APPLIED CATALYSIS B-ENVIRONMENTAL
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2023
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IF 22.1
Decun Luo,Ziyu Tang,Xiyang Yu,Tao Zhang,Chun-Ran Chang,Zhun Hu
The effect of ZrO 2 crystalline phases on Pd/ZrO 2 for catalytic combustion of toluene was investigated. It was found that Pd/t-ZrO 2 showed superior activity when the toluene concentration was lower than 2000 ppm, while Pd/m-ZrO 2 performed better with toluene concentration higher than 3000 ppm. Kinetic studies showed that the reaction order of toluene on Pd/t-ZrO 2 and Pd/m-ZrO 2 is 0 and 2, respectively. The catalytic activity was controlled by combined effect of PdO activity and quantity, which was correlated with the interaction between palladium and zirconia. The t-ZrO 2 increased PdO species activity, while m-ZrO 2 could enhance the amount of PdO. DFT results showed that the p-band center of the O of PdO on t-ZrO 2 was higher, suggesting that PdO was more active. In situ -DRIFTS revealed that the reaction pathway of catalytic oxidation of toluene on Pd/ZrO 2 was as follows: toluene was oxidized stepwise to benzyl alcohol, benzaldehyde, benzoic acid , CO 2 and H 2 O.
研究领域:
催化化学
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环境科学
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材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
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2024
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IF 6.5
Yiming Chen,Chuan Wang,Yi Liu,Qianwen Zhang,Ling Zhou,Yi Zhang
The selectivity and stability of catalysts for methanol synthesis from CO 2 still remain to be enhanced. In this work, we synthesized a series of Pd/ZrO 2 catalysts inversely loaded with various metal oxide promoters (ZnO, In 2 O 3 , and CeO 2 ), those would partially cover Pd metal surface and form some new metal-promoter interface, to explore the nature in the performance of CO 2 hydrogenation to methanol. The catalyst synthesized by this approach could limit the growth of Pd particles during the reduction and form new metal–metal oxide interfaces with different functions of CO 2 hydrogenation, improving the reaction performance of Pd-ZrO 2 catalysts. As a result, the ZnO-Pd/ZrO 2 catalyst exhibited the highest CO 2 conversion (12.0 %), methanol selectivity (95.6 %), and STY of methanol (472 g MeOH kg cat -1 h −1 ), with excellent stability. The results of HRTEM, H 2 -TPR, XPS, and XAFS showed that the ZnO-Pd/ZrO 2 catalyst had the typical Pd-ZnO interface with Pd 2+ species after the H 2 reduction, which could enhance the adsorption and activation of CO 2 . In addition, the in situ DRIFTS and NAP-XPS results implied that the Pd-ZnO interface significantly improved the formation of formate (HCOO*) and methoxy (H 3 CO*) species, which were considered to be the key intermediates of methanol generation, and thus greatly enhanced the selectivity of methanol.
研究领域:
催化
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化学工程
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材料科学
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环境化学
✓ 已验证
产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
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2023
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IF 7.5
Xin Zhang,Jingyun Jiang,Hao Li
Hydrodeoxygenation (HDO) of bio-oils obtained by rapid pyrolysis of biomass into high value-added chemicals generally required harsh conditions. Herein, three kinds of mixed-phase ZrO 2 supports (denoted as ZSX, X = 2–4) with different crystal structure proportions were prepared by one-pot hydrothermal synthesis method, and their performance on the properties of Pd/ZrO 2 catalysts were investigated for vanillin HDO. Pd/ZS3 exhibited excellent efficiency in HDO of vanillin, a typical model compound of lignin, achieving approximately 100% yield of 2-methoxy-4-methylphenol (MMP) in presence of n-butanol as solvent and polymethyl hydrogen siloxane (PMHS) as hydrogen donor under mild conditions (35 °C, 1 h). It was due to catalytic synergy of exposed metal active sites, oxygen vacancies (O v ) and acid sites to occur electron transfer and enhance interaction between Pd and ZrO 2 . By tuning the crystal structure of ZrO 2 support, the influence of O v and acid sites of Pd/ZrO 2 over vanillin HDO performance was investigated, Pd/ZS2 with abundant O v and Pd/ZS4 with substantial acid sites promoted hydrogenation and hydrogenolysis , respectively, Pd/ZS3 possessed preferable conversion and selectivity as having the properties of both at once. Additionally, reaction pathway was also proposed in which vanillin was converted to MMP by combining intermediate of 4-hydroxy-methyl-2-methoxyphenol (HMP) with active hydrogen species while removing water. This developed catalysts with different crystalline highlighted an enormous promise for HDO of bio-oils into green fuel under mild conditions.
研究领域:
催化
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化学工程
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绿色化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2026
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IF 3.9
Xing Yan,Dongren Cai,Jiachang Li,Chuanlong Ran,Kok Bing Tan,Ahmad Zuhairi Abdullah,Sajid Ali,Yingfeng Chen,Guowu Zhan
Abstract Although Pd/ZrO2 represents a highly promising catalyst for CO2 hydrogenation, it still faces challenges such as low methanol selectivity and intense competing side reactions. In this study, we precisely constructed an In2O3 interfacial layer between Pd and ZrO2 by atomic layer deposition (denoted as Pd/xIn2O3/ZrO2, where x represents the number of atomic layer deposition cycles) and systematically investigated the role of this interlayer in modulating the catalyst microstructure, reaction pathways, and methanol selectivity. Catalytic performance evaluation results reveal that under reaction conditions of 320 °C and 3 MPa, the Pd/10In2O3/ZrO2 catalyst exhibits the best performance for CO2 hydrogenation to methanol, whereby the methanol selectivity was significantly enhanced from 6.6% to 76.6%, and the methanol space-time yield increased by approximately 6 times (2.40 vs. 13.37 gMeOH·gPd–1·h–1) when compared to pristine Pd/ZrO2 catalyst. Multifaceted characterization and in situ diffuse reflectance infrared Fourier transform spectroscopy demonstrate that the introduction of In2O3 substantially strengthens CO2 adsorption and activation, promotes further hydrogenation of the key CO* intermediate, and establishes a dual-path synergistic mechanism involving both formate and CO-hydrogenation routes, thereby effectively suppressing the formation of the byproduct CO. Collectively, this work demonstrates that catalyst interface engineering via atomic layer deposition provides an effective strategy for tuning the reaction network and optimizing methanol selectivity in catalytic CO2 hydrogenation systems.
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2026
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IF 12.5
Jiabao Lv,Hongman Sun,Guanying Liu,Fangzhen Wang,Xinru Qin,Shuzhuang Sun,Youhe Wang,Zifeng Yan
Mix-ZrO 2 supports have tunable monoclinic and tetragonal crystalline phases. • InPd/Mix-ZrO 2 –400 achieves 11.5% CO 2 conversion and 52% methanol selectivity. • The specific composition improves H 2 dissociation and CO 2 adsorption. • Methanol synthesis over InPd/Mix-ZrO 2 proceeds via the formate pathway. Upgrading CO 2 to methanol represents a pivotal strategy for achieving carbon neutrality, yet the development of highly efficient indium-based catalysts remains constrained by the urgent need for precise modulation of the support structure. Herein, we rationally design an In Pd catalyst supported on mixed crystal phase ZrO 2 (Mix-ZrO 2 ) with tunable monoclinic and tetragonal fractions. The optimized InPd/Mix-ZrO 2 –400 catalyst exhibits a CO 2 conversion of 11.5% and methanol selectivity of 52% at 270 °C, significantly outperforming other comparative catalysts, and retains stability over 50 h. Crucially, the enhanced performance is intrinsically attributed to the synergistic effect derived from the specific monoclinic-tetragonal phase ratio, which significantly boosts the dissociation of H 2 and CO 2 adsorption capacity. In-situ DRIFTS analysis confirms the reaction proceeds via the formate (HCOO*) pathway, where the optimized support facilitates the rapid hydrogenation of intermediates. This work elucidates the synergistic effect of crystal phase engineering in oxide supports, offering a robust pathway for designing advanced CO 2 hydrogenation catalysts.
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2023
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IF 6.7
Jinghua Li,Jia Lin,Xiaohua Chen,Meiqiu Feng,Ying Zheng
Palladium-based catalysts are relatively active for eliminating anthropogenic methane emissions through catalytic combustion, while they tend to degrade under drastic conditions. Herein, the silicon promoter was rationally introduced into Pd/ZrO 2 catalysts to tune the monoclinic ( m -) and tetragonal ( t -) phase ratio and boost the catalytic performance. The introduced Si–O–Zr structure in ZrO 2 not only reduced the grain size, but also produced oxygen vacancies due to lattice distortion, which greatly improved the stability of t -ZrO 2 in high-temperature (800 °C) calcined catalysts. However, the excessive Si-addition caused the blockage of oxygen vacancies by amorphous SiO 2 , facilitating the transformation from t -ZrO 2 to m -ZrO 2 . In the Pd/0.05Si–ZrO 2 catalyst with a relatively high t -ZrO 2 ratio, the presence of abundant oxygen vacancies stimulated the formation of surface-active oxygen and Pd 2+ species, improved the reducibility of PdO and the redox of Pd ↔ PdO, meanwhile depressed the accumulation of hydroxyls. These, coupled with the enhanced hydrophobicity by Si-modification, made Pd/0.05Si–ZrO 2 exhibit superior catalytic activity, stability and water-resistance to catalysts with low t -ZrO 2 ratio. The revealed Si-promotion effect could be generalized to design phase-regulated Pd-based catalysts with optimized surface property for catalytic oxidation reactions.
研究领域:
催化化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2025
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IF 4.3
Xing Yan,Dongren Cai,Meihong Lin,Zhijie Wu,Yegang Xia,Yanmei Cai,Sajid Ali,Kok Bing Tan,Andriambinintsoa Ranaivoson Tojonirina,Hao Sun,Guowu Zhan
The selective hydrogenation of CO 2 to methanol demands precise control of both catalyst architecture and reaction pathways. Here, we design an atomic layer deposition (ALD)-engineered Pd/ZnO/ZrO 2 ternary catalyst with atomic-scale ZnO interlayers to decouple and reconfigure active sites at dual interfaces (Pd-ZnO and ZnO-ZrO 2 ). This interfacial engineering drives a 7-fold enhancement in methanol space–time yield (0.584 vs. 0.084 g MeOH g cat −1 h −1 ) and switches the dominant reaction pathway from CO-mediated to formate-driven selectivity (methanol selectivity remarkably surges from 6 % to 64 %). Multimodal characterization and theoretical calculations reveal that ZnO interlayers orchestrate bifunctional cooperation: activating CO 2 /CO adsorption while suppressing CO/CH 4 formation through electronic effects. Long-term stability study uncovers a dynamic restructuring mechanism, where Pd-ZnO interfaces gradually evolve into PdZn β alloy phases under the reaction conditions. This work establishes ALD-mediated interface design as a generalizable strategy to manipulate reaction networks and methanol selectivity in catalytic CO 2 hydrogenation systems.
研究领域:
催化化学
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材料科学
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化学工程
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可持续能源
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表面科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）