₃. Chem Catalysis, 2022, 2(6): 1440–1449

[44] Luo L H , Luo J , Li H L . et al. Water enables mild oxidation of methane to methanol on gold single-atom catalysts. Nature Communications, 2021, 12(1): 1218

[45] Yu W , Zhang X , Cao Y H . et al. Ultrafast interfacial charge-delivery gating enables radical-suppressed photocatalytic methane-to-C₁ oxygenates. Applied Catalysis B: Environment and Energy, 2026, 394: 126819

[46] . , ,

[47] Zhang X M , Jiang Y H , Gu H F . et al. Near-infrared photon-triggered CH₄-to-CH₃OH conversion over plasmonic oxyselenides. Nature Communications, 2025, 16(1): 7612

[48] Luo L , Han X Y , Wang K R . et al. Nearly 100% selective and visible-light-driven methane conversion to formaldehyde via. single-atom Cu and W^δ+. Nature Communications, 2023, 14(1): 2690

[49] Liu D D , Chen F , He Y . et al. Intensifying internal electric field on ZnO nanoplates with polar surface exposure and Cu doping for efficient photocatalytic methane oxidation to oxygenates. Advanced Functional Materials, 2026, 36(18): e20271

[50] Chen F , Zhou H Y , Liu D D . et al. Defective ZnO nanoplates supported AuPd nanoparticles for efficient photocatalytic methane oxidation to oxygenates. Advanced Energy Materials, 2024, 14(11): 2303642

[51] Zhou H Y , Chen F , Liu D D . et al. Boosting reactive oxygen species formation over Pd and VO_δ co-modified TiO₂ for methane oxidation into valuable oxygenates. Small, 2024, 20(29): 2311355

[52] Chen X X , Li Y P , Pan X Y . et al. Photocatalytic oxidation of methane over silver decorated zinc oxide nanocatalysts. Nature Communications, 2016, 7: 12273

[53] Li W L , Ma R , Liu Z Y . et al. Boosting CO₂ photoreduction by creating electron mediator in carbon-enriched poly(heptazine imide). AIChE Journal, 2025, 71(6): e18782

[54] He Y , Sheng J P , Ren Q . et al. Metastable dual-defect states drive deep protonation for selective CO₂ photomethanation. Nature Communications, 2025, 16(1): 10722

[55] Yang H K , Zhang Z N , Guo Y D . et al. Concurrent photocatalytic CO₂ reduction and 1-phenylethanol oxidation regulated by chloride ion-capped CdS@Zn_xCd_1–xS@ZnS QDs. Advanced Functional Materials, 2025, 35(31): 2502562

[56] Shaaban E , Li G H . Probing active sites for carbon oxides hydrogenation on Cu/TiO₂ using infrared spectroscopy. Communications Chemistry, 2022, 5(1): 32

[57] Wu T H , Lin D M , Wu Y . et al. In-situ FT-IR investigation of partial oxidation of methane to syngas over Rh/SiO₂ catalyst. Journal of Natural Gas Chemistry, 2007, 16(3): 316–321

[58] Wheeler O W , Salem M , Gao A . et al. Activation of C–H bonds in Pt⁺ + x CH₄ reactions, where x = 1–4: Identification of the platinum dimethyl cation. The Journal of Physical Chemistry A, 2016, 120(31): 6216–6227

[59] Kattel S , Yan B H , Yang Y X . et al. Optimizing binding energies of key intermediates for CO₂ hydrogenation to methanol over oxide-supported copper. Journal of the American Chemical Society, 2016, 138(38): 12440–12450

[60] Mao J , Liu H , Cui X J . et al. Direct conversion of methane with O₂ at room temperature over edge-rich MoS₂. Nature Catalysis, 2023, 6(11): 1052–1061

[61] Han C Q , Cao Y H , Yu W . et al. Selective cleavage of chemical bonds in targeted intermediates for highly selective photooxidation of methane to methanol. Journal of the American Chemical Society, 2023, 145(15): 8609–8620

[62] Li H Y , Pei W , Yang X W . et al. Pt overlayer for direct oxidation of CH₄ to CH₃OH. Chinese Chemical Letters, 2023, 34(11): 108292

Rights & permissions

Higher Education Press