Science China-Materials
·
2021
·Vol. 65
·期 3
·721-731
·
IF 8.273
Xu Hui,Jin Meng,Geng Jing,Zhang Shengbo,Zhang Haimin
The decentralized production of H 2 O 2 via a two-electron oxygen reduction reaction (2e − ORR) has emerged as a promising alternative to the energy-intensive anthraquinone (AQ) process. However, its practical application requires 2e − ORR electrocatalysts with high activity and selectivity. Herein, we report the synthesis of metallic Ni nanoparticles anchored on bacterial cellulose-derived carbon fibers (Ni-NPs/BCCF) via a facile impregnation-pyrolysis method as efficient electrocatalysts for 2e − ORR to H 2 O 2 . By tuning the amount of Ni precursor, the best electrocatalytic performance toward 2e − ORR was achieved for Ni-NPs/BCCF-20.7, affording a high H 2 O 2 selectivity of ∼90% and an onset potential of 0.75 V vs. reversible hydrogen electrode (RHE) in an alkaline electrolyte. Ni-NPs/BCCF-20.7 achieved the largest H 2 O 2 yield rate of 162.7 ± 13.7 mmol g cat −1 h −1 and the highest Faradaic efficiency of 93.9% ± 4.2% at 0.2 and 0.5 V vs. RHE from the bulk ORR system, respectively. Theoretical calculations revealed the more favorable “end-on” adsorption configuration of molecular oxygen on the exposed Ni(111) plane, which can effectively suppress the O-O bond dissociation, resulting in high selectivity for H 2 O 2 generation.
研究领域:
材料化学
·
电化学
·
纳米催化
·
能源科学
·
环境工程
✓ 已验证
DOI
高影响因子
ChemSusChem
·
2019
·Vol. 12
·期 4
·858-865
·
IF 7.804
Xinxin Li,Qingshan Zhao,Xiang Feng,Lei Pan,Zhuangzhuang Wu,Xiaocui Wu,Tianwen Ma,Jialiang Liu,Yuanyuan Pan,Yan Song,Mingbo Wu
Graphical Nitrogen-doped graphene nanoshells supporting palladium nanoparticles (Pd/N-GNS) have been developed as a superior catalyst for the N -allylation reaction. Experimental results and DFT calculations reveal strong metal–support interactions between the pyridinic N and palladium species, which significantly boost the catalytic efficiency and stability of the catalyst. In this study, nitrogen-doped graphene nanoshells (N-GNS) were developed to support palladium nanoparticles (Pd/N-GNS) as an efficient and recyclable catalyst for the N -allylation reaction. N-GNS was synthesized through a facile hard-template method by using petroleum asphalt, followed by nitrogen doping by thermal annealing with urea, the contents and species of which could be altered by the calcination temperature. Palladium nanoparticles (Pd NPs) with an average diameter of 3.3 nm were homogeneously deposited onto the N-GNS support through a mild solvent-growth approach. The Pd/N-GNS exhibited a superior activity towards the N -allylation reaction, 6-fold higher than that of the pristine graphene nanoshells supporting the palladium catalyst. The Pd/N-GNS could be recycled several times without activity deterioration and metal leaching. The catalytic activity showed a linear correlation relationship with the pyridinic N content. Experimental and theoretical studies reveal strong metal–support interactions between the pyridinic N and palladium species, which can downsize the Pd NPs, modulate the electronic properties, and promote the adsorption of reactant, thereby significantly boosting the catalytic efficiency and stability for the N -allylation process. The present work could help unravel the roles of nitrogen-doped carbon supports and provides a feasible strategy to rationally design superior palladium catalysts for chemical transformations.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Xijun Wei,Yanhong Li,Huarong Peng,Ming Zhou,Yingqing Ou,Yibin Yang,Yunhuai Zhang,Peng Xiao
In this work, hollow CoS nanobox (noted as HCSN) have been successfully synthesized via annealing and hydrothermal process from zeolitic imidazolate framework (ZIF-67) template. When tested as positive electrode materials in alkaline aqueous electrolyte, it shows high specific capacitance of 720 F g −1 at a current density of 1 A g −1 , good rate capability (82.1%) and good cycling stability with 86.4% capacitance retention over 10,000 cycles at 10 A g −1 . To further demonstrate the advantages of our ZIF-67 derived materials, asymmetric energy storage device was assembled (HCSN//NC), where the as-prepared HCSN was employed as the anode and ZIF-67-derived nanoporous carbon (noted as NC) as the cathode. This device achieves high energy density (80 Wh kg −1 at a specific power density of 882 W kg −1 ), good rate capability (53.3 Wh kg −1 even at a specific power density of 7.9 kW kg −1 ) and long-term stability up to 10,000 cycles. More importantly, it could simultaneously light up 12 LEDs in parallel, demonstrating its potential in practical applications.
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
功能材料
·
应用物理
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
·
2018
·
IF 2.207
Hongyu Shi,Na Li,Zhixia Sun,Tianqi Wang,Lin Xu
TiO 2 nanoparticles are commonly used as versatile precursors to make functional nanocomposite materials. However, the surface defects at grain boundaries of TiO 2 nanoparticles significantly affect the photoelectric properties of TiO 2 nanomaterials . In this work, we firstly prepared nanocomposites of TiO 2 and polyoxometalates (POMs) in which different POMs, including titanium-substituted POMs K 5 [PW 11 TiO 40 ] and K 7 [PW 10 Ti 2 O 40 ], are incorporated with TiO 2 nanoparticles so as to make an interface modification on grain boundaries of TiO 2 nanoparticles. Then the photoconductivities of the TiO 2 /POM nanocomposites were investigated through measurement of photocurrent responses, current-voltage curves, Mott-Schottky plots and surface photocurrent spectra. Compared with pure TiO 2 nanoparticles, TiO 2 /POM nanocomposites exhibit superior photoelectric properties, benefitting from the interface modification from different POMs. The gas sensing performance for acetone was also explored by use of the as-prepared photoconductive devices, and TiO 2 /PW 11 Ti exhibited a high gas sensing performance.
研究领域:
材料科学
·
纳米科技
·
半导体物理
·
传感器技术
·
光电子学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2013
·Vol. 38
·期 25
·10932-10938
·
IF 3.548
H. Wang,J. Zhang,J.W. Liu,L.Z. Ouyang,M. Zhu
In this study, alkali hydroxides (NaOH, LiOH, KOH) were attempted as new-type catalytic additives to improve the hydrogen storage properties of MgH 2 by ball milling . It is shown that the additives readily react with the MgH 2 to form perovskite-structured NaMgH 3 and KMgH 3 , but not the LiMgH 3 . Although the in-situ formed perovskite hydrides remain stable during hydriding/dehydriding cycles, both NaMgH 3 and KMgH 3 show predominant catalytic role on the hydriding and dehydriding of MgH 2 . In contrast, the LiOH modified MgH 2 presents much inferior sorption kinetics because of the absence of LiMgH 3 . The catalytic mechanism of perovskite hydrides can be explained by the high hydrogen mobility in the perovskite structure . This study shows that such cheap hydroxides could be used as efficient catalysts to improve the hydrogen storage properties of high-capacity metal hydrides and complex hydrides .
研究领域:
材料科学
·
无机化学
·
能源化学
·
氢能存储
·
金属氢化物
·
固态储氢
·
催化化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2017
·Vol. 52
·期 19
·11701-11714
·
IF 2.599
Wei Xiuzhen,Hong Jialiang,Zhu Shuangshuang,Chen Jinyuan,Lv Bosheng
Polyethyleneimine (PEI) of various molecular weights and trimesoyl chloride (TMC) were utilized to prepare composite nanofiltration (NF) membranes via interfacial polymerization. The changes in the surface structure and chemical composition of the prepared membranes were evaluated using SEM, ATR-FTIR, XPS and surface potential measurements. The pure-water flux and rejection rates of the inorganic salts (MgCl 2 , MgSO 4 , Na 2 SO 4 and NaCl) through the resultant NF membranes were also investigated. The results showed that the performance of the composite NF membranes was significantly affected by the molecular weight of the PEI. Notably, the permeate flux and rejection rate of the NF membranes increased with the PEI molecular weight. In addition, when the NF membranes were used to treat actual wastewater from the electroplating industry, the NF membranes presented high-efficiency separation properties for heavy metal ions. The rejection rates of the NF membranes at 0.4 MPa for chromium, nickel, zinc and copper ions reached 92.6, 89.6, 89.2 and 86.3%, respectively.
研究领域:
材料科学
·
膜分离技术
·
环境工程
·
高分子化学
·
水处理
✓ 已验证
DOI
高影响因子
DIAMOND AND RELATED MATERIALS
·
2020
·
IF 2.65
Xiao-yu Zhang,Min Xu,Sheng-zhu Cao,Wen-bo Chen,Wen-yao Yang,Qin-yu Yang
Diamond/copper composite has been considered as one of the next generation thermal management materials. Interfacial modification is an essential means of ameliorating interface wettability and bonding of diamond/copper composite for improving its thermal conductivity . In the present work, Diamond/copper composite was manufactured by using spark plasma sintering (SPS) technology with 60% volume fraction of diamond mixed with 40% volume fraction of copper power, chromium powder (0.7 wt%) and scandium oxide powder (0.21 wt%). A series of material analysis methods were used to characterize the microstructure, interfacial layer , phase compositions and distributions of Diamond/copper composite. The total and partial electron density of states (DOS) for Diamond-Cr-Sc 2 O 3 interfacial model was investigated by means of first-principles calculations from CASTEP modules. The results showed Sc 2 O 3 made a 5–20 nm well-arranged and uniformly distributed interfacial chromium carbide layer in the interface region, which played a critical role in increasing the amount of reactive interfacial bonding and decreasing defect. The addition of Sc 2 O 3 brought the increasing number of heat transfer carriers at the interface and made the interface energy system more stable. The obtained diamond/copper composite exhibited that the wettability between diamond particles and copper was effectively improved. The thermal conductivity of diamond/copper is 872 W/(m·K) and the possible reasons for doping rare-earths Sc 2 O 3 to improve the thermal conductivity were discussed.
研究领域:
材料科学
·
复合材料工程
·
界面科学
·
热管理材料
·
粉末冶金
·
计算材料学
✓ 已验证
DOI
高影响因子
Small
·
2019
·Vol. 15
·期 7
·1804974
·
IF 10.856
Na Li,Pingping Wei,Linan Yu,Junyi Ji,Jiupeng Zhao,Chuanbo Gao,Yao Li,Yadong Yin
The dynamic optical switch of plasmonic nanostructures is highly desirable due to its promising applications in many smart optical devices. To address the challenges in the reversibility and transmittance contrast of the plasmonic electrochromic devices, here, a strategy is reported to fabricate color switchable electrochromic films through electro-responsive dissolution and deposition of Ag on predefined hollow shells of Au/Ag alloy. Using the hollow Au/Ag alloy nanostructures as stable seeds for site-specific deposition of Ag, elimination of the random self-nucleation events is enabled and optimal reversibility in color switching is allowed. The hollow structure further enables excellent transmittance contrast between the bleached and colored states. With its additional advantages such as the convenience for preparation, high sensitivity, and field-tunable optical property, it is believed that this new electrochromic film represents a unique platform for designing novel smart optical devices.
研究领域:
材料科学
·
纳米科技
·
光学工程
·
功能材料
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF SUPERCRITICAL FLUIDS
·
2024
·
IF 3.4
Jianqiao Yang,Yining Ding,Fen Zhao,Shuzhong Wang,Yanhui Li,Donghai Xu
In this study, a Cr coating was fabricated on Ni-based alloys to prevent under-deposit corrosion. The effect of salt deposition on the structural integrity of the Cr coating in SCW environment with/without oxygen was investigated. Results show that the Cr coating kept its integrity after exposure in SCW environment, successfully avoided the metallic ions leaching from Ni-based alloys. The structure of the oxide layer after exposure is a thin Fe 2 O 3 or FeCr 2 O 4 layer and a Cr 2 O 3 layer. The oxidation rate of the Cr coating decreased to one third of the sample after exposure in the same environment without salt deposit layer, indicating that the inward mass-transfer of oxygen to the alloy surface was inhibited by the salt deposit layer. The volume expansion of the sample due to the growth of Cr oxide layer was restrained by the salt deposit layer, forming a growth stress in the coating.
研究领域:
材料科学
·
腐蚀科学
·
高温材料学
·
表面工程
·
能源材料
·
化学工程
✓ 已验证
DOI
高影响因子
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
Journal of Materials Chemistry A
·
2023
·Vol. 11
·期 36
·19536-19545
·
IF 11.9
Gege Wang,Feifan Zhang,Caiyu Ma,Jianhua Yang,Xiaowei Chi,Yu Liu
Aqueous zinc metal batteries (AZMBs) as one of the next-generation energy storage technologies have attracted both academic and industrial attention due to their high safety, low cost, and high specific energy, yet are facing interfacial challenges at the electrolyte/anode interface, e.g. uneven physical diffusion of Zn2+ flux, severe chemical corrosion, and disordered electrochemical deposition behavior of the zinc metal anode. To address these issues, herein, we propose a facile and effective electrolyte modulating strategy to construct a physico-chemo-electrochemically coupled stable interface between the aqueous electrolyte and zinc anode. The aqueous electrolyte modified using a tiny amount of water-soluble ionic liquid 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF4) can form a positively charged organic EMIM+ adsorption layer and a protective inorganic Zn2+-conducting layer through the in situ decomposition of BF4− on the zinc anode surface, thus effectively homogenizing the Zn2+ diffusion flux and decreasing the chemical corrosion rate. Moreover, EMIM+ provides an electrostatic shielding layer, leading to the preferential and ordered electrodeposition of Zn2+ along the Zn (002). Benefiting from this physico-chemo-electrochemically multifunctional interfacial layer, the Zn//Zn symmetric cells achieve a considerably extended lifespan of up to 1200 h at 5 mA cm−2 and 5 mA h cm−2, and more than 450 h even at an ultrahigh current density and large deposition capacity (10 mA cm−2 and 10 mA h cm−2). Zn//Cu asymmetric cells also exhibit excellent reversibility with a high coulombic efficiency of 99.75%. Furthermore, the physically, chemically, and electrochemically stabilized interface enables the AZMB with a quinone-based cathode to offer high specific capacity (256.9 mA h g−1) and a decent capacity retention rate (83.9% after 300 cycles).
研究领域:
电化学
·
能源材料
·
界面科学
·
储能技术
·
材料化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）