ACS Sustainable Chemistry & Engineering
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2024
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IF 7.1
Xiaoyu Shi,Yang Yang,Xin Ye,Heng Zhong,Chunling Wang,Fangming Jin
Catalytic conversion of cellulosic biomass into polyols is an effective approach for biomass upgrading. However, the conversion involves cascade reactions which require various catalytic sites cooperation for activating specific steps, resulting in low efficiency. Here, we propose a bifunctional catalyst containing acid sites and hydrogenation capacity for polyol production with cellobiose as the model compound of cellulose. Phosphonic acids (PAs) containing either methyl (MPA) or aminomethyl (NH2MPA) tails were used to tune the Pd/Al2O3 catalyst to form monolayers, thereby modulating the surface physiochemical properties and introducing multiple catalytic sites. An increasing ratio of PdO/Pd and a strong metal–support interaction were observed after PA modification, which could boost the hydrogenation activity for cellobiose. Furthermore, Pd/Al2O3-MPA exhibited excellent hydrolytic hydrogenation activity due to the increase of Lewis acid sites with good durability under hydrothermal conditions by MPA modification, achieving a 78.5% yield of sorbitol at 180 °C for 5 h. A plausible mechanism for enhancing the synergistic effect of Pd and support over Pd/Al2O3-MPA was also proposed. This investigation provides a novel strategy for rationally designing hydrothermally stable bifunctional catalysts to utilize biomass in a more effective way.
研究领域:
催化化学
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生物质能
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产品关联
DOI
高影响因子
ACS Catalysis
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2024
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IF 11.3
Minghua Dong,Sen Luan,Yuxuan Wu,Bin Zhang,Ye Liu,Huizhen Liu,Buxing Han
Unveiling the mechanism behind catalyst-dependent solvent effects for hydrogenation reactions is critically important yet presents significant challenges. In this work, focusing on furfural hydrogenation over Pd-based catalysts, we observe that distinct active hydrogen species present on Pd/MgO and Pd/TiO2 exhibit different responses to solvation environments, consequently influencing the selectivity in diverse solvents. Product distribution over Pd/MgO remains unaffected by the solvents used that tetrahydrofurfural (THFAL) emerged as the primary product in both organic solvents and water. Conversely, product distribution over Pd/TiO2 highly depends on the solvents; THFAL dominates in organic solvents, whereas furfural alcohol (FOL) becomes the primary product in water. The disparate selectivity upon alteration of supports and solvents is demonstrated by neural network-enhanced molecular dynamics simulations and microkinetic modeling. The active hydrogen species on the support are stabilized in water by water-mediated charge reconstructions, facilitating the hydrogenation of C═O to produce FOL. A spillover pathway where hydrogen species transfer to supports directly without involving hydrogen bond networks is dynamically preferred in both water and organic solvents.
研究领域:
催化化学
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理论计算化学
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DOI
高影响因子
APL Materials
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2023
·Vol. 11
·期 10
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IF 6.1
Li Xia,Deng Min,Cao Tingting,Ma Jun,Geng Shuo,Ren Yuan,Yao Mengqin,Liu Fei,Dong Yonggang
Formic acid (FA, HCOOH), as a liquid chemical hydrogen storage carrier with low cost, high hydrogen content, and convenient storage and transportation, has attracted extensive attention. Pd-based catalysts for hydrogen production from FA are easy to aggregate and deactivate in the reaction process, which hinders the further development of FA as a hydrogen storage carrier. Therefore, the exploitation of carriers with simple preparation methods and excellent performance can effectively improve the catalytic activity of Pd-based catalysts. Porous carbon and SiO 2 have been widely used for their unique structural properties, and the preparation of composite carriers by combining the advantages of both is a current research hotspot. Herein, this work synthesized C–SiO 2 for the deposition of Pd nanoparticles by a one-step method, and the obtained Pd/C–SiO 2 exhibits a superior FA dehydrogenation activity with a turnover frequency value of 1278 h −1 and a favorable stability with only a slight decrease in activity after five cycles.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
Energy Technology
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2016
·Vol. 4
·期 8
·943-949
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IF 2.557
Dong Pi,Wen Zhi Li,Qi Zhao Lin,Qi Fu Huang,Hui Qing Hu,Chun Yu Shao
A series of Pd-based core–shell catalysts (Pd@SiO 2 , Pd@CeO 2 , and Pd@ZrO 2 ) supported on Si-modified Al 2 O 3 were prepared for the catalytic combustion of lean methane. Pd@SiO 2 exhibited slightly lower catalytic activity than Pd@CeO 2 and higher catalytic activity than Pd@ZrO 2 in dry conditions; however, Pd@SiO 2 had the highest catalytic activity among the three catalysts in the presence of high concentrations of water vapor. Furthermore, the Pd@SiO 2 catalyst showed good thermal stability and resistivity to water poisoning. CO chemisorption and TEM results demonstrated that the core–shell structure could help in the stabilization of the active phase compared to the uncoated Pd/Si-Al 2 O 3 catalyst. XRD and X-ray photoelectron spectroscopy results indicated that a balanced mixed phase of PdO x /Pd 0 is the main active phase of these Pd-based catalysts.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Green Energy & Environment
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2022
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IF 12.781
Daqiang Yan,Lin Zhang,Lei Shen,Runyu Hu,Weiping Xiao,Xiaofei Yang
Developing high efficient Pd-based electrocatalysts for oxygen reduction reaction (ORR) is still challenging for alkaline membrane fuel cell, since the strong oxygen adsorption energy and easy agglomerative intrinsic properties. In order to simultaneously solve these problems, Pd/Co 3 O 4 –N–C multidimensional materials with porous structures is designed as the ORR catalysts. In details, the ZIF-67 with polyhedral structure was firstly synthesized and then annealed at high-temperature to prepare the N-doped Co 3 O 4 carbon-based material, which was used to homogeneously confine Pd nanoparticles and obtained the Pd/Co 3 O 4 –N–C series catalysts. The formation of Co–N and C–N bond could provide efficient active sites for ORR. Simultaneously, the strong electronic interaction in the interface between the Pd and N-doped Co 3 O 4 could disperse and avoid the agglomeration of Pd nanoparticles and ensure the exposure of active sites, which is crucial to lower the energy barrier toward ORR and substantially enhance the ORR kinetics. Hence, the Pd/Co 3 O 4 –N–C nanocompounds exhibited excellent ORR catalytic performance, ideal Pd mass activity, and durability in 0.1 mol L −1 KOH solution compared with Co 3 O 4 –N–C and Pd/C. The scalable synthesis method, relatively low cost, and excellent electrochemical ORR performance indicated that the obtained Pd/Co 3 O 4 –N–C electrocatalyst had the potential for application on fuel cells.
研究领域:
材料科学
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能源科学
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产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2024
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IF 7.4
Yanling Hu,Jianding Li,Qianqian Wang,Xueqing Yu,Yao Kang,Tengfei Cheng,Liqing He,Linfeng Zhang
In order to further boost the electrocatalytic performances of small organic molecule oxidation and maintain the structure stability of Pd-based catalyst during long cycle, a new ligand compound ( i.e . propanethiol) was introduced into the Pd/C anode catalyst to prepared Pd/C-SH catalyst by two main steps of propanethiol adsorbed on Vulcan XC-72 carbon (C-SH) by water bath impregnation method and Pd nanoparticles anchored on the functionalized C-SH support by improved liquid reduction method. Results showed that the Pd nanoparticles with high dispersion in Pd/C-SH catalyst were obtained and their particle size distribution was in the range of 1.6–4.8 nm. Moreover, Pd particle size became smaller with the modification of propanethiol, indicating that propanethiol could facilitate the formation of smaller Pd. Electrochemical measurements showed that the mass activity of Pd/C-SH (1229 mA mg −1 ) was 4.6 times that of Pd/C (267 mA mg −1 ) towards formic acid oxidation. Higher stability (30 times higher than Pd/C) and more faster charge transfer kinetics of oxidation reaction were also recorded for Pd/C-SH catalyst. The enhancement of electrochemical performances of Pd/C-SH catalyst might be related to highly dispersed Pd with reduced particle size, adjusted electronic structure of Pd as well as maintained stable Pd structure and particle size.
研究领域:
催化化学
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电化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2025
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IF 2.5
Fangxu Lu,Song Wen,Jie Jiang,Jinchong Zhao,Changsheng Zhang,Junjie Feng,Jing Zhang,Bing Sun,Wei Xu
It is generally acknowledged that the crystal structure of the support plays a crucial role in the catalytic performance, however, the exact role of crystal structure in the catalytic system remains controversial. The Pd/TiO2 catalysts designed in this study with different crystals (rutile (r) and anatase (a)) were employed to study the effects of the crystal structure via a probe reaction for oxygen removal under a hydrogen atmosphere. Under the same reaction conditions, the temperature to achieve 90% O2 conversion on Pd/a-TiO2 could reach up to 150 °C, which is ∼1.4 times (107 °C) that of the Pd/r-TiO2 catalyst. Based on the various characterization results, it is found that strong metal support interactions (SMSIs) are dominant on the Pd/r-TiO2 catalyst, which could facilitate the formation of oxygen vacancies and Pd2+ species in the active sites, resulting in excellent catalytic performance. This study not only improves the understanding of the distinctive structural properties of TiO2 crystal support but also offers an effective strategy to design efficient heterogeneous catalysts via tuning SMSIs.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
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2024
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IF 5.8
Kuan Ding,Junheng Zhang,Zhihan Wu,Wangliang Li,Yuming Zhang,Shu Zhang
Catalytic ketonization of biomass is an effective approach for the deoxygenation of bio-oil and the enrichment of high-purity ketone products. However, the bio-oil contains a large amount of furanic components with oxygenated side groups (e.g., furfural, furfuralcohol, etc.), which severely hinders the efficiency of the ketonization reaction. In response to this challenge, this study employed Pd-based catalysts for selective conversion of furfural into "keto-friendly" components, thereby mitigating their inhibitory effects. Initially, three morphologies of CeO 2 (the main catalyst for ketonization) were selected to investigate their influence on furfural conversion. It was found that the products were mainly furfural (exceeding 86 %), with only up to approximately 13 % of "keto-friendly" products (mainly furans) detected, indicating that pure CeO 2 exhibits a weak catalytic effect on the effective conversion of furfural. Compared with pure CeO 2 , the yield of "keto-friendly" products increased significantly when 1 wt% Pd was loaded, demonstrating the excellent catalytic performance of Pd in the effective conversion of furfural. Co-doping of Pd and Zr (5 wt%) on CeO 2 further increased the "keto-friendly" products to 66 %, suggesting a synergistic effect of Pd and Zr. Mechanism analysis revealed that Pd promotes the formation of furans and benzenes by enhancing the decarbonylation of furfural and subsequent furan ring opening reactions, while the competing carbonyl hydrogenation pathway is weakened. The findings of this study will be beneficial for enhancing the biomass ketonization conversion, thereby providing valuable references for the high-value utilization of biomass.
研究领域:
能源化学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
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IF 13.3
Siqi Wu,Jianshan Chen,Rong Guo,Haoyi Tong,Shanshan Zong,Zhifang Diao,Yeyan Qin,Yuangen Yao
Efficient production of dimethyl carbonate (DMC) from methyl nitrite (MN) carbonylation based on PdCu/NaY zeolite catalysts is highly desired for industrial applications. The introduction of boron species into the initial gels of NaY synthesis is a cost-effective modification strategy for boosting the catalytic performance. It not only introduces trace amounts of framework boron but also regulates the distribution of framework aluminum (Al F ) species. Most importantly, the synergistic effect of framework boron and Al-rich region significantly enhanced the metal − support interaction, thus promoting more electrons to be transferred from metal to support. This strategy allows the palladium active species to remain in an electron-deficient state more easily. The carbon monoxide (CO) adsorption and the critical intermediate species *CH 3 COO are more easily formatted on PdCu/NaBY catalyst, which leads to superior weight-time yields (WTY DMC up to 1507·g·kg cat − 1 ·h − 1 ), and CO conversion to DMC (C CO up to 83 %). Our design is of great importance for developing metal-zeolites catalysts, which motivates the industrial application of Pd-based catalysts in the MN carbonation of DMC field.
研究领域:
催化化学
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材料科学
✓ 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）