CERAMICS INTERNATIONAL
·
2019
·
IF 3.45
Honghong Lei,Peng Jiang,Bin Li,Yuncheng Zhou,Rui Zhang,Jianlei Kuang,Wenbin Cao,Wei Wang
The (S, N) co-doped Ba 2 In 2- x Cr x O 5+ y (0 ≤ x ≤ 0.5) oxides are successfully obtained by mixing the Ba 2 In 2- x Cr x O 5+ y oxides and thiourea through a simple ball milling method followed by sintering at 400 °C for 3 h. The colors of the compounds change from orange-brown to yellow-green after reacting with thiourea. When Cr amount is small ( x = 0.1), the crystal structure of (S, N) co-doped Ba 2 In 2- x Cr x O 5+ y is orthorhombic Ba 2 In 2 O 5 phase. When x ≥ 0.3, the crystal structure of the sample is cubic BaInO 2.5 phase. And this phase transition is the same as Ba 2 In 2- x Cr x O 5+ y . XPS results reveal that Cr 6+ in Ba 2 In 2- x Cr x O 5+ y (0 ≤ x ≤ 0.5) oxides are reduced to Cr 3+ after sintering. S exists in both cation and anion forms, and N exists in substitutional forms. UV–Vis analysis indicates that the yellow-green hue comes from the d-d transition of Cr 3+ , and the doping of S, N ions leads to a red shift of the absorption edge of the samples.
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 16
·8753-8758
·
IF 3.049
Zhilong Xu,Lei Fan,Xiangying Ni,Jie Han,Rong Guo
Tin (Sn) has wide prospects in applications as an anode electrode material for Li-ion batteries, due to its high theoretical specific capacity. However, the large volume expansion of Sn during the charge–discharge process causes a performance reduction of lithium-ion batteries (LIBs). Here, Sn encapsulated N-doped porous carbon fibers (Sn/NPCFs) were synthesized through an electrospinning method with a pyrolysis process. This structure was beneficial for the lithium ion/electron diffusion and buffered the large volume change. By adjusting the amount of Sn, the hybrid carbon fibers with different Sn/carbon ratios could be prepared, and the morphology, composition and properties of the Sn/NPCFs were characterized systematically. The results indicated that the Sn/NPCFs with a Sn-precursor/polymer weight ratio at 0.5 : 1 showed the best cycling stability and specific capacity, preserving the specific capacity of 400 mA h g−1 at the current density of 500 mA g−1 even after 100 cycles.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Quanfa Zhong,Qintie Lin,Runlin Huang,Hengyi Fu,Xiaofeng Zhang,Haoyu Luo,Rongbo Xiao
A nitrogen and copper codoped biochar (N-Cu/biochar) material was prepared and used to activate persulfate (PS) for tetracycline (TC) degradation. The material was characterized by SEM, FT-IR, XRD and XPS. The results showed that the N-Cu/biochar had a flaky carbon structure with urchin-like copper growing on the carbon surface, a large specific surface area of 352.43 m 2 /g that provided sufficient active sites for catalytic reaction, and abundant functional groups. Quenching experiments and electron paramagnetic resonance (EPR) experiments verified the reaction pathway mechanisms. The main free radical in the system was HO ; another possible mechanism is the nonradical pathway of electron transfer between TC and PS on the surface of the catalyst, and this electron transfer could lead to TC degradation. All the TC was removed within 120 min at a catalyst dosage of 200 mg/L, PS dosage of 0.5 mM, and pH of 7.0. Chloride and bicarbonate ions had little effect on the degradation of TC. HPLC-MS was used to investigate the main degradation intermediates and the possible transformation pathways were proposed. The toxicity of TC and its intermediates were evaluated by bioluminescence inhibition method. The high catalytic efficiency and low consumables of the N-Cu/biochar/PS system could provide a new strategy for the remediation of wastewater.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Xingzheng Liu,Junsheng Jin,Yueliang Chen,Boting Lu,Qian Sun,Jiexin Wang,Jian-feng Chen,Yuan Le
Poly ( n -butyl cyanoacrylate) (PBCA) nanoparticles are widely used as biocompatible and bio-erosive materials in a range of biomedical applications, especially for drug delivery systems. This paper reports a novel synthesis method of PBCA nanoparticles with high productivities and purities in a rotating packed bed. The particle size and molecular weight of PBCA nanoparticles were controlled by adjusting the high-gravity factor, surfactant concentration, pH, temperature and monomer concentration. The high-gravity factor shows an obvious influence on the particle sizes, while it has few effects on molecular weight. The surfactant concentration and pH also affect molecular weight and particle sizes. Moreover, compared with conventional stirred tank, the reaction time of RPB procedure was dramatically reduced from 12 h to 2 h, and the purity of products increased from about 93% to 96%. Furthermore, when the molecular weight of PBCA increased, the in vitro cytotoxicity to Hep G2 cells firstly increased and then decreased, and the cellular uptake was improved. In summary, PBCA with controllable molecular weight and particle sizes can be synthesized using a facile high-gravity method.
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2019
·
IF 12.221
Xingxing Li,Yu Pan,Hong Yi,Jingcheng Hu,Dali Yang,Fengzhi Lv,Wendian Li,Jinping Zhou,Xiaojun Wu,Aiwen Lei,Lina Zhang
Improving the selectivity and retaining the efficiency of catalysts are essential for industrial processes and remain a great challenge. Herein, we developed a facile route to synthesize Pd nanocubes (NCs) using Eosin Y as the photosensitizer under visible light. Subsequently, Pd NCs were uniformly loaded on N-doped carbon nanofibrous microspheres (NCMs) from carbonated chitin microspheres. This Pd NCs@NCM exhibited high reactivity and selectivity in alkyne semihydrogenation. For example, the hydrogenations of phenylacetylene to styrene and of 3-phenyl-2-propyn-1-ol to (Z)-cinnamyl alcohol were 12.9 and 18.3 times faster with Pd NCs@NCM than with Lindlar catalyst. According to the Mott–Schottky effect, loading of Pd NCs on N-doped carbon constructed a rectifying contact and decreased the electron density of Pd NCs. Density functional theory (DFT) calculations suggested that the high concentration of holes doped in Pd NCs weakened the interaction of alkenes on the Pd (100) facet and prevented further hydrogenation for a long time; this period of durable time is very helpful in chemical manufacturing. Thus, Pd NCs@NCM maintained both high reactivity and selectivity in comparison with surface-modified catalysts. This work provides an alternative strategy to design Mott–Schottky catalysts for selective hydrogenation reactions.
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2018
·Vol. 8
·期 11
·900
·
IF 3.504
Longshi Rao,Yong Tang,Hanguang Lu,Shudong Yu,Xinrui Ding,Ke Xu,Zongtao Li,Jin Z. Zhang
We developed a microreactor with porous copper fibers for synthesizing nitrogen-doped carbon dots (N-CDs) with a high stability and photoluminescence (PL) quantum yield (QY). By optimizing synthesis conditions, including the reaction temperature, flow rate, ethylenediamine dosage, and porosity of copper fibers, the N-CDs with a high PL QY of 73% were achieved. The PL QY of N-CDs was two times higher with copper fibers than without. The interrelations between the copper fibers with different porosities and the N-CDs were investigated using X-ray photoelectron spectroscopy (XPS) and Fourier Transform infrared spectroscopy (FTIR). The results demonstrate that the elemental contents and surface functional groups of N-CDs are significantly influenced by the porosity of copper fibers. The N-CDs can be used to effectively and selectively detect Hg2+ions with a good linear response in the 0~50 μM Hg2+ions concentration range, and the lowest limit of detection (LOD) is 2.54 nM, suggesting that the N-CDs have great potential for applications in the fields of environmental and hazard detection. Further studies reveal that the differentdorbital energy levels of Hg2+compared to those of other metal ions can affect the efficiency of electron transfer and thereby result in their different response in fluorescence quenching towards N-CDs.Keywords:microreactor;carbon dots;porous copper fibers;Hg2+detection
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POWER SOURCES
·
2019
·
IF 7.467
Yun Gu,Le-Qing Fan,Jian-Ling Huang,Cheng-Long Geng,Jian-Ming Lin,Miao-Liang Huang,Yun-Fang Huang,Ji-Huai Wu
This work reports the preparation of N-doped reduced graphene oxide decorated NiSe 2 nanoparticles (N-rGO/NiSe 2 ) in the presence of different amount of graphene oxide reactant by a simple two-step process, which contains hydrothermal preparation of Ni(OH) 2 precursor and then solvothermal synthesis of N-rGO/NiSe 2 composites with different content of N-rGO. The as-prepared N-rGO/NiSe 2 composites is characterized by power X-ray diffraction, Raman spectroscopy , high-resolution X-ray photoelectron spectroscopy, field emission scanning electron microscopy , transmission electron microscopy, energy-dispersive X-ray spectroscopy and N 2 adsorption–desorption isotherm. The results show that N-rGO acts as supporter of NiSe 2 nanoparticles to prevent them from aggregation, leading to the increase in specific surface area and electrical conductivity of material. The optimized N-rGO/NiSe 2 composite can deliver high specific capacitance of 2451.4 F g −1 at a current density of 1 A g −1 . Using activated carbon (AC) as negative electrode and the optimized N-rGO/NiSe 2 composite as positive electrode , an asymmetric supercapacitor is constructed. This fabricated asymmetric supercapacitor can work stably under the potential window of 0–1.6 V, and presents the maximum energy density of 40.5 Wh kg −1 at a power density of 841.5 W kg −1 . Moreover, the N-rGO/NiSe 2 //AC asymmetric supercapacitor exhibits good cyclic stability.
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Zhenyu Wang,Yu Huang,Meijuan Chen,Xianjin Shi,Yufei Zhang,Junji Cao,Wingkei Ho,Shun Cheng Lee
The development of catalysts that effectively activate target pollutants and promote their complete conversion is an admirable objective in the environmental photocatalysis field. In this work, graphitic carbon nitride (g-C3N4) microtubes with tunable N-vacancy concentrations were controllably fabricated using an in situ soft-chemical method. The morphological evolution of g-C3N4, from the bulk to the porous tubular architecture, is discussed in detail with the aid of time-resolved hydrothermal experiments. We found that the NO removal ratio and apparent reaction rate constant of the g-C3N4 microtubes were 1.8 and 2.6 times higher than those of pristine g-C3N4, respectively. By combining detailed experimental characterization and density functional theory calculations, the effects of N-vacancies in the g-C3N4 microtubes on O2 and NO adsorption activation, electron capture, and electronic structure were systematically investigated. These results demonstrate that surface N-vacancies act as specific sites for the adsorption activation of reactants and photoinduced electron capture, while enhancing the light-absorbing capability of g-C3N4. Moreover, the porous wall structures of the as-prepared g-C3N4 microtubes facilitate the diffusion of reactants, and their tubular architectures favor the oriented transfer of charge carriers. The intermediates formed during photocatalytic NO removal processes were identified by in situ diffuse reflectance infrared Fourier transform spectroscopy, and different reaction pathways over pristine and N-deficient g-C3N4 are proposed. This study provides a feasible strategy for air pollution control over g-C3N4 by introducing N-vacancy and porous tubular architecture simultaneously.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2018
·
IF 6.14
Lijin Huang,Man He,Beibei Chen,Bin Hu
N-doped magnetic porous carbon (N-MPC) is an emerging adsorbent for water pollution control. However, high cost and multisteps procedure make the direct fabrication of N-MPCs difficult until now. Herein, highly dispersed N-MPCs were synthesized by a facial one-pot solid-state pyrolysis strategy. Heating the mixture of ZnO, Co(OH)2, and 2-methylimidazole (HmIm), Zn/Co bimetallic ZIFs formed at the initial stages, being the primary self-template to produce N-MPCs during subsequent high-temperature treatment. By altering the pyrolysis temperature and the molar ratio of ZnO/Co(OH)2 in the precursor, the magnetism, nitrogen content, and surface areas of N-MPCs can be easily controlled. Due to its high special surface areas and the decoration of abundant nitrogen functional groups (pyrrole-N and pyridinic-N), the optimized N-MPC-700-7/3 exhibited a superior adsorption performance for Hg2+ uptake (489 mg g–1). Moreover, the N-MPCs exhibited fast dynamics in adsorption (K2 = 0.47 g mg–1 min–1) and good chemical stability. The simple, sustainable, and impressive method provides an attractive way to manufacture efficiency MPC sorbents, and the prepared N-MPCs merit good application potential in environmental remediation.
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 46
·26116-26123
·
IF 2.936
Ran Wang,Yufei Liu,Chang Wang,Henghui Li,Xin Liu,Liming Cheng,Yanhong Zhou
Monitoring serum glycomics is one of the most important emerging approaches for diagnosis of various cancers, and the majority of previous studies were based on MALDI-MS or HPLC analysis. Considering the difference of these analytical methods employed for serum glycomics, it is necessary to compare the effectiveness of different analytical methods for monitoring the aberrant changes in serum glycomics. In this study, a strategy based on machine learning was firstly applied for comparing the analysis results of MALDI-MS and HPLC on the same serum glycomics of hepatocellular carcinoma (HCC) samples. The capability of these two analytical methods for identifying HCC is demonstrated by the classification results obtained from MALDI-MS and HPLC data. In addition, by comparing glycomics which were significantly correlated with HCC based on MALDI-MS and HPLC, some N-glycans which may be the potential biomarkers for HCC were identified, validating the capability of these two analytical methods for the differentiated identification in the analysis of glycomics. Meanwhile, it is noteworthy that various physiological and environmental factors may cause the aberrant changes in glycosylation, and all these interference factors may be minimized by analyzing the same sample sets of HCC. Overall, these results showed that MALDI-MS and HPLC are complementary in qualitative and quantitative analysis of serum glycomics.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
·
2018
·
IF 5.116
Xiao Zhang,Jiangwei Li,Yanfang Sun,Zijian Li,Pei Liu,Qingyun Liu,Lin Tang,Jinxue Guo
Searching active and cost-effective bifunctional electrocatalysts for overall water splitting is a vital but challenging task towards clean and sustainable energy sources. Here, mixed metal phosphides of Ni 2 P CoP anchored on N-doped reduced graphene oxide (NiCoP/N-rGO) as efficient and earth-abundant electrocatalysts for water splitting are reported. The large active sites, synergism, and hybridization with N-doped rGO endow NiCoP/N-rGO electrocatalyst with outstanding oxygen evolution reaction activity that is better than benchmark RuO 2 in alkaline electrolyte , as well as active hydrogen evolution reaction in acidic, neutral, and alkaline solution. NiCoP/N-rGO has further been employed as both anode and cathode in a two-electrode alkaline water electrolyzer towards overall water splitting, exhibiting advanced electrochemical performances with a low cell voltage of 1.57 V at a current density of 20 mA cm −2 . Moreover, the overall water splitting in this two-electrode electrolyzer can be driven by a single-cell AA battery (nominal voltage of 1.5 V), making NiCoP/N-rGO as the promising efficient cost-effective catalysts for water electrolysis.
✓ 已验证
产品关联
DOI
高影响因子
Nano Research
·
2018
·Vol. 11
·期 4
·1905-1916
·
IF 7.994
Jia Nan,Weng Qiang,Shi Yaru,Shi Xinyan,Chen Xinbing,Chen Pei,An Zhongwei,Chen Yu
Highly efficient metal-free, carbon-based, bi-functional electrocatalysts for the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) have attracted increased attention for use in electrochemical energy conversion systems, owing to their low cost and high activity. In this work, N-doped carbon nanocages (N-CCs) with a porous self-supported architecture and high specific surface area are synthesized by a facile interfacial assembly synthetic route. The materials are comprehensively characterized by scanning electron microscopy, transmission electron microscopy, nitrogen adsorption–desorption experiments, X-ray diffraction, and X-ray photoelectron spectroscopy. Cyclic voltammetry, chronoamperometry, and linear sweep voltammetry demonstrate that the as-prepared N-CC could serve as an effective metal-free electrocatalyst with excellent catalytic activity, long-term operation durability, and excellent methanol tolerance for the ORR in alkaline media. In the presence of 3 mM methanol, the half wave potential of the N-CCs for the ORR is 190 mV; this is more positive than that of the commercial Pt/C electrocatalyst. Meanwhile, the N-CCs also show an OER activity comparable to that of the commercial Ru/C electrocatalyst, revealing their bifunctional property.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）