ENERGY & FUELS
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2022
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IF 4.654
Wei Zhang,Jie Zhao,Ahmed A. Allam,Yue Xin,Jingqi Lin,Ting Gao,Jamaan S. Ajarem,Ximing Li,Chuanyi Wang,Detlef W. Bahnemann
Bi2WO6 is a promising photocatalyst for NOx removal, owing to its wide solar light absorption and specific photoelectric properties. Nevertheless, enhancing its efficiency remains a major concern. Palladium proves to be a good co-catalyst for semiconductor materials, but how the combination of Pd and bismuth tungstate affects the efficiency of NO removal and relevant process is still vague. In this work, nutshell-like bismuth tungstate was synthesized using a hydrothermal method, followed by photo-depositing Pd nanoparticles with different contents. The obtained photocatalysts were characterized by X-ray diffraction, specific surface area analyzer (BET), X-ray photoelectron spectroscopy, and scanning electron microscopy. Among the prepared photocatalysts, Bi2WO6 deposited with 1 wt % Pd shows the best photocatalytic activity with a NO removal efficiency of 58%, which is 2.9 times that of the Bi2WO6 under the same conditions. The enhanced photocatalytic activities were attributed to the comprehensive effects of the high efficiency in separating electrons and holes, improvement in invisible light utilization and BET specific surface areas of Pd–Bi2WO6 nanocomposites. More importantly, it was found that NO2 is the main product over Bi2WO6, whereas the conversion of NO to NO3– (an environmentally friendly product) is dominant over Pd-modified Bi2WO6 due to the enhanced separation of electrons and holes. Active species capture experiments show that photo-generated holes (h+) and •O2– play an important role in NO removal. The present work provides new insights into the role of Pd cocatalysts in NO removal.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
MOLECULES
·
2023
·Vol. 28
·期 14
·5296
·
IF 4.6
Zhenjiang Lu,Wenjin Qin,Juan Ma,Yali Cao,Shujuan Bao
Direct formic acid fuel cells (DFAFCs) are one of the most promising power sources due to its high conversion efficiency; relatively low carbon emissions, toxicity, and flammability; convenience; and low-cost storage and transportation. However, the key challenge to large-scale commercial applications is its poor power performance and the catalyst’s high preparation cost. In this study, a new sandwich-structured Pd/polypyrrole-graphene/Pd (Pd/PPy-Gns/Pd)-modified glassy carbon electrode (GCE) was prepared using a simple constant potential (CP) electrodeposition technique. On the basis of the unique synthetic procedure and structural advantages, the Pd/PPy-Gns/Pd shows a fast charge/mass transport rate, high electrocatalytic activity, and great stability for formic acid electro-oxidation (FAO). The mass activity of Pd/PPy-Gns/Pd electrode reaches 917 mA·mg−1Pd. The excellent catalytic activity is mainly due to the uniform embedding of Pd nanoparticles on the polypyrrole-graphene (PPy-Gns) support, which exposes more active sites, and prevents the shedding and inactivation of Pd nanoparticles. At the same time, the introduction of graphene (Gns) in the PPy further improved the conductivity of the catalyst and accelerated the transfer of electrons.Keywords:electrodeposition;polypyrrole;Pd nanoparticles;DFAFCs
研究领域:
电化学
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材料科学
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能源技术
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF CATALYSIS
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2025
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IF 6.5
Mengyu Li,Wei Zhuang,Xia Meng,Wenxia Zhang,Keke Zhang,Zhenfu Wang
Metal-enzyme integrated catalysts combine the high selectivity of enzyme catalysts with the broad substrate spectrum of metal catalysts and offer tremendous possibilities for chemoenzymatic cascade processes. However, the rational design of microenvironments in nanostructures that make metals and enzymes compatible for efficient activity still remains challenging. In this report, a nanocomposite catalyst was fabricated by integrating ultrafine Pd nanoparticles (Pd NPs) and Candida antarctica lipase B (CALB) on the hydrophobic polydopamine-coated SiO 2 (SP) to enhance the compatibility of enzyme-metal catalysts. In detail, Pd NPs were in situ reduced by PDA on the SP surface, and the obtained SP-loaded Pd (Pd/SP) was hydrophobically modified by octadecyltrimethoxysilane for the subsequent adsorption immobilization of CALB to prepare the integrated catalyst, CALB/mPd/SP. The hydrophobic PDA coating on SiO 2 not only stabilized the loaded ultrasmall Pd nanoparticles but also facilitated the activation of the immobilized lipase, which helped to improve the cascade catalytic efficiency of CALB/mPd/SP. Afterward, CALB/mPd/SP was used in a one-pot dynamic kinetic resolution (DKR) reaction of α-phenylethylamine with high conversion (>99 %), selectivity (93.9 %), and ee p (>99 %). After 25 days of storage and 5 h of sonication, CALB/mPd/SP exhibited no significant reduction in the DKR catalytic activity. This study proposed a simple and sustainable method for the preparation of enzyme-metal cascade catalysts to enhance their stability and achieve significantly increased activity through interfacial microenvironmental modulation.
研究领域:
生物化学
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催化化学
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2018
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IF 3.141
Yuangong Zhang,Xin Wen,Yongqing Shi,Ru Yue,Libin Bai,Qingtao Liu,Xinwu Ba
Sulfur-containing polymer supported palladium nanoparticles (Pd/SPMB) were prepared by using the cross-linked poly(N,N′-methylene bis(acrylamide)) (SPMB) as the platform. The SPMB was synthesized via the reversible addition–fragmentation chain transfer (RAFT) polymerization, from which the sulfur inherently exists in the RAFT polymer due to the use of thiocarbonate as the chain transfer agent, and could be further utilized as a modifier of Pd nanoparticles. The Pd/SPMB showed size-dependent activity and selectivity in the semihydrogenation of alkynes to alkenes. The catalyst with an average Pd size of 5.3 nm was active in the semihydrogenation of both internal and terminal alkynes. Most of the surface of Pd NPs was covered (or poisoned) by sulfide and thiolate due to the moderate complexation strength between Pd NPs and SPMB, thus leading to the selectivity enhancement toward alkene. Furthermore, the catalyst was highly stable and can be reused 10 times without an appreciable loss in either activity or selectivity.
研究领域:
化学工程
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材料科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2021
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IF 13.273
Ming Lei,Yao Tang,Huimin Wang,Lihua Zhu,Guihua Zhang,Yu Zhou,Heqing Tang
It is still very difficult to achieve rapid cleavage of C-Cl bond of highly-chlorinated benzenes by catalytic reduction process under mild conditions. By using pentachlorobenzene (PentaCB) as a representative of highly-chlorinated benzenes, we proposed a strategy to achieve rapid and complete dechlorination of highly-chlorinated benzenes by exploiting palladium with low content deposited g-C 3 N 4 (Pd/g-C 3 N 4 ) as a catalyst with NaBH 4 as a reductant. Under favorable conditions, this strategy yielded a dechlorination efficiency of 100% for PentaCB (0.4 mmol L −1 ) in methanol solution at 30 °C within 20 min, and especially the consumption of NaBH 4 is as low as 10 mmol L −1 with a molar ratio of Cl atoms to NaBH 4 of only 1:5. A hydro-dechlorination pathway was confirmed to dominate the dechlorination of PentaCB, which involves active hydrogen species (H*) as being identified by electron spin resonance (ESR) monitoring and isotope labelling experiments. The dechlorination rate constant value of chlorobenzenes (CBs) was only a little dependent on the number of chlorine atoms and the chlorine atom with smaller steric hindrance was prior to be substituted by H*. A catalytic mechanism that Pd nanoparticles played an important role on both the weakening/breaking of C-Cl bond and the formation of active hydrogen species was further clarified: Pd exerts affinity interaction on chlorine atoms at ortho -position of CBs molecules to form adsorbed state [CBs] ads ; H* was formed on the Pd surface due to its strong ability in H* retainment; subsequently the generated H* attacks the C-Cl bond in [CBs] ads to achieve hydrodechlorination. The new method provides a highly efficient method to remove halogenated pollutants.
研究领域:
环境科学
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催化化学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2025
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IF 13.2
Tangxin Zhang,Hao Zhang,Tiantian Zhu,Yuhua Mao,Jiayuan Wang,Lingyu Zhu,Jianli Wang
In de-oxygen water preparation, it is still a challenge to develop a highly efficient catalyst with less pollution on produced water. Herein, we invented a novel catalytic membrane, in which palladium nanoparticles were well dispersed and exposed sufficiently to the fluid with the help of hydrophilic polymer networks. These catalytic membranes created by dynamic filtration and reversible fixation offer exceptional flexibility in preparation and application. An apparatus for flexible and continuous chemical removal of dissolved oxygen from water was built up and applied to determine the performance of catalytic membranes. When the residence time was 32.3 s, the concentration of DO could be reduced to 10 ppb by a tri-layer catalytic membrane at ambient temperature. This uniquely configured catalytic membrane could be applied in portable and flexible DO requirements, such as experimental setups and pretreatment of instruments.
研究领域:
材料科学
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环境工程
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2015
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IF 4.097
Jing-He Yang,Haitang Yang,Shanhu Liu,Liqun Mao
The graphite-supported palladium (Pd/Grp) nanocomposite modified glassy carbon (GC) electrode was fabricated and their catalytic properties towards nitrite were studied. Pd/Grp was synthesized by microwave-assisted hydrogen reduction of palladium (II) acetate with graphite power. TEM displayed a high density of slightly aggregated Pd nanoparticles loading on the surface of graphite power with a diameter of 5–15 nm. The electrode exhibits enhanced electro-catalytic behavior to the oxidation of nitrite compared to the activated carbon-supported palladium and SiO 2 -supported palladium modified GC electrode. Under the optimal conditions, the Pd/Grp modified GC electrode can be used to determine nitrite concentration in a wide linear range and a limit of detection of 0.071 μM at a signal-to-noise ratio = 3 (S/N = 3). The sensitivity of the electrode was 0.29 μA μM −1 cm −2 .
研究领域:
材料科学
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分析化学
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
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2023
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IF 3.8
Muhammad Sohail Bashir,Aqsa Safdar,Adnan Ibrahim,Inas A. Ahmed,Syed Shoaib Ahmad Shah,Ahsanullah Unar,Hanadi A. Almukhlifi,Ahmad M. Saeedi,Wang Fuzhou
Developing facile approaches for fabrication of supported metallic nanoparticle (NPs) catalysts, and nascent technologies for their efficient application are highly desired. Herein, one-pot approach is developed for anchoring of palladium (Pd) nanoparticles on porous polyurea (PPU). In this process, tolylene-2,4-diisocyanate was poured to a mixture of water, acetone and palladium acetate at a fixed rate. After that, NaBH 4 was added to the reaction mixture to obtain Pd/PPU with highly porous morphology. The obtained hybrid composite Pd/PPU was characterized by NMR, BET, SEM, XRD, TEM, ICP-OES, and XPS techniques. The outcomes revealed the efficacious anchoring and uniform dispersion of Pd with average size of 7.81 nm onto PPU containing highly porous structure with surface area of 115.51 m 2 /g. A packed-bed reactor was designed by using Pd/PPU for flow-through catalytic reduction of harmful hexavalent chromium (Cr(VI)) to benign trivalent (Cr(III)) with formic acid as reducer from water. A good permeation flux of 20,000 L/m 2 /h with > 99% of Cr(VI) reduction efficiency were obtained. Moreover, it was observed that Pd/PPU was a highly stable (>96% efficiency for 15 h used) catalyst for flow-through transformation of Cr(VI) to Cr(III). This report therefore proposes a facile approach for synthesis of PPU-based Pd, for continuous flow catalytic remediation of wastewaters, an emerging technology.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
ENVIRONMENTAL RESEARCH
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2020
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IF 5.715
Zhen-Ni Yang,Ya-Nan Hou,Bo Zhang,Hao-Yi Cheng,Yang-Chun Yong,Wen-Zong Liu,Jing-Long Han,Shuang-Jiang Liu,Ai-Jie Wang
Biologically synthesized palladium nanoparticles (bio-Pd) have attracted considerable interest as promising green catalysts for environmental remediation. However, the mechanisms by which microorganisms produce bio-Pd remain unclear. In the present study, we investigated the roles of Shewanella oneidensis MR-1 and its NADH dehydrogenases and hydrogenases (HydA and HyaB) in bio-Pd production using formate as the electron donor. The roles of NADH dehydrogenases and hydrogenases were studied by inhibiting NADH dehydrogenases and using hydrogenase mutants (Δ hydA , Δ hyaB , and Δ hydA Δ hyaB ), respectively. The results showed ~97% reduction of palladium by S. oneidensis MR-1 after 24 h using 250 μM palladium and 500 μM formate. Electron microscopy images showed the presence of bio-Pd on both the outer and cytoplasmic membranes of S. oneidensis MR-1. However, the inhibition of NADH dehydrogenases in S. oneidensis MR-1 resulted in only ~61% reduction of palladium after 24 h, and bio-Pd were not found on the outer membrane. The mutants lacking one or two hydrogenases removed 91–96% of palladium ions after 24 h and showed more cytoplasmic bio-Pd but less periplasmic bio-Pd. To the best of our knowledge, this is the first study to demonstrate the role of NADH dehydrogenases of S. oneidensis MR-1 in the formation of bio-Pd on the outer membrane. It also demonstrates that the hydrogenases (especially HyaB) of S. oneidensis MR-1 contribute to the formation of bio-Pd in the periplasmic space. This study provides mechanistic insights into the production of biogenic metal nanoparticles towards their possible use in industrial and environmental applications.
研究领域:
微生物学
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环境科学
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纳米生物学
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产品关联
DOI
PubMed
高影响因子
Nanomaterials
·
2020
·Vol. 10
·期 8
·1612
·
IF 4.324
Zhaoyu Wen,Qiong Fu,Jie Wu,Guangyin Fan
Simple and efficient synthesis of a nano-catalyst with an excellent catalytic property for hydrogen generation from hydrolysis of dimethyl amine-borane (DMAB) is a missing piece. Herein, effective and recycled palladium (Pd) nanoparticles (NPs) supported on soft nitriding porous carbon (NPC) are fabricated and applied for DMAB hydrolysis. It is discovered that the soft nitriding via a low-temperature urea-pretreatment induces abundant nitrogen-containing species on the NPC support, thus promoting the affinity of the Pd precursor and hindering the agglomeration of formed Pd NPs onto the NPC surface during the preparation process. Surface-clean Pd NPs with a diameter of sub-2.0 nm deposited on the NPC support (Pd/NPC) exhibit an outstanding catalytic performance with a turnover frequency (TOF) of 2758 h−1toward DMAB hydrolysis, better than many previous reported Pd-based catalysts. It should be emphasized that the Pd/NPC also possesses a good stability without an obvious decrease in catalytic activity for DMAB hydrolysis in five successive recycling runs. This study provides a facile but efficient way for preparing high-performance Pd catalysts for catalytic hydrogen productions.Keywords:nano-catalyst;dimethyl amine-borane;palladium nanoparticles;hydrolysis;soft nitriding
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Reaction Kinetics Mechanisms and Catalysis
·
2024
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IF 1.7
Sun Min,Chu Siyu,Lv Denghong,Li Bin,Kang Liping
In order to promote the application of carbon dots as carriers in oxygen reduction reaction, CD with uniform size distribution was prepared by microwave heating using citric acid and urea as raw materials through a bottom-up synthesis method. Due to the presence of a large number of hydroxyl groups on the surface of CD. We found that the prepared CD can be used as a reducing agent and stabilizer to directly reduce PdCl 2 to obtain Pd nanoparticles under oil bath conditions. The obtained Pd/CD system has excellent catalytic effect on the electrocatalytic oxygen reduction. The results show that the half-wave potential of Pd/CD-0.1 catalyst reaches 0.83 V, which is comparable to that of commercial Pd/C, and the corresponding limiting diffusion current density is even larger than that of commercial Pd/C catalyst. After a 5000 cycles stability test, the LSV exhibits a left shift of only 19 mV.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
Journal of Energy Chemistry
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2020
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IF 7.216
Tao Jiang,Peng Lu,Meng-Jiao Xu,Jian-Dong Lin,Yong-Mei Liu,Yong Cao,He-Yong He
We describe herein that the quasi-one-dimensional confinement effect of functionalized nanoporous supports is particularly advantageous for boosting formic acid (FA) dehydrogenation efficiency over palladium nanoparticles (NPs). Benefiting from their unique structural merits that lead to significant lowering of the entropic barrier for FA activation, the Pd NPs interiorly located on the amino-modified MCM-41 offer the promise of more than an order of magnitude speedup of the initial activity in H 2 production from FA over their exterior analogs. Under mild and additive-free conditions, ultrafine Pd NPs confined in amino-modified MCM-41 channels exhibit an initial turnover frequency as high as 46,677 h −1 and a turnover number up to 1,060,000 at 60°C. In conjunction with the enhancement and robust performance for efficient regeneration of FA via CO 2 hydrogenation, the presented approach greatly contributes to the development of FA-based hydrogen storage and related technologies as viable means of enabling sustainable future energy prospects.
研究领域:
化学
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能源材料科学
✓ 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）