ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2021
·
IF 9.028
Guangzhi He,Meng Gao,Yue Peng,Yunbo Yu,Wenpo Shan,Hong He
Mn-based oxides exhibit outstanding low-temperature activity for the selective catalytic reduction of NOx with NH3 (NH3-SCR) compared with other catalysts. However, the underlying principle responsible for the excellent low-temperature activity is not yet clear. Here, the atomic-level mechanism and activity-limiting factor in the NH3-SCR process over Mn-, Fe-, and Ce-based oxide catalysts are elucidated by a combination of first-principles calculations and experimental measurements. We found that the superior oxidative dehydrogenation performance toward NH3 of Mn-based catalysts reduces the energy barriers for the activation of NH3 and the formation of the key intermediate NH2NO, which is the rate-determining step in NH3-SCR over these oxide catalysts. The findings of this study advance the understanding of the working principle of Mn-based SCR catalysts and provide a fundamental basis for the development of future generation SCR catalysts with excellent low-temperature activity.
研究领域:
催化化学
·
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
iScience
·
2023
·
IF 5.8
Zhixin Li,Yan Zhang,Qianqian Yang,Jindong Wu,Zhi Ren,Fengzhan Si,Jing Zhao,Jiean Chen
Hydrogen is one of the most promising future energy sources due to its highly efficient energy storage and carbon-free features. However, the energy input required for a hydrogen production protocol is an essential factor affecting its widespread adoption. Water electrolysis for hydrogen production currently serves a vital role in the industrial field, but the high overpotential of the oxygen evolution reaction (OER) dramatically impedes its practical application. The formaldehyde oxidation reaction (FOR) has emerged as a more thermodynamically favorable alternative, and the innovation of compatible electrodes may steer the direction of technological evolution. We have designed Au-Vo-NiO/CC as a catalyst that triggers the electrocatalytic oxidation of formaldehyde, efficiently producing H 2 at the ultra-low potential of 0.47 V (vs. RHE) and maintaining long-term stability. Integrated with the cathodic hydrogen evolution reaction (HER), this bipolar H 2 production protocol achieves a nearly 100% Faraday efficiency (FE).
研究领域:
能源科学
·
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
Journal of Energy Storage
·
2021
·
IF 6.583
Ying Wang,Cuili Xiang,Zuoan Xiao,Fen Xu,Lixian Sun,Jian Zhang,Yongjin Zou
Layered double hydroxides (LDHs) exhibit excellent electrochemical performance in alkali solutions. However, their low conductivity and poor cycle stability limit their application. In this work, Ni-Mn LDH was grown on activated carbon nanofibers (ACNFs) and then phosphidated to obtain an electrode material with a three-dimensional core–shell structure (ACNFs@Ni-Mn-P). This composite combines the electrochemical activity of the two-dimensional phosphidated nanosheets with the structural stability of the one-dimensional nanofibers. The resulting ACNFs@Ni-Mn-P electrode exhibits a high specific capacitance of 1077 F g −1 at 1 A g −1 , which is 4.9 times higher than that of a non-phosphidated ACNFs@Ni-Mn LDH electrode, and retains stability of 88.53% at a high current density of 10 A g −1 even after 5000 cycles. Moreover, an asymmetrical supercapacitor featuring an ACNFs@Ni-Mn-P positive electrode achieves comparatively prominent specific energy of 56.25 Wh kg −1 at 806.13 W kg −1 , respectively. Therefore, ACNFs@Ni-Mn-P as electrode material has great potential for application in supercapacitors.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Systems Microbiology and Biomanufacturing
·
2021
·Vol. 2
·期 3
·473-486
·
IF 0
Wu Aiai,Bai Yajun,Fan TaiPing,Zheng Xiaohui,Cai Yujie
l -Lactate dehydrogenases can reduce alpha-keto carboxylic acids asymmetrically and generally have a broad substrate spectrum. l -Lactate dehydrogenase gene (LF- l -LDH0845) with reducing activity towards 3,4-dihydroxyphenylpyruvate and phenylpyruvate was obtained from Lactobacillus fermentum JN248. To change the substrate specificity of LDH0845 and improve its catalytic activity towards large substrates, site-directed mutation of Tyr221 was performed by analyzing the amino acids in the active center. Kinetic parameters show that the k cat values of Y221F mutant on 3,4-dihydroxyphenylpyruvate, 4-methyl-2-oxopentanoate, and glyoxylate are 1.21 s −1 , 1.35 s −1 , and 0.72 s −1 , respectively, which are 420%, 150% and 130% of the wild-type LDH0845. This study shows that the mutations of Y221 can significantly change the substrate specificity of LDH0845, making it become a potential tool enzyme for the reduction of alpha-keto carboxylic acids with large functional groups.
研究领域:
生物化学
·
分子生物学
·
酶工程
✓ 已验证
DOI
JOURNAL OF POWER SOURCES
·
2017
·
IF 6.395
Lan Sun,Tao Wang,Long Zhang,Yunjin Sun,Kewei Xu,Zhengfei Dai,Fei Ma
The rational design and preparation of earth-abundant, stable and efficient electrocatalysts for hydrogen production is currently the subject in extensive scientific and technological researches toward the future of a clean-energy society. Herein, a mace-like MoS 2 /NiCo 2 S 4 hierarchical structure is designed and synthesized on carbon fiber paper via a facile hydrothermal method , and evaluated as electrocatalyst for hydrogen evolution reaction . In the MoS 2 /NiCo 2 S 4 /carbon fiber paper hierarchical structures, MoS 2 nanosheets are dispersively distributed on the surface of NiCo 2 S 4 nanowires, which provides an enlarged surface area , abundant interfaces and catalytic active sites. As for hydrogen evolution reaction , such MoS 2 /NiCo 2 S 4 /carbon fiber paper heterostructures give rise to a hydrogen evolution reaction catalytic current density of 10 mA cm −2 with a lower overpotential of 139 mV and a smaller Tafel slope of 37 mV·dec −1 than those of MoS 2 /carbon fiber paper and NiCo 2 S 4 /carbon fiber paper counterparts, exhibiting a prominent electrocatalytic performance. Moreover, the electrocatalytic properties change little after 5000 CV cycles and continual electrolysis for 12 h without obvious decay, respectively, demonstrating high durability and stability. The excellent hydrogen evolution reaction performances endow the hierarchical configuration MoS 2 /NiCo 2 S 4 /carbon fiber paper with promising alternative in HER and other related renewable energy fields.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2019
·
IF 6.393
Guojun Weng,Xinju Zhao,Jing Zhao,Jianjun Li,Jian Zhu,Junwu Zhao
The plasmonic spectral sensing method based on the etching of gold nanorods has been a powerful tool in the field of biomedical detection. Among the plasmonic etching sensors, the most popular sensing strategy is the “positive oxidative etching” plasmonic sensor that is based on plasmon blue-shifting due to nanorod shortening. In this study, we proposed a nanoplasmonic detection of dihydronicotinamide adenine dinucleotide (NADH) based on negative oxidative etching: NADH-mediated inhibition of H 2 O 2 induced gold nanorods etching. In the presence of NADH, the bromine intermediates (Br 3 − and Br 2 ) used for etching gold nanorods were reduced and consumed, inhibiting the etching rate and resulting in a small blue-shift of the longitudinal plasmon band (LPB). This shift can be utilized to sense the presence of NADH. Under the optimal reaction conditions, the LPB difference (Δλ) of etched gold nanorods and the concentration of NADH had a good linear relationship in the range of 0–4.9 × 10 −6 mol/L. The nanoplasmonic sensing showed a satisfactory preference for NADH over other common substances tested. It was successfully applied to the detection of NADH in PBS solution. This system provides a platform for the detection of targets in NADH-generated enzyme catalysis.
研究领域:
生物医学检测
·
纳米技术
·
分析化学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2016
·
IF 4.803
Zhicai Xing,Qun Li,Dewen Wang,Xiurong Yang,Xuping Sun
ABSTRACT Transition metal nitrides (TMNs) attract a lot of attention due to their excellent catalytic activities for energy related applications, although TMN catalysts developed as HER catalysts in alkaline environment are limited. Herein, we report a very simple and straightforward method to fabricate self-supported nickel nitride film on nickel foam (Ni 3 N/NF) via direct nitridation of NF under NH 3 atmosphere. The Ni 3 N/NF, as an efficient 3D hydrogen-evolving cathode, needs overpotentials of 121, 177, and 254 mV to attain current densities of 10, 20, and 100 mA cm −2 , respectively, and it maintains its catalytic activity for at least 32 h in alkaline media. Additionally, this electrode is also highly efficient under neutral and acidic conditions. The scalable fabrication approach reported here can be extended to synthesize other self-supported transition metal nitride HER cathodes.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2017
·
IF 6.035
Jinqiang Cui,Jiuqing Liu,Chunfeng He,Jie Li,Xiufeng Wu
As an important component of the lithium ion batteries, the separator has attracted much attention by researchers. In this paper, a polymer electrolyte separator based on the blended polymer of polyvinylidene fluoride and cellulose acetate was obtained via non-solvent induced phase separation (NIPS), meanwhile, the Al(OH) 3 particles was used as the addition doping into the blended polymer matrix. The structure, for example, pore size, porosity and the crystallization of the resulting separators were characterized. The thermal stability, ionic conductivity and electrochemical performance were also investigated. The results indicated that the PVDF-CA/Al(OH) 3 separator presented high porosity (68.6%), high electrolyte uptake (403.9%), especially superior thermal stability (thermal shrinkage ratio was 4.6% at 160 °C) and excellent ionic conductivity (2.85 mS cm −1 ). In addition, the rate capability (128.28 mA h g −1 at 8 C) and cycle performance (151.97 mA h g −1 after 100 cycles at 1 C) were also superior to those of the commercial polypropylene separator, demonstrating that the PVDF-CA/Al(OH) 3 separator can be a promising separator for the high-safety and high-rate dischargeable lithium ion battery.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
Molecular Catalysis
·
2024
·
IF 3.9
Jie Han,Xin Wen,Hongchao Wang,Tianren Wang,Yuzhen Sun,Luis Ricardez-Sandoval,Guoyi Bai
Selective semi-hydrogenation of alkynes plays a pivotal role in the field of chemical production but still suffers from low selectivity and catalyst stability. Herein, an aminoclay-derived nickel catalyst was constructed by replacing part of Mg 2+ by Ni 2+ in the skeleton and coordinating Ni 2+ with aminopropyl groups via a self-assembly synthetic strategy. The introduction of Ni 2+ facilitated the exfoliation of lamellar structure, resulting in highly exposed and uniformly dispersed Ni nanoparticles. The optimal catalyst showed an excellent catalytic performance with 99.9 % conversion and 98.9 % regio- selectivity to alkene ( cis / trans = 94:6) in diphenylacetylene semi-hydrogenation. Experimental data and theoretical calculations validated that the aminopropyl groups on NiMg-AC improved the activity and selectivity to alkene by tuning the adsorption/desorption energies of substrate/product. Furthermore, this non-precious metal catalyst showed stable activity and selectivity during cyclic testing, thanks to the strong interaction between Ni and the aminopropyl groups. This "self-assembly" synthetic strategy provides valuable guidance for the preparation of aminoclay-derived Ni catalysts for selective semi-hydrogenation.
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
ACTA PHYSICO-CHIMICA SINICA
·
2025
·
IF 13.5
Fanpeng Meng,Fei Zhao,Jingkai Lin,Jinsheng Zhao,Huayang Zhang,Shaobin Wang
Designing heterojunctions based on carbon nitride offers a promising pathway for enhancing photocatalytic efficiency. This study develops an all-organic S-scheme metal-free heterojunction uniquely composed of carbon nitride nanosheets (GCNNS) and a donor–acceptor conjugated polymer, poly p-aminobenzylidene-so-aniline (PASO), synthesized through a simple yet effective ball-milling technique. This heterojunction demonstrates excellent photocatalytic efficiency for hydrogen (H 2 ) evolution. The optimized GCNNS/PASO-10 sample attains an H 2 evolution rate of 10.12 mmol∙g −1 ∙h −1 , which is about 5.9 times and 19.5 times greater than those of pure GCNNS and PASO, respectively. This improvement is due to the unique interfacial bonding, increased visible-light absorption, and efficient charge carrier separation facilitated by a strong internal electric field within the S-scheme. Theoretical calculations and characterization reveal that this heterojunction’s S-scheme mechanism optimally aligns energy bands and promotes spatial charge separation, driving superior photocatalytic activity. This work presents the unique advantage of all-organic materials for heterojunction construction and provides insights into designing advanced S-scheme systems for sustainable energy conversion.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
JOURNAL OF BIOLOGICAL INORGANIC CHEMISTRY
·
2023
·Vol. 28
·期 4
·379-391
·
IF 3
Chen Chan,Tang Weikang,Chen Qinfei,Han Mengqi,Shang Qi,Liu Wenbin
Hydroxytyrosol, one of the most powerful natural antioxidants, exhibits certificated benefits for human health. In this study, a biomimetic approach to synthesize hydroxytyrosol from the hydroxylation of tyrosol was established. EDTA-Fe 2+ coordination complex served as an active center to simulate tyrosine hydroxylase. H 2 O 2 and ascorbic acid were used as oxygen donor and hydrogen donor, respectively. Hydroxy radical and singlet oxygen contributed to active species. The biomimetic system displayed analogous component, structure, and activity with TyrH. Hydroxytyrosol titer of 21.59 mM, and productivity of 9985.92 mg·L −1 ·h −1 was achieved with 100 mM tyrosol as substrate. The proposed approach provided efficient and convenient route to quickly produce high amount of hydroxytyrosol. Graphical abstract
研究领域:
生物化学
·
合成生物学
·
抗氧化研究
✓ 已验证
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2024
·
IF 4.8
Hongyan Wang,Xinyue Sun,Jingpei Cao,Yajie Tian,Bofeng Zhang
Zeolite catalysts have been widely applied in petroleum and chemical industries. Nano/hierarchical structure could improve the utilization efficiency of active sites, especially for metal species encapsulated in zeolites. However, the uniformity of zeolite surface and crystallinity would decrease, leading to low stabilization effect. Herein, we developed a seed-directed method to prepare Pd clusters (∼1.3 nm) regioselectively encapsulated in hollow polycrystalline shell of Silicalite-1 zeolite. In nitrobenzene hydrogenation reaction, the optimized Pd@S-1-hp showed a high conversion of 92.2 % at 110 °C, which is 40 % higher than that of Pd clusters in bulk zeolite. Sub-nano Pd species in polycrystalline shell could significantly shorten the diffusion length on the basis of strong microporous confinement effect. Catalytic hydrogenation activity remained stable after six cycles. This structure could be extended to heterogeneous reactions suffering from diffusion limitation.
研究领域:
化学工程
·
催化材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）