AgPd-Co3O4级联活性位点调节•OH生成促进光催化甲烷制甲醇

doi:10.1016/S1872-2067(25)64854-6

摘要/Abstract

摘要：

甲烷(CH₄)在地球上的储量丰富, 在温和条件下将其直接转化为甲醇(CH₃OH)是一种极具吸引力的高值转化路线. TiO₂基催化剂以其优秀的C−H活化性能而被广泛用于甲烷光催化选择性转化. 然而, 在TiO₂表面容易产生的羟基自由基(•OH)会引起持续的氧化过程, 导致CH₄转化为HCHO和CO₂等产物. 此外, TiO₂晶格氧对反应中间体的强吸附能力, 也会诱导过氧化产物的形成. 因此, 要实现CH₃OH的高选择性生成, 需要同时抑制过量•OH的释放并缓解晶格氧的强吸附效应. 构建级联活性位点是调控自由基的生成和消除晶格氧不良影响的有效策略. 金属合金有助于调控O₂选择性转化为•OH, 而氧化物可以通过价态变化来改变电子结构, 从而调控载体表面•OH的释放速率和•CH₃与晶格氧的强相互作用. 因此, 利用这两种活性位点的协同效应可以精确调节TiO₂表面•OH生成的动力学, 进而提高CH₃OH选择性.

本文通过浸渍煅烧法与化学还原法成功制备了具有AgPd合金和Co₃O₄级联活性位点的TiO₂光催化剂. 透射电镜和X射线光电子能谱(XPS)结果证明了AgPd合金与Co₃O₄的成功修饰与电子结构的变化. 通过原位XPS表征了电子转移过程, 证明了AgPd合金为富电子位点, Co₃O₄为空穴捕获中心. 原位电子顺磁共振、气相色谱质谱联用-同位素标记实验、香豆素荧光探针实验以及自由基捕获实验证明了O₂是产生•OH和含氧液态化合物的主要氧源, 并且•OH的空间分布限制在AgPd合金活性位点处. 通过原位傅里叶变化红外光谱证明了Co₃O₄作为空穴缓冲与储存中心, 可以有效地减少HCHO和CO₂的生成. AgPd合金和Co₃O₄级联活性位点有效促进•CH₃和•OH的定向结合生成CH₃OH. 优化后的AgPd-Co/TiO₂催化剂表现出优异的CH₄光催化转化为CH₃OH的性能 (4434.9 μmol·g⁻¹), CH₃OH在液态含氧化合物中的选择性高达93%, 显著优于大部分已报道的TiO₂基光催化剂.

综上, 该研究表明调控自由基生成速率的策略在提高CH₄氧化产物选择性方面展现出充分的应用潜力, 为实现温和条件下的甲烷资源升级利用提供有价值的参考. 后续可以借助多维原位表征和理论预测等方式深入研究CH₄光催化转化机制, 并进一步将策略拓展至导向生成HCHO甚至多碳产物等高值化学品.

关键词: 甲烷转化, AgPd合金, Co₃O₄, TiO₂, 光催化

Abstract:

The direct conversion of methane into methanol under mild conditions represents a highly appealing pathway. Regulating the generation of hydroxyl radicals (•OH) is a representative method, but excessive release of •OH will inevitably lead to the over-oxidation of CH₃OH. Here, we design AgPd alloy and Co₃O₄ cascade active sites on the TiO₂ surface (AgPd-Co/TiO₂) to control the release rate of •OH to improve the selectivity of CH₃OH. By incorporating Co₃O₄ as a hole buffer and storage center, the kinetics of •OH generation at the TiO₂ interface can be effectively modulated. This confines the spatial distribution of •OH to the active sites of the AgPd alloy, thus facilitating the directional combination of •CH₃ and •OH. The optimal AgPd-Co/TiO₂ photocatalyst demonstrates outstanding catalytic performance with the selectivity of CH₃OH reaching up to 93% in the liquid phase. AgPd-Co/TiO₂ exhibited significantly enhanced selectivity relative to reported TiO₂-based photocatalytic systems, while simultaneously achieving comparable methanol yields. This research offers valuable insights for the precise design of composite photocatalysts to achieve highly selective methane oxidation.

Key words: Methane conversion, AgPd alloy, Co₃O₄, TiO₂, Photocatalysis

梁舒淇, 肖针, 沈锦妮, 戴文新, 张子重. AgPd-Co₃O₄级联活性位点调节•OH生成促进光催化甲烷制甲醇[J]. 催化学报, 2026, 80: 189-199.

Shuqi Liang, Zhen Xiao, Jinni Shen, Wenxin Dai, Zizhong Zhang. Tuning radical generation rate for efficient CH₄ photooxidation to CH₃OH over AgPd alloy and Co₃O₄ cascade active sites[J]. Chinese Journal of Catalysis, 2026, 80: 189-199.

×
扫码分享

导出引用管理器 EndNote|Ris|BibTeX

链接本文: https://www.cjcatal.com/CN/10.1016/S1872-2067(25)64854-6

https://www.cjcatal.com/CN/Y2026/V80/I1/189

图/表 6

Fig. 1. (a,b) XRD patterns of different photocatalysts. (c,d) TEM images of Ag1Pd0.5-1Co/TiO2. (e) High-resolution TEM of Ag1Pd0.5-1Co/TiO2. (f) Element mapping of Ag (pink), Pd (cyan), Co (yellow) of Ag1Pd0.5-1Co/TiO2. XPS spectra for Ag 3d (g), Pd 3d (h), and Co 2p (i) of different photocatalysts.

Fig. 2. (a) Performance test of samples featuring different Ag loading ratios. (b) Photocatalytic CH4 oxidation performance over TiO2, Ag1Pd0.5/TiO2, 1 wt% Co3O4/TiO2, Ag1Pd0.5-1Co/TiO2. (c) Comparisons with the representative photocatalysts on the yield and selectivity of CH3OH in liquid phase. Effect of CH4 pressure (d) and O2 pressure (e) on photocatalytic CH4 oxidation into CH3OH over Ag1Pd0.5-1Co/TiO2. (f) Effect of H2O volume on photocatalytic CH4 oxidation into CH3OH over Ag1Pd0.5-1Co/TiO2.

Fig. 3. In situ XPS spectra of Ti 2p (a), O 1s (b), Co 2p (c), Ag 3d (d), and Pd 3d (e) in dark and under light irradiation for 10 min. (f) Time-resolved PL spectra of TiO2, 1 wt% Co3O4/TiO2, and Ag1Pd0.5-1Co/TiO2.

Fig. 4. (a) In-situ EPR spectra of DMPO-·OH over different photocatalysts. (b) Radical trapping agent experiment over Ag1Pd0.5-1Co/TiO2. (c). GC-MS spectra of CH3OH produced in the presence of 18O2 and H216O or 16O2 and H218O over Ag1Pd0.5-1Co/TiO2. (d) PL spectra of 7-hydroxycoumarin by ?OH radicals generated over Ag1Pd0.5-1Co/TiO2 with or without O2 incorporation. (e) DMPO-·OH over Ag1Pd0.5-1Co/TiO2 with the addition of scavengers at different concentrations. (f) The relationship between the relative intensity of ?OH in metal-loaded catalysts and the selectivity of CH?OH in liquid products.

Fig. 5. (a) Gibbs free energy profiles for O2 hydrogenation on AgPd/TiO2 and AgPd-Co/TiO2. The numbers in parentheses denote the electron transfer to oxygen. Color code: light blue (Ti), red (lattice O), cyan (Pd), gray (Ag), blue (Co), orange (oxygen), and green (hydrogen) spheres. In-situ IR spectra of Ag1Pd0.5/TiO2 (b) and Ag1Pd0.5-1Co/TiO2 (c) with different light irradiation times under the atmosphere of coexistence of CH4, O2. (d) The IR absorption peaks of the relevant intermediates emerged within the range of 2250?2500 cm?1. Color code: red (Ag1Pd0.5/TiO2), blue (Ag1Pd0.5-1Co/TiO2).

Fig. 6. The reaction mechanism of CH4 photocatalytic conversion to CH3OH over Ag1Pd0.5-1Co/TiO2.

参考文献

[1]	P. Voosen, Science, 2016, 354, 1513.
[2]	A. Blankenship, M. Artsiusheuski, V. Sushkevich, J. A. van Bokhoven, Nat. Catal., 2023, 6, 748-762.
[3]	H. Song, X. Meng, Z.-J. Wang, H. Liu, J. Ye, Joule, 2019, 3, 1606-1636.
[4]	Q. Li, Y. Ouyang, H. Li, L. Wang, J. Zeng, Angew. Chem. Int. Ed., 2022, 61, e202108069.
[5]	Y. Huang, L. Zou, Y.-B. Huang, R. Cao, Chin. J. Catal., 2025, 70, 207-229.
[6]	L. Wang, S. Zhang, L. Zhang, J. Yu, Appl. Catal. B, 2024, 355, 124167.
[7]	G. Fang, J. Lin, X. Wang, Chin. J. Chem. Eng., 2021, 38, 18-29.
[8]	J. Ma, R. Long, D. Liu, J. Low, Y. Xiong, Small Struct., 2022, 3, 2100147.
[9]	J. Di, W. Jiang, Z. Liu, Trends Chem., 2022, 4, 1045-1055.
[10]	C. Zhang, J. Wang, S. Ouyang, H. Song, J. Ye, L. Shi, Sci. China Chem., 2023, 66, 2532-2557.
[11]	S. Hao, Q. Han, G. Zheng, ACS Catal., 2024, 14, 16673-16686.
[12]	Z. Xiao, J. Shen, J. Jiang, J. Zhang, S. Liang, S. Han, J. Long, W. Dai, Y. Li, X. Wang, H. Xi, X. Fu, Z. Zhang, Adv. Funct. Mater., 2025, 35, 2422726.
[13]	H. Song, X. Meng, S. Wang, W. Zhou, X. Wang, T. Kako, J. Ye, J. Am. Chem. Soc., 2019, 141, 20507-20515.
[14]	Y. Jiang, S. Li, X. Fan, Z. Tang, Nano Res., 2023, 16, 12558-12571.
[15]	Y. Nosaka, A. Y. Nosaka, Chem. Rev., 2017, 117, 11302-11336.
[16]	L. Zhang, H. Zhang, D. Zhu, Z. Fu, S. Dong, C. Lyu, Chin. J. Catal., 2024, 66, 181-194.
[17]	Y. Jiang, Y. Fan, S. Li, Z. Tang, CCS Chem., 2023, 5, 30-54.
[18]	X. Zheng, Y.-G. Fang, M. Tan, B. Chen, J. S. Francisco, C. Zhu, C. Chu, J. Am. Chem. Soc., 2025, 147, 26635-26642.
[19]	X. Li, C. Wang, J. Tang, Nat. Rev. Mater., 2022, 7, 617-632.
[20]	Y. Cao, Z. Huang, C. Han, Y. Zhou, Adv. Sci., 2024, 11, 2306891.
[21]	X. Wang, X. Xin, L. Xiong, J. Yang, T. Wang, Y. Yang, Z. Huang, N. Luo, J. Tang, F. Wang, Angew. Chem. Int. Ed., 2025, 64, e202420606.
[22]	W. H. Brune, P. J. McFarland, E. Bruning, S. Waugh, D. MacGorman, D. O. Miller, J. M. Jenkins, X. Ren, J. Mao, J. Peischl, Science, 2021, 372, 711-715.
[23]	Y. Zhou, L. Zhang, W. Wang, Nat. Commun., 2019, 10, 506.
[24]	X. Cai, S. Fang, Y.-H. Hu, J. Mater. Chem. A, 2021, 9, 10796-10802.
[25]	X. Sun, X. Chen, C. Fu, Q. Yu, X.-S. Zheng, F. Fang, Y. Liu, J. Zhu, W. Zhang, W. Huang, Nat. Commun., 2022, 13, 6677.
[26]	Z. Xiao, Z. Wan, J. Zhang, J. Jiang, D. Li, J. Shen, W. Dai, Y. Li, X. Wang, Z. Zhang, ACS Catal., 2024, 14, 9104-9114.
[27]	H. Gong, C. Deng, P. He, M. Liu, Y. Cai, Y. Yang, Q. Yang, Z. Bao, Q. Ren, S. Yao, Z. Zhang, Chin. J. Catal., 2024, 67, 61-70.
[28]	M. Huang, S. Zhang, B. Wu, Y. Wei, X. Yu, Y. Gan, T. Lin, F. Yu, F. Sun, Z. Jiang, L. Zhong, ACS Catal., 2022, 12, 9515-9525.
[29]	Y. Jiang, W. Zhao, S. Li, S. Wang, Y. Fan, F. Wang, X. Qiu, Y. Zhu, Y. Zhang, C. Long, Z. Tang, J. Am. Chem. Soc., 2022, 144, 15977-15987.
[30]	H. Tang, Y. Ma, X. Sun, M. Wang, G. Zheng, C. Zhu, M. Wang, J. Mater. Chem. A, 2023, 11, 19629-19636.
[31]	C. Xie, E. Sun, G. Wan, J. Zheng, R. Gupta, A. Majumdar, Nano Lett., 2023, 23, 2039-2045.
[32]	R. Zhang, J. Shi, L. Fu, Y.-G. Liu, Y. Jia, Z. Han, K. Yuan, H.-Y. Jiang, ACS Nano, 2024, 18, 12994-13005.
[33]	Q. Zhang, C. Yang, Y. Chen, Y. Yan, M. Kan, H. Wang, X. Lv, Q. Han, G. Zheng, Angew. Chem. Int. Ed., 2025, 64, e202419282.
[34]	M. Sun, Y. Chen, X. Fan, D. Li, J. Song, K. Yu, Z. Zhao, Nat. Commun., 2024, 15, 9900.
[35]	H. Song, X. Meng, S. Wang, W. Zhou, S. Song, T. Kako, J. Ye, ACS Catal., 2020, 10, 14318-14326.
[36]	W. Jia, Z. Cao, L. Wang, J. Fu, X. Chi, W. Gao, L.-W. Wang, Comput. Phys. Commun., 2013, 184, 9-18.
[37]	J. P. Perdew, K. Burke, M. Ernzerhof, Phys. Rev. Lett., 1996, 77, 3865-3868.
[38]	W. Jia, J. Fu, Z. Cao, L. Wang, X. Chi, W. Gao, L.-W. Wang, J. Comput. Phys., 2013, 251, 102-115.
[39]	S. Grimme, J. Comput. Chem., 2006, 27, 1787-1799.
[40]	K. Momma, F. Izumi, J. Appl. Crystallogr., 2011, 44, 1272-1276.
[41]	Q. Zhou, X. Tan, X. Wang, Q. Zhang, C. Qi, H. Yang, Z. He, T. Xing, M. Wang, M. Wu, W. Wu, ACS Catal., 2024, 14, 955-964.
[42]	P. Wu, Y. Chu, M. Wang, N. Feng, J. Xu, D. Ma, J. Ye, F. Deng, Nat. Commun., 2025, 16, 4207.
[43]	L. Luo, R. Wang, Z. Wu, Y. Xiao, J. Li, Z. Feng, F. Zhang, Angew. Chem. Int. Ed., 2025, 64, e202510032.
[44]	J. Ding, P. Du, J. Zhu, Q. Hu, D. He, Y. Wu, W. Liu, S. Zhu, W. Yan, J. Hu, J. Zhu, Q. Chen, X. Jiao, Y. Xie, Angew. Chem. Int. Ed., 2024, 63, e202400828.
[45]	Y. Nakaya, S. Furukawa, Chem. Rev., 2023, 123, 5859-5947.
[46]	W. Zhou, X. Qiu, Y. Jiang, Y. Fan, S. Wei, D. Han, L. Niu, Z. Tang, J. Mater. Chem. A, 2020, 8, 13277-13284.
[47]	L. Luo, Z. Gong, Y. Xu, J. Ma, H. Liu, J. Xing, J. Tang, J. Am. Chem. Soc., 2022, 144, 740-750.
[48]	H. Song, H. Huang, X. Meng, Q. Wang, H. Hu, S. Wang, H. Zhang, W. Jewasuwan, N. Fukata, N. Feng, J. Ye, Angew. Chem. Int. Ed., 2023, 62, e202215057.
[49]	X. Zhang, Y. Wang, K. Chang, S. Yang, H. Liu, Q. Chen, Z. Xie, Q. Kuang, Appl. Catal. B, 2023, 320, 121961.
[50]	Y. Li, K. Sun, S. Ning, P. Qiao, S. Wang, Z.-J. Wang, L. Zhu, X. Zhang, K. Peng, X.-S. Wang, D. Wang, L. Liu, H. Song, J. Ye, J. Catal., 2024, 440, 115840.
[51]	H. Zhou, F. Chen, D. Liu, X. Qin, Y. Jing, C. Zhong, R. Shi, Y. Liu, J. Zhang, Y. Zhu, J. Wang, Small, 2024, 20, 2311355.
[52]	J. Xie, X. Li, J. Guo, L. Luo, J. J. Delgado, N. Martsinovich, J. Tang, Nat. Commun., 2023, 14, 4431.
[53]	Y. Song, X. Li, H. Li, L. Wang, S. Xiao, H. Fei, G. Li, X. Song, Appl. Catal. B, 2025, 363, 124816.
[54]	Y. Yang, S. Zhao, F. Bi, J. Chen, Y. Wang, L. Cui, J. Xu, X. Zhang, Appl. Catal. B, 2022, 315, 121550.
[55]	Y. Jiang, S. Li, S. Wang, Y. Zhang, C. Long, J. Xie, X. Fan, W. Zhao, P. Xu, Y. Fan, C. Cui, Z. Tang, J. Am. Chem. Soc., 2023, 145, 2698-2707.
[56]	J. Huang, S. He, J. L. Goodsell, J. R. Mulcahy, W. Guo, A. Angerhofer, W. D. Wei, J. Am. Chem. Soc., 2020, 142, 6456-6460.
[57]	H. Yang, G. Li, G. Jiang, Z. Zhang, Z. Hao, Appl. Catal. B, 2023, 325, 122384.
[58]	W. Zhang, C. Fu, J. Low, D. Duan, J. Ma, W. Jiang, Y. Chen, H. Liu, Z. Qi, R. Long, Y. Yao, X. Li, H. Zhang, Z. Liu, J. Yang, Z. Zou, Y. Xiong, Nat. Commun., 2022, 13, 2806.
[59]	K. Zheng, Y. Wu, J. Zhu, M. Wu, X. Jiao, L. Li, S. Wang, M. Fan, J. Hu, W. Yan, J. Zhu, Y. Sun, Y. Xie, J. Am. Chem. Soc., 2022, 144, 12357-12366.
[60]	K. Zheng, Y. Wu, Z. Hu, X. Jiao, L. Li, Y. Zhao, S. Wang, S. Zhu, W. Liu, W. Yan, Y. Sun, Y. Xie, Nano Lett., 2021, 21, 10368-10376.
[61]	S. Zhu, X. Li, Z. Pan, X. Jiao, K. Zheng, L. Li, W. Shao, X. Zu, J. Hu, J. Zhu, Y. Sun, Y. Xie, Nano Lett., 2021, 21, 4122-4128.
[62]	Y. Jiang, Y. Fan, X. Liu, J. Xie, S. Li, K. Huang, X. Fan, C. Long, L. Zuo, W. Zhao, X. Zhang, J. Sun, P. Xu, J. Li, F. Dong, T. Tan, Z. Tang, J. Am. Chem. Soc., 2024, 146, 16039-16051.

AgPd-Co₃O₄级联活性位点调节•OH生成促进光催化甲烷制甲醇

Tuning radical generation rate for efficient CH₄ photooxidation to CH₃OH over AgPd alloy and Co₃O₄ cascade active sites

RichHTML

PDF

Supporting Information

可视化

摘要/Abstract

引用本文

使用本文

扫码分享

图/表 6

参考文献

相关文章 15

编辑推荐

Metrics

[1]	陈润东, 张宇航, 夏兵全, 周贤龙, 张彦昭, 刘善堂. 双功能ZnxCd_1-_xS_y/FePS₃阶梯(S)型异质结增强光催化产氢与苯甲醛性能[J]. 催化学报, 2026, 80(1): 123-134.
[2]	张璇, 周林, 闫腾, 张晓虎, 陈浩. S型共价有机框架/Ni-ZIF-8异质结的构筑及其光催化制氢性能[J]. 催化学报, 2026, 80(1): 200-212.
[3]	张琳星, 谭昌龙, 祁明雨, 唐紫蓉, 徐艺军. 小分子光催化C-N偶联反应[J]. 催化学报, 2026, 80(1): 7-19.
[4]	张金鹏, 梁腾, 陈恬, 郭美君, 余乐, 佘萍, 冉景润. 实现塑料光重整与产氢耦合实际应用的关键要素[J]. 催化学报, 2026, 80(1): 20-37.
[5]	徐燕东, 景子慧, 苏雯皓, 徐加乐, 王明亮. B-TiO₂@COF S型双功能光催化剂上过氧化氢生产与糠酸合成的协同耦合效应[J]. 催化学报, 2026, 80(1): 135-145.
[6]	王少单, 杨恒, 薛丽君, 张建军, 欧阳述昕, 温丽丽. 金属掺杂ZnIn₂S₄/TpPa-1 S型异质结: 通过调控氢吸附/脱附和内建电场促进双功能光催化[J]. 催化学报, 2026, 80(1): 159-173.
[7]	蒋浩朋, 李金河, 于晓慧, 董慧龙, 王伟康, 刘芹芹. β-酮烯胺共价键桥接的S型异质结实现同步光还原CO₂为CO以及茴香醇选择性氧化为茴香醛[J]. 催化学报, 2026, 80(1): 113-122.
[8]	季碧铖, 李希成, 高帅, 秦泽平, 汪长征, 王强, 王崇臣. 自发极化增强的空心球Bi₄Ti₃O₁₂促进高效压电光催化: 构效关系与降解机制[J]. 催化学报, 2025, 76(9): 133-145.
[9]	李世杰, 李蕊, 董珂欣, 刘艳萍, 于欣, 李文尧, 刘通, 赵再望, 张明义, 张宾, 陈晓波. 自漂浮Bi₄O₅Br₂/磷掺杂氮化碳/碳纤维布S型异质结光催化剂增强去除新兴有机污染物[J]. 催化学报, 2025, 76(9): 37-49.
[10]	封波, 冯丹宁, 裴燕, 宗保宁, 乔明华, 李伟. 缺陷氮化碳负载铜单原子用于高选择性光催化氧化甲烷制甲醇[J]. 催化学报, 2025, 76(9): 96-107.
[11]	钟威, 孟爱云, 蔡旭东, 甘义遥, 王敬涛, 苏耀荣. Co诱导不对称电荷分布弱化S-H_ad键增强NiCoS助剂的光催化制氢性能[J]. 催化学报, 2025, 76(9): 108-119.
[12]	郑相阳, 吴金往, 史海峰. 双空位诱导极化场与内建电场增强的S型异质结用于去除抗生素及六价铬[J]. 催化学报, 2025, 76(9): 50-64.
[13]	李正, 曾影, 董媛媛, 吕红金, 杨国昱. 十钨酸盐+Pd/C催化体系中金属/H⁺位点的调控用于光催化生成糠基乙醚[J]. 催化学报, 2025, 75(8): 137-146.
[14]	熊祺, 史全全, 王彬力, 李杲. 晶面诱导还原导向的AgBr/Ag⁰/TiO₂{100} Z型异质结用于四环素去除[J]. 催化学报, 2025, 75(8): 164-179.
[15]	王啟航, 孟利, 李卓, 杨卓然, 汤意南, 余浪, 李志君, 孙建辉, 井立强. 钴单原子-磷酸功能化还原氧化石墨烯/苝四羧酸纳米片异质结用于高效光催化生产过氧化氢[J]. 催化学报, 2025, 75(8): 192-203.