LANGMUIR
·
2024
·
IF 3.7
Hai-Tao Ren,Chao-Chen Cai,Peng-Yue Zhu,Cong Wang,Song-Hai Wu,Yong Liu,Xu Han
Photocatalytic technology is a popular research area for converting solar energy into environmentally friendly chemicals and is considered the greenest approach for producing H2O2. However, the corresponding reactive oxygen species (ROS) and pathway involved in the photocatalytic generation of H2O2 by the Bi2.15WO6-glucose system are still not clear. Quenching experiments have established that neither •OH nor h+ contribute to the formation of H2O2, and show that the formed surface superoxo (≡Bi–OO•) and peroxo (≡Bi–OOH) species are the predominant ROS in H2O2 generation. In addition, various characterizations indicate the enhanced electron-transfer on the surface of Bi2.15WO6 with increasing contents of glucose via the ligand-to-metal charge transfer pathway, confirming H-transfer from glucose to ≡Bi–OO• or ≡Bi–OOH. The increased production of H2O2 with decreasing bond dissociation energy (BDEO–H) values of various phenolic compounds again supports the H-transfer mechanism from phenolic compounds to ≡Bi–OO• and then to ≡Bi–OOH. DFT calculations further reveal that on the Bi2.15WO6 surface, oxygen is sequentially reduced to ≡Bi–OO• and ≡Bi–OOH, while H-transfer from H2O or glucose to ≡Bi–OO• and ≡Bi–OOH, resulting in the production of H2O2. The lower energy barrier of H-transfer from adsorbed glucose (0.636 eV) than that from H2O (1.157 eV) indicates that H-transfer is more favorable from adsorbed glucose. This work gives new insight into the photocatalytic generation of H2O2 by Bi2.15WO6 in the presence of glucose/phenolic compounds via the H-abstraction pathway.
研究领域:
材料科学
·
环境科学
·
催化化学
✓ 已验证
DOI
PubMed
高影响因子
GREEN CHEMISTRY
·
2015
·Vol. 18
·期 8
·2435-2442
·
IF 8.02
Chaofeng Zhang,Jianmin Lu,Mingrun Li,Yehong Wang,Zhe Zhang,Haijun Chen,Feng Wang
We present an experimental and computational study of the elementary steps of hydrazine hydrogen transfer on crystalline MoO2, and demonstrate its unique bifunctional metallic-basic properties in a catalytic hydrogenation reaction. Density functional theory (DFT) calculations suggest that the stepwise hydrogen transfer via the prior cleavage of the N–H bond rather than the N–N bond, is the key step to create the dissociated hydride and proton species on the dual Mo and O sites, marking its difference with common oxides. Crystalline MoO2 shows exceptionally high chemoselectivity toward the nitro reduction over CC, CC, and CN groups at room temperature and lower, down to 0 °C, rendering it as a promising catalytic material for hydrogenation reactions.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
PROCEEDINGS OF THE COMBUSTION INSTITUTE
·
2024
·
IF 5.3
Wen-luan Xie,Bin Hu,Xiao Yang,Ji Liu,Zhi-mo Fang,Kai Li,Yang-wen Wu,Bing Zhang,Qiang Lu
Phosphoric acid is an effective and widely used catalyst for biomass pyrolysis, with significant catalytic impact on the pyrolytic reactions and product distribution. However, its fundamental catalytic mechanism in lignin pyrolysis remains unclear. In this work, we proposed and investigated three possible H 3 PO 4 -assisted pyrolysis mechanisms, i.e., hydrogen-bond-induced decomposition, phosphoric-acid-assisted hydrogen transfer (H 3 PO 4 -AHT), and phosphorolysis, and carefully discussed them through theoretical calculations, electronic structure analyses, catalytic pyrolysis experiments using the β -O-4 linked lignin model. The results indicated that the H 3 PO 4 -AHT mechanism played a dominant role in lignin catalytic pyrolysis, superior to the other two mechanisms. The phosphoric acid molecule could take advantage of its unsaturated P = O and saturated P −OH groups for hydrogen donation and acceptance in concerted H 3 PO 4 -AHT reactions. Alternatively, it could also participate in concerted intermolecular hydrogen transfer with the active hydroxyl group as a mediator. The C β −O bond cleavage could be significantly enhanced by effectively reducing the tension of the transition state ring, leading to the generation of more phenol and styrene in pyrolysis experiments. Due to the inhibition of hydrogen abstraction, C α −C β breakage of β -O-4 linkage, side chain removal of primary products, etc., the formation of other products in phosphoric acid catalytic pyrolysis of β -O-4 linked lignin was restrained. This H 3 PO 4 -AHT catalytic mechanism was also confirmed to be conductive to tautomerism, elimination, dehydration, α -O-4 linkage fracture, β -1 linkage fracture, and other important decomposition reactions in lignin pyrolysis. The understanding of these mechanisms provides valuable insights into the role of phosphoric acid in lignin pyrolysis and may guide the development of effective biomass catalytic conversion methods.
研究领域:
化学工程
·
生物质能
·
催化科学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2013
·
IF 3.41
Jing Chen,Shijun Huang,Jin Lin,Weiping Su
Using a supported palladium catalytic system, the reaction of nitroarenes with benzyl alcohols occurred smoothly via hydrogen transfer to produce imines in an atom-economical manner. The palladium species were dispersed well on hydrotalcite (HT) support and palladium nanoparticles with size of about 3.5 nm were formed during reaction. Both of the small size of palladium nanoparticles and the rich hydroxyl groups on HT surface enhanced the catalytic performance of Pd/HT. The catalytic system is recyclable and amenable to a variety of aromatic alcohols and nitro compounds.
研究领域:
化学
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Chemistry
·
2016
·
IF 2.322
Bingfeng Chen,Fengbo Li,Zhijun Huang,Guoqing Yuan
Furfural is directly converted to levulinate esters (isopropyl levulinate and furan-2-ylmethyl-levulinate) as potential biofuel feedstocks , through a combined catalytic strategy. Nb 2 O 5 -ZrO 2 mixed oxide microspheres are used as bifunctional catalysts for hydrogen-transfer hydrogenation and acid-catalyzed alcoholysis in isopropanol. Bifunctional catalysts improve sustainability of furfural conversion through process intensification. Hydrogen transfer hydrogenation from isopropanol avoids dangerous hydrogen gas , and abates process and environmental costs. Isopropyl levulinate and furan-2-ylmethyl-levulinate are the main products that can be applied as blending components in biodiesel or hydrocarbon fuels.
研究领域:
化学工程
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
Current Green Chemistry
·
2019
·Vol. 6
·期 2
·127-134
·
IF 0
Yu Zhaozhuo,Xu Fusheng,Li Yan,Konno Hiroyuki,Li Hu,Yang Song
Hydrogenation of furfural (FUR) to furfuryl alcohol (FFA) is a key step and one of the representative examples for comprehensive utilization of biomass, while relatively harsh conditions are typically required to achieve satisfactory results using molecular hydrogen, formic acid, or
alcohol as H-donor over expensive metal catalysts. In this work, a new and benign reaction system, composed of green and cheap tetraethylammonium fluoride and polymethylhydrosiloxane (PMHS), is developed to be efficient for transfer hydrogenation of bio-based FUR to high-value FFA under mild
conditions. After reacting at 35 132;ƒ for 0.5 h, 94.9% FUR conversion and 92.3% yield of FFA could be achieved. This protocol is also widely applicable to the selective reduction of various aromatic aldehydes, giving relevant alcohols in high yields of 81.0-99.9% at 35-60 °C within
30-120 min. Moreover, the mechanism of fluoride-activated hydrosilylation was demonstrated to be responsible for the efficient transfer hydrogenation process.
研究领域:
化学
·
能源科学
✓ 已验证
产品关联
DOI
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2023
·
IF 22.1
Baoyu Wang,Mingrui Li,Songdang Zhang,Hongguo Wu,Yuhe Liao,Hu Li
Finite size effect is closely correlated with heterogeneous catalytic activity and selectivity as reducing the metal to a few nanometers, but may suffer from deficient active sites for cascade reactions. Here, a type of dual-size heterogeneous N-doped cobalt catalysts (Co SAs-NPs /NC(n)) with the coexistence of Co single-atoms (Co-SAs) and Co nanoparticles (Co-NPs) were prepared for efficient synthesis of benzimidazoles (up to 91% yield) from 2-nitroanilines and bio-based alcohols via cascade hydrogen transfer-dehydrogenative cyclization. Experimental results and density functional theory calculations suggested that the bio-alcohol dehydrogenation mainly occurs at Co-SAs sites, while Co-NPs sites remarkably facilitate the subsequent reduction of nitro species, indicating the synergistic effect between Co-SAs and Co-NPs in the coupled hydrogen transfer process. The Co SAs-NPs /NC(0.25) catalyst can be recycled and applied to a wide range of substrates (28 examples). This catalytic approach based on the metal size effect opens a new route for the direct upgrading of biomass feedstocks involving multiple reactions.
研究领域:
催化化学
·
材料科学
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2024
·
IF 10.7
Xu Yu,Han Tian,Ziyi Yu,Fantao Kong,Chang Chen,Ziwei Chang,Jian Huang,Xiangzhi Cui,Jianlin Shi
Hydrogen spillover effect-based active catalyst design is an effective strategy to enhance the hydrogen oxidation reaction (HOR) performance, which, unfortunately, still suffers from the high hydrogen spillover energy barrier. Here, a strategy alloying Ir with Ru is proposed to modulate the electronic structure of Ir to accelerate the H* transfer by a novel Ir–Ru–WO2.72 bridge, thus significantly reducing the hydrogen spillover energy barrier from Ir to WO2.72. The IrRu nanoclusters were deposited on a three-dimensional ordered macroporous WO2.72–C framework, and thus the constructed IrRu–WO2.72–C (1.16 wt% Ir and 1.09 wt% Ru) catalyst exhibits excellent HOR and CO-tolerance performance, rather high cell power density, and especially, 4 times higher mass activity than that of Pt/C. The modulation of Ru largely decreases the work function difference between the IrRu clusters and substrate, resulting in a reduced hydrogen spillover barrier via the Ir–Ru–WO2.72 bridge, weakened CO adsorption and fast removal of the adsorbed CO.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Yue Wu,Cailing Chen,Zhuo Xiong,Meng Xu,Yue Zhao,Yihu Dai,Yu Han,Yu Zhou,Xiaoling Liu,Jun Wang
Direct hydrogen transfer amination of alcohols with amines is an environmentally friendly and atom-economical route for the synthesis of N-alkylamines. Noble metal species are highly catalytic active sites, but the exorbitant price makes the urgency to boost the atom efficiency with stable recyclability. Herein, we demonstrated that encapsulation of Ru nanoparticles (NPs) within BEA zeolite through direct hydrothermal approach greatly promoted the catalytic efficiency in the N-alkylation of aromatic alcohols and amines under additive- and solvent-free conditions, resulting in the high yield (∼93 %), maximum turnover number (TON) of 12,822 and turnover frequency (TOF) of 9012 h −1 , with stable recyclability and extendable substrate scope. The kinetic studies and in-situ characterizations revealed that the synergy of confined Ru NPs and adjacent acid sites of BEA zeolite significantly promoted the C–H bond activation in the rate-determining step of alcohol dehydrogenation into aldehydes. Besides, the acid sites also accelerated the condensation of aldehyde intermediates and anilines to promote the kinetic equilibrium, while the moderate strength of the Ru–H bond resulting from the confined Ru NPs is advantageous to balance the dehydrogenation and hydrogenation steps to reach the fascinating H-transfer process.
研究领域:
催化化学
·
材料科学
·
有机合成
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2023
·
IF 7.4
Yubo Jia,Zhuosen He,Yucui Hou,He Li,Shuhang Ren,Weize Wu
Direct coal liquefaction (DCL) is an important and effective method to convert coal into chemicals and fuel oil. Pyrite catalysts play an important role in improving the hydrogenation and liquefaction efficiency of coal. There have been many studies on its active component Fe 1-x S in promoting pyrolysis of coal and producing active hydrogen, but studies about the hydrogen migration on Fe 1-x S catalyst and the interaction between hydrogen and Fe 1-x S catalyst were rarely reported. It is significant to study the hydrogen transfer behaviors on Fe 1-x S in DCL and understand the influence of Fe 1-x S on the hydrogen migration process. In this study, the chemical adsorption and desorption of hydrogen on Fe 1-x S were firstly proved experimentally. After pre-sulfidation of Fe 1-x S, the maximum amount of H chemically adsorbed in Fe 1-x S is 8.20 mmol/g at 360 °C and 1.5 h. The dehydrogenation of Fe 1-x S in an anthracene (ANT) system and re-hydrogenation of that in the hydrogen supply systems, such as H 2 and 1,2,3,4-tetrahydronaphthalene (THN), were explored at different experiment conditions, which gave some quantitative results of hydrogen transfer. Particularly, the dehydrogenation of Fe 1-x S in the ANT system was analyzed in thermodynamics. The enthalpy of dehydrogenation of Fe 1-x S in the ANT system is 117.6 kJ mol −1 . The results break the traditional view about Fe 1-x S only as a medium for active hydrogen transfer and provides a new perspective for further understanding the hydrogen transfer process.
研究领域:
能源化学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2023
·
IF 7.5
Fa-Peng Wu,Yun-Peng Zhao,Zong-Pin Fu,Le-Le Qiu,Jian Xiao,Jian Li,Fang-Jing Liu,Jing-Pei Cao
Efficient transfer hydrogenolysis of benzyl phenyl ether (BPE) was accomplished over Ni 1.5 Cu 1.5 /Al 2 O 3 using isopropanol as hydrogen source . The characterization results demonstrated that the formation of NiCu alloy and electron transfer between Ni and Cu were responsible for the excellent catalytic performance. Isopropanol displayed better hydrogen-donating ability than other low-carbon alcohols because of its unique dehydrogenation pathway and small steric hindrance . The results of isotopic experiments elucidated that active hydrogen species for the C O bond cleavage originated from isopropanol rather than H 2 , while both isopropanol and H 2 were responsible for hydrogenation of phenol to cyclohexanol when reaction was conducted with mixed hydrogen sources. A mechanism study illustrated that transfer hydrogenolysis of BPE proceeded through direct cleavage of C O bond followed by phenol hydrogenation, in which the active hydrogen species were in the form of H + and H − .
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2025
·
IF 6.2
Liwei Ma,Jing Weng,Junjie Xue
Catalytic co-pyrolysis of biomass and hydrogen donors is one of the important ways to improve the quality of bio-oil. The hydrogen transfer pathways in co-pyrolysis are significant yet remain vague. In this study, an isotopic labeling method to label glucose (G) with deuterium (D) atoms was used to trace the hydrogen. The results show the catalysts influence the hydrogen transformation significantly and selectively. The shift of the infrared (IR) peaks proves that the hydrogen atoms in products - phenols, alcohols, carboxylic acids, aldehydes, and olefins contain both hydrogen from polypropylene (PP) and deuterium from G. While the hydrogen in aromatic rings, - CH 3 and - CH 2 all come from polypropylene. Furthermore, the deuterium atoms from G only enter the olefin products with catalyst potassium chloride (KCl) or activated carbon (AC). On the other hand, the oxygenated compound products mainly contain hydrogen atoms from polypropylene with any of the three catalysts. The potassium chloride helps the hydrogen from polypropylene transfer to the products of mainly phenols, aldehydes and alcohols. The AC transfers the hydrogen from polypropylene to the products of carboxylic acid, aldehydes, and phenols. For the ZSM-5, it helps the hydrogen from polypropylene transfer to the products of carboxylic acid and aldehydes. The results of this study are useful for improving the effective hydrogen content of the mixed pyrolysis reaction of biomass.
研究领域:
能源化学
·
催化化学
✓ 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）