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
Small
·
2018
·Vol. 14
·期 31
·1801680
·
IF 9.598
Jiangjiang Zhang,Wenshu Zheng,Xingyu Jiang
Chemical regulation of enzyme-mimic activity of nanomaterials is challenging because it requires a precise understanding of the surface chemistry and mechanism, and rationally designed applications. Herein, Ag + -gated peroxidase activity is demonstrated by successfully modulating surface chemistry of cetyltrimethylammonium bromide-capped gold nanoparticles (CTAB-AuNPs). A surface blocking effect of long-chain molecules on surfaces of AuNPs that inhibit peroxidase activity of AuNPs is found. Ag + ions can selectively bind on the surfaces of AuNPs and competitively destroy CTAB membrane forming Ag + @CTAB-AuNPs complexes to result in enhanced peroxidase activity. Ag + @CTAB-AuNPs show the highest peroxidase activity compared to similar-sized citrate-capped and ascorbic acid-capped AuNPs. Ag + @CTAB-AuNPs can potentially develop into analyte-responsive systems and exhibit advantages in the optical sensing field. For example, the Ag + @CTAB-AuNPs system shows an enhanced sensitivity and selectivity for acetylcholinesterase activity sensing compared to other methods.
研究领域:
纳米生物技术
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分析化学
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酶学
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生物传感器
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分子诊断
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转化医学
·
药物代谢
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2013
·Vol. 34
·期 12
·2161-2166
·
IF 1.304
Mingming Zhang,Manman Jiang,Changhai Liang
A basic anion exchange resin , Amberlite IRA-900, was loaded with Pd(C 3 H 5 )(C 5 H 5 ) by an easy metal-organic chemical vapor deposition (MOCVD) approach to give Pd@IRA-900 catalyst after reduction at room temperature . Ultraviolet-Visible spectroscopy results showed a red shift of the absorption peak of Pd 2+ after the Pd precursor was loaded on the resin, indicating that a chemical reaction occurred between the precursor and the support. Pd nanoparticles with 2.6 nm of average size were well dispersed on the support. The Pd@IRA-900 catalyst showed high activity for different kinds of aryl halides in Suzuki-Miyaura coupling reactions under mild and aerobic conditions. Excellent recyclability of Pd@IRA-900 catalyst was also observed in the Suzuki-Miyaura coupling reaction of iodobenzene and phenylboronic acid . A bifunctional catalyst Pd@IRA-900(OH) was synthesized by pretreating the ion exchange resin support with NaOH before Pd loading, which successfully catalyzed the Suzuki-Miyaura reaction of iodobenzene and phenylboronic acid without base under aerobic conditions.
研究领域:
催化化学
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有机合成
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材料化学
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绿色化学
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纳米催化
✓ 已验证
DOI
高影响因子
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
·
2015
·Vol. 94
·期 3
·424-429
·
IF 1.231
Xia Gui,Ying Ding,Zhi Yun
An integrated approach was developed for preparing epoxy fatty acid methyl esters (EFAMEs) from cottonseed using a two-phase solvent extraction (TPSE) process followed by sequential base-catalyzed transesterification and epoxidation reactions. The TPSE process was performed to achieve simultaneous production of high-quality crude cottonseed oil and nontoxic cottonseed meal. The base-catalyzed transesterification of the cottonseed oil proceeded smoothly at 30 °C over 2 h to provide a high yield of fatty acid methyl esters (FAMEs). Subsequent epoxidation of the unsaturated FAMEs using petroleum ether as a non-polar solvent, H 3 PO 4 as a catalyst, 0.3 g/g H 2 O 2 as an oxygen donor, and HCOOH as an oxygen carrier gave the corresponding EFAMEs with a conversion to oxirane of 0.85 g/g. The order of effectiveness of catalysts was found to be H 3 PO 4 > TiO 2 > H 2 SO 4 > strong-acid cation exchange resin. The bio-based integrated process and new methods for the preparation of modified EFAMEs show great promise for comprehensive development and commercial applications of cottonseed with fewer steps and lower cost.
研究领域:
应用化学
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油脂化学
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生物基材料
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绿色化工
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天然产物转化
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Cuiyun Liu,Menghui Zhao,Hui Liu,Jun Zhang,Zihao Hu,Yuhan Zhang,Xinchang Pang
Tartrazine (TAR), widely used as a synthetic food dye, and U(VI), primarily originating from nuclear industry effluents, pose serious environmental and health risks due to their toxicity and persistence. However, many existing adsorbents suffer from low capacity, poor stability, and limited reusability. Herein, A bio-based aerogel adsorbent (NDC) with a stable three-dimensional porous network structure was prepared through a Schiff base reaction between dialdehyde-functionalized nanocellulose fibrils (DNCFs), chitosan (CS), and aminated metal–organic frameworks (MOFs). The synergistic effect of MOFs , DNCFs, and CS resulted in high adsorption capacities of 689.66 mg/g for TAR and 285.72 mg/g for U(VI) at a temperature of 303 K, respectively. Additionally, the Schiff base chemical bonds firmly anchored the MOFs in the NDC aerogel, providing a compressive strength of 547.4 kPa at 70 % strain. Furthermore, due to the antibacterial properties of the amino groups on CS and MOFs, the NDC aerogel demonstrated excellent anti-biofouling performance. The results suggest that bio-based NDC aerogel is an efficient and prospective for the removal of TAR and U(VI) from wastewater as an adsorbent.
研究领域:
环境科学
·
材料科学
·
纳米技术
·
污染控制
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核废料处理
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水处理
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生物医学工程
·
绿色化学
✓ 已验证
DOI
高影响因子
CELLULOSE
·
2019
·Vol. 26
·期 12
·7355-7370
·
IF 3.917
Dong Yahao,Bi Jiajun,Zhu Dajian,Meng Di,Ming Shujun,Guo Wen,Chen Zhen,Liu Qian,Guo Lei,Li Tao
Due to their eco-friendly nature, polysaccharides are desirable supporting materials in organic transformations. Nevertheless, as is the case for other supports, polysaccharides have to face the issue of seeking more binding sites via multifunctional structures to capture metal species in the catalyst, which enhance stability and promote catalytic performance in aforementioned process. In this paper, an environmentally-friendly and multifunctional cellulose supported Pd(II)-Schiff base complex is fabricated and applied in the formation of different biaryls under mild ambient conditions. The results of thermal analysis reveal that the composite has high thermal stability. The as-prepared catalyst demonstrates to be a robust and efficient catalyst with more than 90% yields in H 2 O: EtOH (1:1) at 70 °C by using 0.30 mol% of catalyst under air towards the coupling of various substituted aryl halides and phenylboronic acids. Moreover, identified by ICP-OES analysis, the green Pd(II) catalyst displays higher metal content (1.93%) in comparison with the direct deposition of Pd particles on cellulose (0.93%), and prevents the metal leaching (< 1%) via the coordination interaction of multiple capturing sites (–OH, Schiff base and pyridyl moieties) with palladium. The resultant catalyst is characterized by FT-IR, TGA, XRD, SEM, TEM, XPS, CP/MAS 13 C-NMR, and ICP-OES examination. Also, this green catalyst is able to be retrieved in five cycles with simple centrifugation. Notably, we propose a plausible multifunctional catalyst complex. The present study offers a novel and effective supported catalyst, which broadens the contributions of polysaccharides in green catalysis. Graphic abstract
研究领域:
高分子化学
·
绿色化学
·
有机催化
·
材料化学
·
环境友好材料
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2017
·
IF 2.843
Wei Fang,Sen Yang,Tong-Qi Yuan,Adam Charlton,Run-Cang Sun
Anionic, cationic, and nonionic surfactants with varying concentrations (0.2–1.2%) were introduced to neutralize beads on lignin nanofibers by decreasing the surface tension of spinning dopes. The surfactants used in this work were sodium dodecyl sulfate (SDS), N,N,N-trimethyl-1-dodecanaminium bromide (DTAB), and Triton X-100 (TX-100). The effects of viscosity, rheological properties, surface tension, and conductivity of the solutions on the morphology and physicochemical performances of fibers were investigated. As expected, the presence of certain amounts of surfactants eliminated the beads and resulted in the formation of smooth and bead-free fibers with small diameters. Furthermore, the gravimetric capacitance of the carbon mat with 1% SDS was slightly improved from 66.3 to 80.7 F g–1. The results suggested that the surfactants benefit from the electrospinning of lignin and allow for the control over nanofiber morphology without compromising their performance as supercapacitor electrodes.
研究领域:
高分子材料
·
纳米纤维技术
·
能源材料
·
电化学
·
表面科学
·
生物基材料
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2016
·
IF 4.758
Pengjuan Ni,Yujing Sun,Haichao Dai,Wangdong Lu,Shu Jiang,Yilin Wang,Zhen Li,Zhuang Li
In this paper, a novel, convenient and sensitive colorimetric assay for acetylcholinesterase (AChE) activity and its inhibitor screening is successfully proposed based on the peroxidase-like activity of Prussian blue nanocubes (PB NCs). PB NCs can catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) by H 2 O 2 to develop a blue color and an absorption peak centered at 652 nm. AChE mediates the hydrolysis of acetylthiocholine (ATCh) to yield a reducing agent thiocholine (TCh) that cause the reduction of oxidized TMB and it can also chelate with Fe 3+ , both of which result in a blue color fading and a decrease of the absorbance. The generation of TCh is inhibited and the absorbance intensity is recovered after the introduction of AChE inhibitor. Consequently, the assay is also utilized in AChE inhibitor screening. The PB NCs-H 2 O 2 -TMB based platform is highly sensitive for AChE activity sensing with a low detection limit of 0.04 mU/mL. In addition, this assay has great potential in discriminatively determining AChE over other enzymes. The proposed method is fairly novel, simple and sensitive, which may pave the way for the detection of other hydrolytic enzyme activities with properly selected substrates.
研究领域:
生物分析化学
·
酶学
·
纳米生物技术
·
药物筛选
·
分子诊断
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Yue Sun,Deqiang Yin,Jintao Duan,Rajendra Prasad Singh
Weak base anion exchangers are promising for decontamination of aromatic ionizable organic compounds (AIOCs) from industrial wastewaters. However, the effect of alkyl chain length of an amine functional group of resins on decontamination process has rarely been clarified to the best of our knowledge. In the present study, a commercially available weak base anion exchange resin D301 and two newly synthesized ones AEC-2 and AEC-4 with a varying alkyl chain length of amine functional groups (derived from dimethylamine, diethylamine and dibutylamine, respectively) were used for adsorption of ^-naphthalene sulfonic acid (NSA). Adsorption isotherms and influence of solution pH, temperature, time and coexisting competitive inorganic salt (Na 2 SO 4 ) on adsorption behavior were investigated and the column adsorption-regeneration tests were carried out. Results showed that adsorption selectivity for NSA over sulfate increased with increasing the alkyl chain length in the high saline water. But the sorption velocity decreased to a moderate extent with increasing the alkyl chain length. Thermodynamic parameters indicate that adsorption is an exothermic and spontaneous process, and NSA adsorption onto AEC-4 is an enthalpy-driven process, while that of D301 as well as AEC-2 is an enthalpy- and entropy-driven simultaneous process. Further, results of column tests validate long alkyl chain enhancing the sorption selective for NSA and suggest the sorption process can be reversible.
研究领域:
环境工程
·
水处理化学
·
吸附科学
·
功能高分子材料
·
工业废水治理
✓ 已验证
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2018
·Vol. 20
·期 44
·28068-28074
·
IF 3.906
Yue Yu,Sushu Wan,Daocheng Hong,Yuxi Tian
Post-fabrication defect passivation of organometal halide perovskites has become an efficient way to improve their photophysical properties, but the underlying mechanisms are still in debate. In this work, we used p-benzoquinone (p-BQ) to generate surface defects on methylammonium lead triiodide perovskite (MAPbI3), and found that a Usanovich acid–base (O2, acetone or acetonitrile) treatment can effectively passivate those defects and lead to photoluminescence (PL) enhancement. The passivation effect arose from partial neutralization of defect charges via electron transfer between passivation reagents and relevant defects. O2 accepted photo-generated electrons, formed negatively charged oxygen species and attached to the I vacancy site to reduce its PL quenching efficiency by neutralising the defects positive charge. Likewise, acetone accepted photo-generated holes, formed positively charged species and partially neutralised the defects negative charge. The reduced trapping ability of defects caused PL enhancement. In addition, the observed photo-catalysed oxidation of acetone by O2 on the crystal surface supported the single electron transfer mechanism, and showed the potential of MAPbI3 as a photo-catalyst.
研究领域:
材料科学
·
光物理学
·
半导体材料
·
表面化学
·
光电功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2022
·
IF 9.794
Zhengjian Li,Sian Chen,Liting Cui,Haining Wang,Shanfu Lu,Yan Xiang
The acidic-alkaline interface of a bipolar membrane fuel cell (BPMFC) is the place to generate water, which significantly affect the output performance of BPMFC by regulating the water distribution due to the ion conductivity and oxygen reduction reaction (ORR) kinetics in cathode. To investigate the influence of water diffusivity ( D w ) on the water distribution, four alkaline polymer electrolytes with different D w is selected as anion exchange membrane or alkaline electrolyte ionomer to assemble BPMFCs. A combined experimental and simulated study reveals the positive correlation relationship of D w to the water distribution and performance of BPMFC. By increasing the D w of the alkaline polymer electrolytes, the interfacial-generated water amount can be increased and promptly transport to the cathode, thereby satisfying the ion conductivity and increasing the ORR kinetics, and breakthrough the peak power density of the BPMFC with 1.06 W cm −2 without humidification .
研究领域:
电化学
·
能源材料
·
燃料电池
·
高分子科学
·
界面科学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2019
·Vol. 44
·期 12
·6148-6159
·
IF 4.084
Xiaoyu Zhang,Shiyuan Yu,Qian Zhu,Lianhua Zhao
The novel SP/IL/AMS composite membrane doped with amino-functionalized mesoporous silica (AMS) was successfully prepared. Sulfonated poly ether ether ketone (SPEEK, SP) was used as the polymer matrix and the ionic liquid (IL) was N -ethylimidazolium trifluoromethanesulfonate (EIm[Tfo]). Its properties were compared with SP/IL/NMS composite membrane doped with non-functionalized mesoporous silica (NMS). Fourier transform infrared spectroscopy (FT-IR) analysis indicated that the components in the composite membrane were bound by intermolecular forces. In addition, an acid-base interaction was formed between -NH 2 in AMS and -SO 3 H in SPEEK. The acid-base pair is beneficial to proton conduction. The anhydrous proton conductivity of SP/IL/3-AMS-7.5 composite membrane is about 4 times higher than that of the SP/IL/NMS-7.5. In addition, the good interfacial compatibility between AMS and polymer matrix is conducive for creation continuous proton transfer channel. Thermogravimetric analysis (TG) showed that all composite membranes were stable at 270 °C. The leaching of IL data indicated that IL can be effectively retained due to the presence of -OH and -NH 2 on the NMS and AMS surfaces. The SP/IL/AMS composite membrane could be used in proton exchange membrane fuel cells under medium temperature and anhydrous conditions.
研究领域:
材料科学
·
高分子化学
·
能源材料
·
燃料电池
·
膜科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）