RSC Advances
·
2018
·Vol. 8
·期 66
·38003-38012
·
IF 2.936
Xiuqiong Chen,Huiqiong Yan,Wei Sun,Guangying Chen,Changjiang Yu,Wen Feng,Qiang Lin
To achieve the dispersion of the hydrophobic graphene (GR), the amphiphilic alginate caprylamide (ACA) was synthesized to fabricate electroactive Nafion/Mb–ACA–GR/CILE for the accurate determination of trichloroacetic acid (TCA). SEM observation, FT-IR and UV-Vis spectroscopic analysis indicated that ACA could tightly immobilize Mb and GR on the electrode surface by constructing biointerfaces, which not only provided Mb a suitable microenvironment to maintain its biological activity, but also shortened the distances between the active centers of Mb with carbon ionic liquid electrode (CILE), thus promoting the electron transfer rate. The electrochemical characterization of Nafion/Mb–ACA–GR/CILE showed that the direct electron transfer of Mb was realized on the modified electrode, which was attributed to the high electrical conductivity and excellent electrocatalytic activity of GR and good biocompatibility of ACA. Moreover, Nafion/Mb–ACA–GR/CILE exhibited good electrocatalytic activity towards TCA with the linear range from 2.5 to 47.3 mmol L−1 and lower KMapp value of 8.3 mmol L−1. Moreover, the modified electrode also revealed good stability, reproducibility and accurate detection of tap-water, exhibiting great potential for the applications as the third-generation electrochemical biosensors.
研究领域:
生物医学工程
·
电化学传感
·
纳米生物技术
·
分子生物学
·
分析化学
·
生物传感器
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
·
2020
·
IF 7.216
Jinxing Yu,Xiaoxiang Xu
Cr doped Ruddlesden-Popper compound Sr 2 TiO 4 has been successfully modified by fluorine to form a new compound Sr 2 Ti 0.95 Cr 0.05 O 3 F 2 . Structure analysis suggests two types of fluorine in the structure of this new compound, i.e. intralayer and interlayer F, which induce strong built-in electric field within this layered compound. The electric field stems from uneven distribution of F atoms on the two sides of perovskite layers therefore leads to charge disproportionation . DFT calculations suggest that this unique structural feature is highly beneficial for charge dissociations as it breaks the coplanar settlement of conduction band minimum and valence band maximum whilst maintains the 2D charge transportation properties. This is clearly demonstrated by the superior photocatalytic activities of Sr 2 Ti 0.95 Cr 0.05 O 3 F 2 for hydrogen production from water. Apparent quantum efficiency (AQE) as high as 1.16% at 420 ± 20 nm has been achieved which stands as the highest AQE reported on Sr 2 TiO 4 to date. Photoelectrochemical (PEC) analysis confirms improved charge separation conditions and prolonged charge lifetime.
研究领域:
材料化学
·
光催化
·
能源化学
·
物理化学
·
无机功能材料
·
太阳能转化
·
环境科学
✓ 已验证
DOI
高影响因子
EES Catalysis
·
2023
·Vol. 1
·期 3
·312-321
·
IF 0
Yiqiao Wang,Siyuan Pan,Huan Li,Dewang Li,Yong Guo,Sijia Chi,Chuannan Geng,Shichao Wu,Quan-Hong Yang
Despite lithium–air batteries having unprecedented theoretical energy supremacy, rambling Li2O2 growth typically impedes O2 diffusion and electron transfer, causing low capacity, poor charging kinetics and short cycle life. Herein, we propose synergistic catalysis in the cathode by engineering the crystal facet of Fe2O3 nanoplates and introducing a visible light-excited photochemical effect. The growth of Li2O2 is regulated with a uniform distribution, mitigating local product aggregation and thus reducing the barriers of O2 diffusion and electron transfer. The improved reaction kinetics lead to ∼420% capacity improvement, low charge potential, superior rate performance, and long-term stability (300 cycles) in actual air. We reveal a mechanism that photoelectrons around each catalyst node and the resultant homogeneous internal electric field increase charge transfer, decrease soluble intermediates, and enable high electrochemical reversibility of amorphous Li2O2 with an ordered process. This study provides inspiring insights for future research into controlling product ordering in Li–air batteries.
研究领域:
电化学
·
纳米材料科学
·
能源化学
·
催化化学
·
电池技术
✓ 已验证
DOI
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2014
·
IF 2.871
Hao Li,Qingni Yu,Bin Yang,Zhongjian Li,Lecheng Lei
Galvanostatic anodic oxidation of artificial human urine (AHU) was carried out by using boron doped diamond (BDD) and IrO 2 electrodes respectively. It was found that organic compounds in urine could be almost completely mineralized in a few hours and ammonia may be oxidized into N 2 by the electro-catalytic process. However, the oxidation processes were highly dependent on the electrode materials. On the non-active BDD electrode complete oxidation occurred, and the final oxidation products of inorganic ions, including ClO 4 − and NO 3 − , were formed. Whereas on the active IrO 2 electrode, the final products generated and left in solution were highly toxic substances, including N 2 H 4 and NO 2 − , because the oxidizing activity on the IrO 2 electrode surface is relatively low. The pH values during the degradation process were monitored and the corresponding degradation mechanisms and pathways on both electrodes are proposed based upon the measured inorganic intermediates.
研究领域:
环境科学
·
电化学
·
水处理技术
·
生物医学工程
·
分析化学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2012
·Vol. 1
·期 6
·2278-2285
·
IF 0
Jun Zhou,Ming Chen,Guowang Diao
An amphiphilic amino resorcinarene (T) was modified onto the surface of graphene oxide (GO) through covalent bond forces and non-covalent bond forces to prepare GO–T. The water-soluble graphene–T (GN–T) composite was prepared by the reduction of GO–T. Then, pre-prepared platinum nanoparticles (PtNPs) and different sized gold nanoparticles (AuNPs) could self-assemble onto the surface of GN–T through the plentiful amido groups of T to obtain GN–T–AuNPs and GN–T–PtNPs hybrid materials. It was verified that the AuNPs and PtNPs could be uniformly scattered on GN and the amount of AuNPs and PtNPs modified on GN could be adjusted by changing the weight ratio of T/GO. GN-T-PtNPs and GN-T-AuNPs composites showed the characteristics of being dispersible, stable and recyclable in water. Electrochemical results obviously revealed that GN–T–AuNPs and GN–T–PtNPs composites exhibited outstanding electrocatalytic properties.
研究领域:
纳米材料化学
·
电分析化学
·
功能复合材料
·
表面自组装
·
电催化
✓ 已验证
DOI
ELECTROCHIMICA ACTA
·
2018
·
IF 5.116
Xiaozhen Chen,Ji Qi,Pan Wang,Chuang Li,Xiao Chen,Changhai Liang
Herein, PVA-Mo 2 C/Mo 2 N nanospheres with surface roughness are synthesized via a polyvinyl alcohol (PVA) involved approach and used for hydrogen evolution reaction (HER). The average crystallite size of the PVA protected nMo 2 CN nanospheres (6.1 nm) is one third of that of the PVA-Mo 2 C/Mo 2 N without PVA protection (17.9 nm). At 10 mA cm −2 current density, the as-synthesized PVA-Mo 2 C/Mo 2 N nanospheres with surface roughness exhibit HER overpotentials of 132 mV and 142 mV with corresponding Tafel slope of 51.8 mV dec −1 and 50.4 mV dec −1 in acid and alkaline medium, respectively. This high apparent activity can be attributed to the high intrinsic activity originated from the adjacent surface active sites of Mo 2 C and Mo 2 N as well as the large ECSA of PVA-Mo 2 C/Mo 2 N nanospheres with surface roughness.
研究领域:
材料科学
·
电化学
·
纳米催化
·
能源化学
·
表面科学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2018
·
IF 5.116
Meng Wan,Han Zhu,SongGe Zhang,HaoNan Jin,YanKun Wen,LiNa Wang,Ming Zhang,MingLiang Du
Oxygen evolution reaction (OER) plays an important role in various renewable energy systems . Owing to its complex four-electron redox process , the OER process with sluggish kinetics often requires electrocatalysts to reduce the overpotential and promote the reaction rate. Herein, we have proposed an “all-in-one” strategy to synthesize mutil-elemental perovskite oxides nanofibers (NFs) with hollow and porous structures by using electrospinning technology and Ostwald ripening approach. The hollow La 0.7 Sr 0.3 Co 0.25 Mn 0.75 O 3 nanofibers (LSCM NFs) consist of large amounts of building block La 0.7 Sr 0.3 Co 0.25 Mn 0.75 O 3 nanoparticles (LSCM NPs), forming the unique architecture and the morphologies can be engineering by adjusting the calcination temperatures and the heating rates . Notably, the hollow LSCM NFs prepared at 800 °C and 10 °C min −1 demonstrated the excellent electrocatalytic performance, with overpotential of 340 mV at current density of 10 mA cm −2 and Tafel slope of 111 mV dec −1 , as well as the long-term stability in alkaline electrolyte . The hollow NFs architectures exhibited a large specific surface area , a high porosity and a large inner space, which are beneficial for the OER, reducing the overpotentials and accelerating the electrode kinetics .
研究领域:
材料化学
·
电化学
·
纳米材料科学
·
能源催化
·
功能材料
·
可再生能源
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2016
·
IF 6.333
Xiaowei Kong,Xiaoliang Zhou,Yu Tian,Xiaoyan Wu,Jun Zhang,Wei Zuo
Development of cost-effective and efficient electrochemical catalysts for the fuel cells electrode is of prime importance to emerging renewable energy technologies . Here, we report for the first time the novel La 0.9 Ca 0.1 Fe 0.9 Nb 0.1 O 3−δ (LCFNb) perovskite with good potentiality for the electrode material of the symmetrical solid oxide fuel cells (SSOFC). The Sc 0.2 Zr 0.8 O 2−δ (SSZ) electrolyte supported symmetrical cells with impregnated LCFNb and LCFNb/SDC (Ce 0.8 Sm 0.2 O 2−δ ) electrodes achieve relatively high power outputs with maximum power densities (MPDs) reaching up to 392 and 528.6 mW cm −2 at 850 °C in dry H 2 , respectively, indicating the excellent electro-catalytic activity of LCFNb towards both hydrogen oxidation and oxygen reduction. Besides, the MPDs of the symmetrical cells with LCFNb/SDC composite electrodes in CO and syngas (CO: H 2 = 1:1) are almost identical to those in H 2 , implying that LCFNb material has similar catalytic activities to carbon monoxide compared with hydrogen. High durability in both H 2 , CO and syngas during the short term stability tests for 50 h are also obtained, showing desirable structure stability, and carbon deposition resistance of LCFNb based electrodes. The present results indicate that the LCFNb perovskite with remarkable cell performance is a promising electrode material for symmetrical SOFCs.
研究领域:
材料科学
·
电化学
·
能源材料
·
燃料电池
·
催化化学
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2019
·Vol. 43
·期 44
·17502-17510
·
IF 3.069
Jie Ren,Zhenguo Wang,Yu Feng,Bangjun Guo,Ke Yu,Ziqiang Zhu
In this work, we report the first-principles investigation and synthesis method for a hollow-MoS2/C heterostructure applied to a hydrogen evolution catalytic material. First principles investigation was used to calculate the free energy of hydrogen ion adsorption at the heterostructure interface at different surface adsorption ratios. The change of the density of states before and after carbon coating proved that carbon coating improves the conductivity of the catalyst. Higher reactivity areas and higher conductivity can significantly improve hydrogen evolution catalytic performance, which is also demonstrated by electrochemical testing. Hollow-MoS2/C exhibits a low onset overpotential of 96 mV and a low Tafel slope of 67.4 mV dec−1, as well as good catalytic stability. The composite catalyst prepared by a two-step method has a larger specific surface area and a larger porosity, can significantly suppress the collapse and stacking effect caused by the electrode circulation process, and improve the cyclic reversibility and stability of the material. This work is expected to provide a meaningful reference for solving the problem of cycling performance degradation of non-precious metal-catalyzed hydrogen evolution materials.
研究领域:
材料化学
·
电化学
·
纳米材料科学
·
催化化学
·
能源材料
·
理论计算化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 86
·46208-46213
·
IF 3.708
Yuqing Lin,Lianglu Hu,Linbo Li,Keqing Wang
This study describes a facile and effective one-pot route to synthesize structurally uniform and electrochemically active nickel hydroxide–graphene nanocomposites (Ni(OH)2–GN) and investigates the electrocatalytic activity toward the oxidation of insulin. Graphene here was used to tether Ni2+ precursor onto surfaces and eventually grow Ni(OH)2 nanoparticles to form hybrid materials. The synthetic Ni(OH)2–GN nanocomposite has a uniform surface distribution, which was characterized with scanning electron microscopy (SEM). Moreover, the composition of synthetic Ni(OH)2–GN nanocomposite was characterized by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR spectra). The Ni(OH)2–GN were electrochemically treated in 0.1 M NaOH solution through cyclic voltammograms, and then gradually transited into nickel oxyhydroxide–graphene nanocomposites (NiOOH–GN), which demonstrated high catalytic activity and improved stability to insulin oxidation. The steady-state current response increases linearly with insulin concentration from 800 nM to 6400 nM with a fast response time of less than 2 s and a detection limit of 200 nM. The excellent performance of insulin sensor, including long term stability, can be ascribed to the synergistic effects of the large surface area (resulting in high loading ability), dispersing ability and conductivity of graphene and the large surface-to-volume ratio and electrocatalytic activity of Ni(OH)2 nanoparticles.
研究领域:
生物医学工程
·
电化学传感
·
纳米医学
·
糖尿病诊断
·
分子诊断
✓ 已验证
DOI
高影响因子
ADVANCED POWDER TECHNOLOGY
·
2019
·Vol. 30
·期 9
·1920-1931
·
IF 3.25
Ting Wang,Bing–rui Li,Li–guang Wu,Yu–bing Yin,Bo–qiong Jiang,Ju–qing Lou
La 3+ - or Yb 3+ -doped TiO 2 supported on the surface of reduced graphene oxide were fabricated by adsorbed-layer nanoreactor synthesis (ANS) coupling with a solvothermal treatment to extend photocatalysis application in the advanced treatment of simulated wastewater with high salt concentration. Results showed that La 3+ or Yb 3+ could distribute in the TiO 2 lattice, only in ANS preparation with graphene oxide as the carrier, to replace Ti 4+ during the solvothermal treatment, thus introducing TiO 2 mixed-crystal and heterojunction structures in the catalysts. La 3+ or Yb 3+ caused lattice distortion structures and anionic vacancies in the TiO 2 lattice. The anionic vacancies (oxygen vacancies) might generate Ti 3+ in catalysts, thus enhancing visible-light response, due to impurity levels introduced by La 3+ or Yb 3+ . As the strong adsorption capability of the catalyst for phenol was not interfered by salt ions in the simulated wastewater, the catalysts could efficiently degrade phenol. The highest removal rate of phenol was approximately 90%.
研究领域:
环境科学
·
材料化学
·
光催化
·
水处理
·
纳米材料
·
表面化学
·
环境功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED MICROBIOLOGY
·
2019
·Vol. 126
·期 1
·127-137
·
IF 2.683
Zhang H.‐L.,Zhang C.,Pei C.‐H.,Han M.‐N.,Li W.
AimsWe aimed to explore Yarrowia lipolytica carbonyl reductases as effective biocatalysts and to develop efficient asymmetric reduction systems for chiral alcohol synthesis.Methods and ResultsYarrowia lipolytica carbonyl reductase genes were obtained via homologous sequence amplification strategy. Two carbonyl reductases, YaCRI and YaCRII, were identified and characterized, and used to catalyse the conversion of 2‐hydroxyacetophenone (2‐HAP) to optically pure (S)‐1‐phenyl‐1,2‐ethanediol. Enzymatic assays revealed that YaCRI and YaCRII exhibited specific activities of 6·96 U mg−1 (99·8% e.e.) and 7·85 U mg−1 (99·9% e.e.), respectively, and showed moderate heat resistance at 40–50°C and acid tolerance at pH 5·0–6·0. An efficient whole‐cell two‐phase system was established using reductase‐expressing recombinant Escherichia coli. The conversion of 2‐HAP (20·0 g l−1) conversion with the solvent of dibutyl phthalate was approximately 70‐fold higher than in water. Furthermore, the two recombinant E. coli displayed biocatalyst activity and enantioselectivity towards several different carbonyl compounds, and E. coli BL21 (DE3)/pET‐28a‐yacrII showed a broad substrate spectrum.ConclusionsA new whole‐cell recombinant E. coli‐based bioreduction system for enantiopure alcohol synthesis with high enantioselectivity at high substrate concentrations was developed.Significance and Impact of the StudyWe proposed a promising approach for the efficient preparation of enantiopure chiral alcohols.
研究领域:
生物化学
·
生物技术
·
酶学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）