Anaerobic photocatalytic dihydroxylation of propylene to propylene glycol and hydrogen at ambient temperature and pressure

doi:10.1016/S1872-2067(26)65228-X

Abstract

Abstract:

The oxidant-free dihydroxylation process of olefin using water as hydroxyl source represents a highly desirable strategy for synthesizing diols as it reduces the risk of over-oxidation of the olefin and enhances the safety of the production process, however, remaining to be a challenge under mild reaction conditions. Herein, we demonstrate a photocatalytic non-oxidative dihydroxylation pathway that only can utilize sunlight, propylene, and water to directly produce 1,2-propylene glycol (1,2-PG) and hydrogen over a silver nanoparticle-loaded TiO₂ (Ag-TiO₂) under ambient pressure and temperature. In-situ spectroscopic analyses combining with density functional theory simulations revealed that only Ag nanoparticles can capture photogenerated holes from TiO₂ instead of electrons, enabling the rate-determining hydroxylation step with a lower energy barrier (0.33 eV) at the Ag-TiO₂ interface compared to other noble metal-TiO₂ interfaces. A 1,2-PG yield of 177.7 μmol g^-1 h^-1 was achieved on Ag-TiO₂ via photocatalytic non-oxidative dihydroxylation pathway under ambient conditions. In contrast, only a trace amount of 1,2-PG was detected on other noble metal-loaded catalysts. More importantly, Ag-TiO₂ could consistently produce 1,2-PG (168.4 μmol g^-1) and hydrogen without any decline in activity under natural sunlight irradiation. This work establishes an integrated photocatalytic route for non-oxidative dihydroxylation process of olefin coupled with hydrogen production, offering a green and scalable pathway for solar-driven olefin functionalization.

Key words: Anaerobic dihydroxylation, Hydrogen generation, Ambient condition, Photocatalysis, Propylene

Xinyu Song, Wei Wang, Xiaomin Lao, Yitong Liu, Huanmin Liu, Peng Zhou. Anaerobic photocatalytic dihydroxylation of propylene to propylene glycol and hydrogen at ambient temperature and pressure[J]. Chinese Journal of Catalysis, 2027, 92: 115-122.

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URL: https://www.cjcatal.com/EN/10.1016/S1872-2067(26)65228-X

https://www.cjcatal.com/EN/Y2027/V92/I1/115

Figures/Tables 4

Scheme 1. Illustration of different reaction processes to synthesize glycols from olefins, and their main advantages and disadvantages are compared.

Fig. 1. (a) Comparative Gibbs free energy profiles for the dihydroxylation of C3H6 over different metal-TiO2 catalysts. Stick models represent the TiO2 substrate with supported metal nanoparticles (color code: gray, C; light yellow, O; light purple, H). Configuration of the reaction species during the hydroxylation of C3H6 over Ag-TiO2. OH*, Pr*, PrOH* and PG* represent surface hydroxyl group, adsorbed propylene, the hydroxypropyl intermediate (C3H6OH*), and the final product 1,2-PG. (b) Comparison of the density of states (DOS) for various metal clusters supported on TiO2. (c) Linear correlation between the d-band center of different metal-TiO2 catalysts and the reaction energy barrier of the rate-determining step.

Fig. 2. (a) AC-HAADF-STEM image of Ag-TiO2 and corresponding particle size distribution of Ag nanoparticles. (b) The FFT and IFFT processing diagrams of Ag nanoparticles, along with corresponding metal lattice diagrams. (c) The elemental distribution analysis conducted through HRTEM, along with its complementary EDS elemental mapping of Ag-TiO2. (d) Comparison of liquid-phase products from C3H6 photocatalytic conversion over different catalysts. Reaction conditions: [catalyst] = 0.5 mg mL-1, T = 20 °C, p = atmospheric pressure, light intensity = 462 mW cm-2. (e) Effect of Ag loading amount on liquid product yields and total carbon selectivity toward 1,2-PG. (f) Time-dependent product selectivity in the photocatalytic propylene hydration over Ag-TiO2. (g) Reusability of the Ag-TiO2 photocatalyst over consecutive cycles. (h) Schematic illustration of the outdoor photocatalytic setup driven by natural sunlight. (i) Co-production yields of 1,2-PG and H2 during five consecutive days of outdoor solar experiments. Experiment conditions: [catalyst] = 0.5 mg mL-1, T = 20 °C, p = 1 bar, volume = 1630 mL.

Fig. 3. In-situ XPS spectra of Ag-TiO2 (a), Pt-TiO2 (b), and Pd-TiO2 (c). In-situ DRIFTS spectra of Ag-TiO2 in H2O (d) and D2O (e) under light irradiation. (f) Time-resolved intensity maps of D-O vibrations in the in-situ DRIFTS Ag-TiO2, Pt-TiO2, and Au-TiO2. Time-dependent evolution of C=C bands (1540 cm-1) (g) and C-H(sp3) bands (2958 cm-1) (h) of Ag-TiO2 and Pt-TiO2 in D2O and C3H6 under light irradiation.

References

[1]	Q. Dan, Y. Chiu, N. Lee, J. Pereira, B. Rad, X. Zhao, K. Deng, Y. Rong, C. Zhan, Y. Chen, S. Cheong, C. Li, J. W. Gin, A. Rodrigues, T. R. Northen, T. W. H. Backman, E. E. K. Baidoo, C. J. Petzold, P. D. Adams, J. D. Keasling, Nat. Catal., 2025, 8, 147-161.
[2]	A. S. K. Lahdenperä, J. Dhankhar, D. J. Davies, N. Y. S. Lam, P. D. Bacoş, K. de la Vega-Hernández, R. J. Phipps, Science, 2024, 386, 42-49.
[3]	M.-H. Jo, J.-H. Ju, S.-Y. Heo, J. Cho, K. J. Jeong, M.-S. Kim, C.-H. Kim, B.-R. Oh, Biotechnol. Biofuels Bioprod., 2023, 16, 18.
[4]	T. Marshall-Roth, N. J. Libretto, A. T. Wrobel, K. J. Anderton, M. L. Pegis, N. D. Ricke, T. Van Voorhis, J. T. Miller, Y. Surendranath, Nat. Commun., 2020, 11, 5283.
[5]	X. Wang, S.-M. Xu, A.-Z. Li, B.-J. Yuan, Q. Shi, X. Liu, M. Xu, Y. Liu, K. Kong, C. Zhang, R.-P. Li, C. Tang, Z. Chen, B.-J. Li, H. Duan, J. Am. Chem. Soc., 2025, 147, 23090-23102.
[6]	M. Ko, Y. Kim, J. Woo, B. Lee, R. Mehrotra, P. Sharma, J. Kim, S. W. Hwang, H. Y. Jeong, H. Lim, S. H. Joo, J.-W. Jang, J. H. Kwak, Nat. Catal., 2022, 5, 37-44.
[7]	J. Dong, J. Xu, Z.-D. Meng, Z.-A. Nan, W. Li, R. N. Zare, Z.-Q. Tian, F.-R. Fan, J. Am. Chem. Soc., 2025, 147, 16060-16069.
[8]	C. Dong, Y. Wang, Z. Deng, W. Wang, M. Marinova, K. Ben Tayeb, J.-C. Morin, M. Dubois, M. Trentesaux, Y. G. Kolyagin, M. N. Tran, V. Martin-Diaconescu, O. Safonova, J. Zaffran, A. Y. Khodakov, V. V. Ordomsky, Nat. Commun., 2024, 15, 8210.
[9]	S. Zhang, B. Xia, Y. Qu, L. Jing, M. Jaroniec, J. Ran, S.-Z. Qiao, Sci. Adv., 2023, 9, eadk2407.
[10]	F. Xu, W. Mei, P. Hu, L. Zheng, J. Zhang, H. Cao, H. García, J. Yu, Angew. Chem. Int. Ed., 2025, 64, e202513364.
[11]	M. Cabrero-Antonino, A. Uscategui-Linares, R. Ramírez-Grau, P. García-Aznar, G. Sastre, J. Zhang, S. Goberna-Ferrón, J. Albero, J. Yu, H. García, F. Xu, A. Primo, Angew. Chem. Int. Ed., 2025, 64, e202503860.
[12]	X. Sun, J. Liu, Q. Li, C. Wang, B. Jiang, Chin. J. Catal., 2025, 73, 358-367.
[13]	Q. Pang, Y. Wu, Y. Yang, J. Wu, J. Lu, Y. Xie, Chem. Eng. J., 2025, 525, 170098.
[14]	C. D. Zeinalipour-Yazdi, J. Mol. Model., 2024, 30, 58.
[15]	S. Jiang, Y. Liu, R. Yang, K. Deng, Z. Wang, Y. Xu, L. Wang, H. Yu, H. Wang, Appl. Catal. B, 2026, 381, 125896.
[16]	F. Benaliouche, Y. Boucheffa, F. Thibault-Starzyk, Microporous Mesoporous Mater., 2012, 147, 10-16.