Heliyon
·
2022
·
IF 3.776
Xiang Liu,Yongliang Wang,Li Xiao,Licheng Ma,Peiwei Han,Shufeng Ye
Gold is a valued, critical element whose chemical activation or extraction is challenging. Non-cyanide extraction of gold is now the focus, and N-bromosuccinimide(NBS) is attracting attention. Herein, new insights into the possible mechanism are deeply revealed through comprehensive analysis and detection of the reaction by using elementary gold and gold bearing ore. Experiments on gold foil indicate that Au can be activated in NBS solution to perform a satisfactory dissolution. Application of NBS in gold extraction from ore show a high yield of 86.24% under optimal conditions of NBS dosage 0.05 M, liquid-solid ratio 4:1, stirring speed 400 rpm, pH 8, 25 °C and leaching for 20 h, while yields of other coexisting metals are nearly negligible. The process leads to direct, efficient, one-pot conversion of gold, into simple water-soluble salts. Characterizations show that the framework of NBS are not destroyed, only bromine separates from the framework. The oxidation of neutral gold atom to trivalent Au (III) occurs in a mild, clean and room-temperature chemistry, which converts gold to [AuBr 4 ] - , and the framework to succinimide. The active bromine and radical Br (Br•) generated from in-situ autocatalysis of NBS are responsible for this. The systematic results herald a green procedure for preparation of gold derivatives and gold extraction industry.
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DOI
PubMed
高影响因子
Catalysts
·
2023
·Vol. 14
·期 1
·23
·
IF 3.9
Zi-Han Zhang,An-Qi Wang,Bao-Di Ma,Yi Xu
The effective synthesis ofN-benzyl cyclo-tertiary amines using imine reductase, key components in natural products and pharmaceutical synthesis, is a green approach. Traditional methods faced challenges with enzyme activity and selectivity. This study focused on enhancingMesorhizobiumimine reductase (MesIRED) for betterN-benzyl cyclo-tertiary amine production. Through alanine scanning and consensus mutation, 12 single-siteMesIRED mutants were identified from 23 candidates, showing improved conversion ofN-benzylpyrrolidine andN-benzylpiperidine. Notably, mutants from I177, V212, I213, and A241 significantly boosted conversions. The best-performing mutant forN-benzylpyrrolidine,MesIREDV212A/I213V(M1), increased conversion from 23.7% to 74.3%. ForN-benzylpiperidine,MesIREDV212A/I177A/A241I(M2) enhanced conversion from 22.8% to 66.8%. Tunnel analysis revealed M1 and M2 have more efficient tunnels for larger product movement compared to wild-typeMesIRED. Using recombinantE. colicoexpressingMesIRED and glucose dehydrogenase (GDH), high conversions were achieved: 75.1% forN-benzylpyrrolidine (M1) and 88.8% forN-benzylpiperidine (M2). A preparative experiment resulted in 86.2% conversion and 60.2% yield forN-benzylpiperidine. This research offers an efficient method for engineering IRED, significantly improving conversion and selectivity forN-benzyl cyclo-tertiary amines, aiding drug synthesis and providing insights into rational design of other enzymes.Keywords:imine reductase;N-benzyl cyclo-tertiary amines;alanine scanning;consensus mutation;whole-cell biocatalysis;coexpression
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高影响因子
DIAMOND AND RELATED MATERIALS
·
2023
·
IF 4.1
Feng Wei,Yuchen Guo,Shichao Wang,Yaojie Gao,Jun Qiao,Songlin Ran,Mengcheng Han
Supercapacitors (SCs) have been widely used owing to their merits of long cycle life, excellent physiochemical stability and zero-carbon emission. However, the low energy density of SCs restricts their further applications. Herein, the N, P doped carbon nanosheets (NPCNs) were prepared by using silicon-removed carbon as carbon resource derived from rice husk . The as-prepared NPCN not only possesses a large surface area of 1701.6 m 2 g −1 and a high ratio of mesopore volume to total pore volume (62.11 %) for adsorption and transfer of electrolyte ions , but also has a suitable nitrogen and phosphorus content for electron conduction and contribution of additional active sites to generate pseudo-capacitance through redox. Therefore, the excellent electrochemical properties have been obtained for NPCN-based SCs in the alkaline electrolyte , e.g. satisfactory capacitance of 396.1 F g −1 at 0.1 A g −1 , outstanding rate properties of 319.2 F g −1 at 40 A g −1 , long cyclability with capacitance decay of 0.95 % after 30,000 cycles. Additionally, the energy density of the NPCN-based SCs with neutral electrolyte and ionic liquid electrolyte increased 2.67-fold and 11-fold to 33.25 and 137.24 Wh kg −1 , respectively. This study opens up a feasible route by crafting heteroatoms and using high voltage window electrolyte to obtain the high energy density for SCs.
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高影响因子
Nano Research
·
2021
·Vol. 15
·期 3
·1824-1830
·
IF 8.897
Wang Chao,Li Wen,Wang Xiaodan,Yu Nan,Sun Hongxia,Geng Baoyou
Molybdenum phosphide is a potential hydrogen evolution reaction (HER) catalyst. However, traditional high-temperature phosphating preparation methods are prone to damage of material morphology and agglomeration. Using the carbon skeleton to limit the size and morphology of MoP and to improve the conductivity of the material is an effective method to improve the performance of the catalyst. However, there is a lack of research on the effect of carbon skeleton and MoP composite structure on the catalytic mechanism of HER. We coated ZIF-8 on the surface of MoP nanorods, and obtained open N-doped carbon-coated porous MoP nanorods (N/C/MoP) through carbonization and phosphating. Studies have shown that the ZIF-8 coating effectively limits the size and morphology of the material and avoids agglomeration. Under alkaline conditions, N/C/MoP has a low overpotential of 169 mV for HER at 10 mA/cm 2 , which is 55 mV lower than MoP without a carbon layer. At the same time, its Tafel slope (51.3 mV/dec) is smaller than Pt/C (59.9 mV/dec), and it has good stability. Density functional theory (DFT) studies have shown that under alkaline conditions, there is a synergistic effect between the open N-doped carbon layer and the exposed MoP active surface, which reduces the activation energy of water and improves the catalytic performance of HER. It is worth noting that a tight coating will hinder the exposure of active sites and reduce catalytic activity.
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高影响因子
Nanoscale
·
2019
·Vol. 11
·期 41
·19506-19511
·
IF 6.97
Ying Li,Tong Liu,Wenxiu Yang,Zhijun Zhu,Yanling Zhai,Wenling Gu,Chengzhou Zhu
Non-Pt catalysts with excellent performance regarding the oxygen reduction reaction (ORR) have aroused enormous interest in recent years. Herein, we propose a dual-template method to synthesize a multiscale porous Fe–N–C (FeNC) catalyst. SiO2 and Zn are used as co-templates to produce a multiscale porous structure. Chitosan and glutaraldehyde are used as building blocks to fabricate the frameworks of the hydrogel. After lyophilization and annealing treatments, FeNC aerogel with a multiscale porous structure could be obtained. The as-prepared FeNC catalyst annealed at 900 °C (FeNC-900) exhibits a larger electrochemically active surface area and an improved ORR activity compared to FeNC annealed at other temperatures. FeNC-900 shows a superior ORR performance in comparison with that of commercial Pt/C in terms of the onset potential and half-wave potential, i.e., 0.959 and 0.837 V, which are 28 mV and 10 mV higher than those of Pt/C, respectively. Multiscale porosity is responsible for the outstanding ORR performance of FeNC-900. The electron transfer number of FeNC-900 for the ORR was calculated to be 3.95, which is comparable with that of Pt/C. In addition, the FeNC-900 catalyst possesses an excellent long-term duration and anti-poisoning capacity against methanol crossover. All these results endow the FeNC catalyst with tremendous potential for use in fuel cells.
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高影响因子
SOLAR ENERGY
·
2016
·
IF 3.685
Haifeng Yang,Jincheng Zhang,Chunfu Zhang,Jingjing Chang,Zhenhua Lin,Dazheng Chen,Xu Sun,He Xi,Genquan Han,Yue Hao
In this work, we demonstrated a high performance planar heterojunction perovskite solar cell with the polyethylenimine ethoxylated (PEIE) interlayer. By adopting a less polar solvent for PEIE, enhanced device performance and uniformity are achieved. The power conversion efficiency (PCE) of the best device increases by 22% compared to the reference device and reaches 14.82% with J SC of 19.45 mA/cm 2 , V OC of 1.00 V, and FF of 76.31% under AM 1.5G 100 mW/cm 2 light illumination. The UPS measurement shows that the PEIE layer can effectively decrease the energy offset between PCBM and metal electrode. The recombination mechanism was explored by measuring V OC and J SC at various light intensities from 100 to 0.1 mW/cm 2 . It shows that the PEIE layer can suppress the trap-assisted recombination for the devices. The enhancement of the probability of the carriers collection also shows that the recombination is reduced by the PEIE interlayer. Moreover, it is found PEIE layer can improve the stability of the device.
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高影响因子
RSC Advances
·
2021
·Vol. 11
·期 56
·35663-35672
·
IF 3.361
Fang Wang,Zhenzhou Zhu,Jia Guo
ZnO and g-C3N4 provide excellent photocatalytic properties for degradation of antibiotics in pharmaceutical wastewater. In this work, 2D–2D ZnO/N doped g-C3N4 (NCN) composite photocatalysts were prepared for degradation of tetracycline (TC), ciprofloxacin (CIP) and ofloxacin (OFLX). The addition of ZnO resulted in higher separation efficiency and lower recombination rate of photogenerated charge under visible light. The composite photocatalyst showed better degradation performance compared to ZnO or NCN alone. The TC degradation reached 81.3% in 15 minutes by applying the prepared 20% ZnO/NCN composite photocatalyst, showing great competitiveness among literature reported g-C3N4 based photocatalysts. After 30 minutes, the degradation rate of TC, CIP and OFLX reached 82.4%, 64.4% and 78.2%, respectively. The TC degradation constant of the composite photocatalyst was 2.7 times and 6.4 times higher than NCN and CN, respectively. Radical trapping experiments indicated that ·O2− was the dominant active substance. The transference of excited electrons from the conduction band (CB) of NCN to ZnO enhanced the separation of photogenerated electron–hole pairs and simultaneously suppressed their recombination. This study provides a possibility for the design of high-performance photocatalysts for antibiotics degradation in wastewater.
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高影响因子
Advanced Materials Interfaces
·
2019
·Vol. 6
·期 9
·1802088
·
IF 4.713
Nianxiang Shi,Baojuan Xi,Zhenyu Feng,Jincheng Liu,Denghu Wei,Jing Liu,Jinkui Feng,Shenglin Xiong
Lithium–sulfur batteries are deemed to be one of the most promising energy storage alternatives due to the high theoretical capacity and cost-effectiveness. The significant challenge in exploring novel sulfur host materials is to simultaneously inhibit the shuttle effect and heighten the reaction kinetics. Herein, a novel hybrid host consisting of W 2 C atomic nanoclusters (NCs) grown on a N/P-codoped graphene framework (W 2 C@N/P-rGO) is designed and fabricated for the first use in lithium–sulfur batteries. By means of first-principle calculations and the kinetics analysis including lithium ion diffusion coefficient and charge transfer resistance, the introduction of W 2 C atomic NCs benefits the enhancement of electrochemical kinetics on a polar hybrid conductor. Furthermore, the intense ability of chemically sequestrating the soluble polysulfides by W 2 C atomic NCs ensures the high utilization of sulfur, making the high capacity retention. With a high sulfur loading of 3.1 mg cm −2 , the W 2 C@N/P-rGO/sulfur composite cathode indicates a significantly enhanced electrochemical performance. This work may open up a new avenue to design novel host candidates for advanced lithium–sulfur batteries.
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高影响因子
APPLIED SURFACE SCIENCE
·
2015
·
IF 2.711
Zailin Gong,Shujin Li,Weifang Han,Jiaping Wang,Jun Ma,Xiangdong Zhang
The graphene oxide (GO) was synthesized with Brodie's method and grafted with poly ( N -isopropylacrylamide) (NIPAM) in aqueous solution at ambient temperature. Compared with the initial GO, the PNIPAM graft GO (GO-PNIPAM) has larger surface area, pore volume and self-flocculation effect with rapid response to temperature. Moreover, the GO-PNIPAM also has selective adsorptions with different phenol pollutants because of the different interactions of hydrogen bonds and the molecule structure of the adsorbates. Compared with phenol and bisphenol A, hydroquinone has better adsorption on GO-PNIPAM because of the ample phenolic hydroxyl group and the appropriate molecule structure. The adsorption performance of hydroquinone on GO-PNIPAM is also temperature sensitive because of the thermoresponsive transition of the hydrogen bond. The thermoresponsive adsorption and self-flocculation will make the GO-PNIPAM recyclable in the potential water remediation.
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高影响因子
ENVIRONMENTAL RESEARCH
·
2025
·
IF 7.7
Juncheng Zheng,Han Song,Yuankun Yang,Haidong Li,Xuemei Luo,Shu Chen
Persulfate (PDS)-based advanced oxidation processes have emerged as promising methods for antibiotic removal, but achieving high catalytic efficiency for tetracycline (TC) degradation remains difficult. The catalytic performance of FeGCB-N in PDS activation depended on Fe content and pyrolysis temperature, with defect density and intermetallic compound formation largely determined by the pyrolysis temperature. The optimized Fe 0.2 GCB-N-800 exhibited remarkable PDS activation performance for tetracycline degradation, achieving over 99% removal within 65 min under conditions of 10 mg·L -1 TC, 1 mM PDS, and pH 3. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) collectively indicate that surface oxygen-containing functional groups, defect sites, and intermetallic Fe compounds provide active sites for PDS activation by FeGCB. Electron paramagnetic resonance (EPR) and quenching results demonstrated that superoxide radicals (O 2 •- ) and sulfate radicals (SO 4 •− ) were the primary reactive species in TC degradation. Density functional theory (DFT) calculations indicate that Fe-N is the key active site for PDS activation. Based on DFT results and liquid chromatography-mass spectrometry (LC-MS) analysis, potential degradation pathways for tetracycline (TC) are proposed. ECOSAR toxicity assessment showed that the O 2 •- -mediated pathway would generate fewer toxic byproducts. This work offers an effective approach to design environment friendly catalysts from algae biomass for treating wastewater.
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2025
·
IF 5.2
Jiaqi Luo,Yingchen Wang,Qiutong Zhang,Wenhao Yan,Yimin Jia,Mingting Yuan,Qiushuo Yu,Xinyue Zhai,Yuan Zou
N -phenylanthranilic acid (NPAA) is weakly acidic compound that exhibits both excited-state intramolecular proton transfer (ESIPT) and aggregation-induced emission (AIE) characteristics. The molecular structure was confirmed, and its optical behavior was rationalized through a combined approach of quantum chemical calculations and experimental studies. At low concentrations in various solvents, NPAA exhibits dual emission, indicative of an ESIPT process. At higher concentrations, self-association leads to the formation of dimers, resulting in a single emission peak in the fluorescence spectrum. The emission intensity significantly increases with an increasing water fraction in methanol/H 2 O mixtures, demonstrating typical AIE behavior. Additionally, NPAA exhibits time-dependent enhancement of blue-shifted emission and pH-dependent fluorescence responses. Upon adding a large amount of water to the methanol solution (up to about 70 % water fraction), the mixture shows a gradual enhancement accompanied by a blue shift in fluorescence emission. Under alkaline conditions, the carboxyl group becomes negatively charged, which increases intermolecular electrostatic repulsion and weakens hydrogen bonding interactions. As a result, molecular aggregation is inhibited, leading to fluorescence quenching. In contrast, under acidic conditions, the molecules aggregate more readily, which enhances fluorescence emission, and the crystal morphology changes from needle-like to sheet-like. NPAA thus exhibits reversible acid-base responsive fluorescence switching behavior. Furthermore, NPAA films enable reversible fluorescence switching under acid/base vapor stimuli, demonstrating its potential in vapor-responsive luminescent sensing.
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DOI
高影响因子
LUMINESCENCE
·
2025
·Vol. 40
·期 11
·e70357
·
IF 3
Li Li,Yulu Xia,Ming Zhang
Carbon nanoparticles (CNPs) integrated with nanomaterial-based quenchers have emerged as an innovative platform for developing advanced sensing systems. In this study, we developed a novel fluorescent sensing platform for the highly sensitive detection of hydroxylamine (HA). Through a one-step hydrothermal synthesis approach, nitrogen and sulfur co-doped carbon nanoparticles (N,S-CNPs) were successfully prepared using dimethylamine hydrochloride and dimethyl sulfoxide (DMSO) as precursors. The synthesized N,S-CNPs demonstrated exceptional fluorescence properties, achieving a remarkably high quantum yield of 50%, along with outstanding water solubility, photostability, and chemical stability. The fluorescence emission of N,S-CNPs could be effectively quenched by manganese dioxide (MnO 2 ) nanosheets through a combined mechanism of inner filter effect (IFE) and static quenching effect (SQE). Notably, HA induced the redox-mediated decomposition of MnO 2 nanosheets, converting MnO 2 to Mn 2+ ions and consequently restoring the fluorescence of N,S-CNPs (turn-on response). Under optimized conditions, the proposed sensor exhibited a wide linear detection range (0.1–200 μM) with an ultra-low detection limit of 0.04 μM. The sensor demonstrated excellent analytical performance in real-world applications, successfully detecting HA in lake and river water samples with high accuracy and reliability. These findings highlight the great potential of this fluorescent sensing platform for environmental monitoring and water quality assessment.
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DOI
PubMed
高影响因子
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