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
JOURNAL OF ALLOYS AND COMPOUNDS
·
2017
·
IF 3.133
Jing Lin,Zhanyi Cao,Lianshan Sun,Fei Liang,Limin Wang
Ti 1.4 V 0.6 Ni + x LiAlH 4 ( x = 0.5, 1, 1.5, 2, 2.5, wt.%) composites were prepared by ball-milling, and the effects of LiAlH 4 content on structure and electrochemical properties of the composites were investigated systematically. The addition of LiAlH 4 to the Ti 1.4 V 0.6 Ni alloy significantly affected the morphology and size of the composite particles . The electrochemical cycling stability and rate dischargeability of the composite electrodes benefitted from adding some LiAlH 4 ( x = 1), which however deteriorated when the LiAlH 4 content increased further. The positive effect of LiAlH 4 on the electrochemical performance of the studied alloy was caused by suppression of the dissolution of active components of the Ti 1.4 V 0.6 Ni hydrogen storage alloy.
研究领域:
材料科学
·
金属功能材料
·
能源存储
·
电化学
·
氢能技术
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
·
2022
·
IF 3.428
Baoqin Mu,Bin Li,Bin Qi
Lanthanide metal–organic framework Ln-MOFs(Ln = Sm, Dy, Dy/Sm) were synthesized by hydrothermal method at 100 °C for 12 h using lanthanide metals (Ln = Sm, Dy, Dy/Sm) as metal ion centers and 1,3,5-benzotrioic acid (H 3 BTC) as ligands. The structural characteristics of Ln(BTC)(H 2 O)·(DMF) were characterized by X-ray Diffraction(XRD), Fourier Transform Infrared Spectroscopy(FT-IR) and Thermogravimetric Analysis(TGA). Scanning electron microscopy showed that the samples showed rod-like morphology, and the fluorescence spectra showed 478 nm and 573 nm corresponding to the characteristic transitions of 4 F 9/2 → 6 H 15/2 (blue light) and 4 F 9/2 → 6 H 13/2 (yellow light) of Dy 3+ , respectively, while orange light at 600 nm and red light at 646 nm corresponded to the characteristic transitions of 4 G 5/2 → 6 H 7/2 and 4 G 5/2 → 6 H 9/2 of Sm 3+ , demonstrating that the double-doped lanthanide metal ions MOF were successfully synthesized. H 7 (P(Mo 2 O 7 ) 6 )/(Dy/Sm-MOF) was used as a sensor for the determination of H 2 PO 4 − , the results of performance evaluation showed that the electrochemical sensor showed a linear relationship between 0.01 and 0.17 mM for H 2 PO 4 − , with a detection limit of 0.005 mM/L, good stability and reproducibility, which opened up a new way for the detection of orthophosphate dihydrogen.
研究领域:
分析化学
·
材料科学
·
电化学
·
无机化学
·
传感器技术
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Hongyuan Qin,Jiawei Huang,Xueli Zhang,Ling Yu,Yang Yu
In this study, lanthanum hydroxide adsorbent was synthesized through a simple hydrothermal method and applied for removing phosphate from water. The optimal adsorbent was obtained at the La/OH molar ratio of 4:1. The adsorbent showed rapid adsorption of phosphate within the first 4 h in which approximately 84% of the equilibrium adsorption capacity can be achieved. The phosphate uptake was highly dependent on solution pH. The better fit of the Langmuir isotherm model to experimental data indicated that the monolayer adsorption occurred and the maximum adsorption capacity of 193.9 mg/g was accomplished at pH 7.0. The presence of fluoride could significantly retard the uptake of phosphate. X-ray photoelectron spectroscopy analysis indicated that hydroxyl groups on the adsorbent surface played the most key role in the adsorption. The phosphate ions were adsorbed on the adsorbent through the formation of inner-sphere complexes.
研究领域:
环境化学
·
纳米材料科学
·
水污染控制
·
表面化学
·
吸附科学
✓ 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
EUROPEAN POLYMER JOURNAL
·
2013
·Vol. 49
·期 6
·1731-1741
·
IF 2.562
Wenwen Yu,Dezhi Zhang,Miao Du,Qiang Zheng
A series of novel polyurethane (PU)/epoxy resin (EP) graft interpenetrating polymer network (IPN) composites with graded length side chains were prepared from toluene diisocyanate (TDI), polytetrahydrofuran glycol (PTMG), EP, trimethylolpropane (TMP), and diol chain extenders. The effects of the side chain lengths, content, and groups on the damping properties and mechanical properties were investigated. Two damping peaks were observed in the PU/EP IPN system, indicating that the peak damping factor (tan δ ) increased with increased side chain length at low temperatures. The introduction of an apolar side chain slightly narrowed the damping range. However, the side chain carrying polar groups broadened the damping temperature range. The strong H-bond interaction between the ester group of side chain and the N H of hard segments in PU was believed to favor microphase separation to form a larger-sized domain and induce the appearance of the relaxation peak at high temperatures. Consequently, the effective damping temperature range was broadened. The side chain content tethered in the hard segment remarkably influenced the damping properties of PU/EP IPNs both at low and high temperatures. The width and intensity of the tan δ peaks of PU/EP IPNs increased with increased side chain content. The mechanical properties (tensile strength and elongation at break) were significantly affected by the side chain content. Thus, an important method of improving the mechanical damping of elastomers by controlling the side chain molecular structure was established.
研究领域:
高分子材料科学
·
功能高分子
·
阻尼材料
·
复合材料
·
聚合物共混物
·
材料力学
✓ 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
·
油脂化学
·
生物基材料
·
绿色化工
·
天然产物转化
✓ 已验证
DOI
高影响因子
Small
·
2022
·Vol. 18
·期 47
·2203588
·
IF 15.153
Jinli Fan,Chengyu Fu,Rikai Liang,Haiyang Lv,Chaosong Fang,Yanhui Guo,Weiju Hao
Mild construction of highly efficient and durable practical electrodes for overall water splitting (OWS) at industrial-grade current density is currently a significant challenge. Herein, metal–organic framework (MOF) materials are grown in situ on the surface of carbon cloth (CC) at 25 °C, and quickly “interspersed” by cobalt–boron (Co–B) via electroless plating for 30 min to obtain a highly efficient and stable CoB@MOF@CC self-supporting electrode. Owing to the large specific surface area, abundant active sites, and porous structure, the MOF-based CC modified by bamboo leaf-like ultrathin CoB has remarkable electrochemical catalysis efficiency. The CoB@MOF@CC electrode exhibits excellent performance during the hydrogen evolution reaction (η 10 = 57 mV, η 500 = 266 mV) and oxygen evolution reaction (η 10 = 209 mV, η 500 = 423 mV) in alkaline simulated seawater, and is durable for 2500 h at 500 mA cm −2 . The OWS performance is obviously enhanced by employing the prepared electrode, which only requires 1.49 V to achieve 10 mA cm −2 and is durable for over 360 h at industrial-grade current densities in alkaline high-salt, real seawater, rainwater, and urea electrolytes.
研究领域:
材料科学
·
电化学
·
能量转换
·
纳米技术
·
化学工程
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2015
·
IF 2.587
Xia Zhang,Qiuxiang Yin,Wei Du,Junbo Gong,Ying Bao,Meijing Zhang,Baohong Hou,Hongxun Hao
The crystal structures of monohydrate and anhydrous substance were determined from the single crystals for the first time. The phase transformation between anhydrate and monohydrate of sodium dehydroacetate was in situ investigated by using Raman spectroscopy. The mechanism of the phase transformation was proposed. The results showed that the monohydrate crystalline phase of sodium dehydroacetate can transform to anhydrous phase through solid–solid transformation upon heating or solution-mediated phase transformation. From powder X-ray diffraction (PXRD) patterns and thermal gravimetric analysis (TGA) data, it was found that the anhydrous crystals obtained by these two methods are the same in structure. However, the scanning electron microscopy (SEM) results revealed that the surface of the anhydrous sodium dehydroacetate crystals obtained by high-temperature dehydration was much rougher than that obtained by solution-mediated phase transformation. Furthermore, the dynamic vapor sorption (DVS) results showed that the anhydrous crystals with rough surface had faster hydration rate than the anhydrous crystals with smooth surface when increasing humidity. The reasons behind these phenomena were discussed.
研究领域:
药物化学
·
晶体学
·
药剂学
·
材料科学
·
物理化学
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2022
·
IF 4.326
Chen Chen,Yu Liang,Qiong Tang,Dong Li,Lei Liu,Jinxiang Dong
The hydrogenolysis of glycerol to 1,3-propanediol has an important industrial value but remains a great challenge. Herein, a tungsten oxide hydrate (WO3·H2O) containing Brønsted acid sites and surface oxygen vacancies was in situ grown on the surface of alumina. The coordination chemistry of WO3 on the carrier contributes to the extremely dispersed platinum and the excellent acidic property, and much more Pt–O–W interfaces are created. The synthetic Pt/H–WO3/γ-Al2O3 catalyst exhibited much higher catalytic performance for glycerol hydrogenolysis than Pt/C–WO3/γ-Al2O3, in which C–WO3/γ-Al2O3 was routinely prepared by calcining the tungsten precursor (AMT) pre-impregnated on γ-Al2O3. The success for this strategy lies in the pre-control toward the state of WO3 on the support, and several characterization techniques were performed to reveal the structure–property relationship.
研究领域:
催化化学
·
材料化学
·
工业化学
·
应用化学
·
能源化学
✓ 已验证
DOI
高影响因子
Advanced Materials Interfaces
·
2020
·Vol. 7
·期 12
·2000010
·
IF 4.948
Puttaswamy Madhusudan,Run Shi,Bananakere Nanjegowda Chandrashekar,Shengling Xiang,Ankanahalli Shankaregowda Smitha,Weijun Wang,Haichao Zhang,Xian Zhang,Abbas Amini,Chun Cheng
Solar water splitting using semiconductor photocatalysts is considered to be one of the economical and significant techniques for hydrogen evolution. In this study, graphene–Zn x Cd 1− x S (ZCS) heterojunction is fabricated by hydrothermal method followed by simple photodeposition of ultrathin few layers of molybdenum sulfide (MoS 2 ) nanosheets. The results show that compared with pristine ZCS and 1 wt% graphene mixed ZCS photocatalysts, the 1 wt% graphene and 1 wt% MoS 2 photodeposited ZCS composited sample shows 39.5 mmol h −1 g −1 hydrogen production activity, which is 6.9 and 1.9 times significantly higher, respectively, with an apparent quantum yield of 53% at 420 nm visible light is recorded. The improved photocatalytic activity can be attributed to the formation of heterostructure interface between p-type MoS 2 nanosheets with n-type ZCS host, which allows for the faster transfer of the photogenerated electrons and thus significantly promotes the separation of photogenerated charge carriers.
研究领域:
材料化学
·
光催化
·
能源科学
·
纳米材料
·
半导体物理
·
可持续能源
·
表面科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）