Small Methods
·
2022
·Vol. 6
·期 12
·2201142
·
IF 15.367
Ce Qiu,Jia Liu,Hanghui Liu,Xiaohui Zhu,Liang Xue,Shuang Li,Mingzhu Ni,Yang Zhao,Tong Wang,Serguei V. Savilov,Sergey M. Aldoshin,Hui Xia
Although birnessite-type manganese dioxide (δ-MnO 2 ) with a large interlayer spacing (≈7 Å) is a promising cathode candidate for aqueous Zn/MnO 2 batteries, the poor structural stability associated with Zn 2+ intercalation/deintercalation limits its further practical application. Herein, δ-MnO 2 ultrathin nanosheets are coupled with reduced graphene oxide (rGO) via van der Waals (vdW) self-assembly in a vacuum freeze-drying process. It is interesting to find that the presence of vdW interaction between δ-MnO 2 and rGO can effectively suppress the layered-to-spinel phase transition in δ-MnO 2 during cycling. As a result, the coupled δ-MnO 2 /rGO hybrid cathode with a sandwich-like heterostructure exhibits remarkable cycle performance with 80.1% capacity retained after 3000 cycles at 2.0 A g −1 . The first principle calculations demonstrate that the strong interfacial interaction between δ-MnO 2 and rGO results in improved electron transfer and strengthened layered structure for δ-MnO 2 . This work establishes a viable strategy to mitigate the adverse layered-to-spinel phase transition in layered manganese oxide in aqueous energy storage systems.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
·
2022
·
IF 3.752
Qian WEI,Liu-yang DONG,Cong-ren YANG,Xue-duan LIU,Fen JIAO,Wen-qing QIN
Lime (CaO) and sodium humate (NaHA) were used as the combined depressant for arsenopyrite pre-treated by CuSO 4 and butyl xanthate. Micro-flotation tests show that the combined depressant CaO and NaHA achieved the selective depression of arsenopyrite. Closed-circuit lab-scale test results indicate that the synergistic effect of CaO+NaHA achieved a satisfactory flotation separation of sphalerite and arsenopyrite, for which the Zn grade and recovery of Zn concentrate were 51.21% and 92.21%, respectively. Contact angle measurements, adsorption amount measurements and X-ray photoelectron spectroscopy analysis indicate that the dissolved calcium species (mainly as Ca 2+ ) were adsorbed on the mineral surfaces, thereby promoting NaHA adsorption. Moreover, the surface of the arsenopyrite absorbed more amount of calcium species and NaHA than that of the sphalerite, thereby accounting for the strong hydrophilic surface of arsenopyrite. The adsorption of NaHA on arsenopyrite was mainly chemical adsorption through its carboxyl groups and Ca atoms, whereas that on sphalerite surface was relatively weak.
✓ 已验证
产品关联
DOI
高影响因子
LANGMUIR
·
2022
·
IF 4.331
Xiaoting Cao,Ruili Song,Xiaoshuang Zhou,Xi Wang,Xu Dong,Ningyi Yuan,Jianning Ding
Electrocatalysts with high cost-effectiveness for the oxygen reduction reaction (ORR) are essential for fuel cells (FC) and Zn-Air batteries (ZAB), which need highly active sites and suitable carbon substrates to accelerate the charge transfer kinetics. Herein, a simple and extensible method using ball milling and space-confinement pyrolysis is reported to prepare a series of transition metals and N-C catalysts (M-NLPC), which possess three-dimensional porous carbon substrates and dense active sites for efficient ORR. M-NLPC catalysts (especially Fe-NLPC) exhibit outstanding ORR activity with a half-wave potential (E1/2, 0.88 V) in an alkaline medium, high stability, and strong methanol resistance. The M-N4 sites are proven to be the active centers in M-NLPC by theoretical calculation, and methanol molecules are more likely to desorb than react on the Fe-N4 sites, which is the origin of the inactivity for the methanol oxidation reaction (MOR). Furthermore, Fe-NLPC was applied to membraneless alkaline direct methanol FC (DMFC) in practice, exhibiting outstanding performance. Meanwhile, the Fe-NLPC-based ZAB also shows excellent electrochemical performance.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Zhenzhen Wang,Xiaozhuang Zhou,Huihui Jin,Ding Chen,Jiawei Zhu,Rolf Hempelmann,Lei Chen,Shichun Mu
Developing bifunctional ORR&OER electrocatalysts with high activity and stability is challenging for practical application of rechargeable Zinc air batteries. Herein, an ionic liquid strategy is proposed for construction of FeCo alloys encapsulated in nitrogen-doped carbon as bifunctional electrocatalyst for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). By taking advantages of the unique properties such as solvent effect and low volatility, ionic liquid serves as solvent to disperse metal ions in the precursor preparation and nitrogen-containing carbon source during pyrolysis. The FeCo alloy nanoparticles encapsulated in the N-doped carbon matrix show a homogeneous distribution with average sizes of 50–100 nm. Such a core-shell structure endows the catalyst with both high ORR and OER activity and robust stability in alkaline environments. Especially, the half-wave potential (E 1/2 ) for ORR is 0.86 V and the overpotential (E over ) for OER to reach the 10 mA·cm −2 current density is only 280 mV. Furthermore, the obtained bifunctional electrocatalyst also displays high efficiency and great durability when applied in the rechargeable Zn-air battery. The specific capacity and energy density at the discharge current density of 10 mA·cm −2 reach up to 741.5 mAh·g −1 and 830.1 Wh kg −1 , respectively. It’s envisioned that this ultra-facile method would be applicable to synthesize highly efficient catalysts for other energy conversion systems.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE
·
2022
·Vol. 102
·期 11
·4714-4723
·
IF 4.125
Ke Cheng,Jianghua Zhang,Shasha Yang,Fawen Yin,Zixuan Li,Ting Wang,Dayong Zhou
BACKGROUND Efficient and sustainable production of structured phospholipids (SPLs) enriched in medium-chain fatty acids (MCFAs) in a heterogeneous manner is crucial for their potential applications in functional foods and drugs. Herein, for the first time, Zn- and Al-incorporated SBA-15 silicas were prepared by the coprecipitation method and further researched for catalytic synthesis of MCFA-enriched SPLs through acidolysis reaction of natural phospholipids with capric or caprylic acid. RESULTS The as-prepared Zn- and Al-incorporated SBA-15 samples exhibited superior catalytic activities under mild experimental conditions (50 °C, 6 h) to commercial homogeneous Lewis acids and benchmark enzymes. Correspondingly, the capric acid and caprylic acid incorporations were respectively achieved up to ~40.25 ± 0.40% (or 35.08 ± 0.09%) and 37.26 ± 0.38% (or 33.02 ± 0.13%) for Zn- (or Al-) incorporated SBA-15 catalyst. Moreover, various methods such as scanning electron microscopy with energy-dispersive X-ray spectrometry, ultraviolet–visible diffuse reflectance spectroscopy and pyridine–Fourier transform infrared spectroscopy were utilized to characterize the two catalysts in order to elucidate the possible structure–performance relationship. Accordingly, the above-mentioned satisfactory results are most probably due to the well-ordered mesostructures and large amounts of active Lewis acid sites existing in the investigated materials. Noticeably, the two catalysts featured good separation and excellent recyclability as well. CONCLUSION The Zn- and Al-incorporated SBA-15 catalysts studied in this work might shed light on novel, sustainable and economic alternatives for effective SPL production to diminish the applications of conventional homogeneous catalysts and biocatalysts in food industries. © 2022 Society of Chemical Industry.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Energy Storage Materials
·
2022
·
IF 20.831
Huan Yang,Shuai Gao,Dewei Rao,Xiaohong Yan
Developing cost-effective and high-efficient bifunctional electrocatalyst for both oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is essential for rechargeable Zn-air battery application. However, achieving high-active dual sites for bifunctional oxygen electrocatalysis in a single catalyst, as well as determining the decisive active sites for OER and ORR to explore the synergistically catalytic mechanism remain challenges. Herein, we propose a catalyst consisting of high-purity pyrrole nitrogen anchored cobalt single-atom (CoN 4 ) and adjacent metallic cobalt sites (Co p @CoNC) for explicit research of dominated active sites. The obtained Co p @CoNC exhibits superior electrocatalytic activity with a small overpotential difference of 0.68 V between OER potential at 10 mA cm −2 and ORR half-wave potential, outperforming commercial noble-metal based catalysts. Electrochemical measurements and theoretical simulations verify the pyrrole-type CoN 4 and adjacent metallic cobalt are separately decisive active sites for ORR and OER activities. Simultaneously, metallic cobalt regulates electron distribution of CoN 4 moiety to improve ORR activity. Importantly, the rechargeable liquid and flexible solid-state Zn-air batteries using Co p @CoNC as air electrode catalysts possess high peak power densities of 188.8 and 121.8 mW cm −2 , respectively. Our findings provide a feasible strategy to design high-performance multifunctional catalysts for rechargeable Zn-air batteries application.
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2023
·Vol. 47
·期 32
·15089-15098
·
IF 3.3
Qixuan Qin,Na Liu,Yan Zhang,Weiyi Bu,Zhijie Zhou,Changhua Hu,Xiaohong Chuai
The sensitivity and selectivity of semiconductor metal oxides can be effectively improved by transition metal doping and noble metal loading. In this work, Ag-loaded p-type Zn-doped Fe2O3 (Ag@Zn–Fe2O3) nanoparticles were synthesized by a combination of a one-step hydrothermal route and a co-precipitation method. The prepared Ag@Zn–Fe2O3 nanoparticles show a peanut-like structure with a size of about 50–150 nm. The Zn doping and the Ag loading can synergistically improve the response of the Fe2O3 nanoparticles to acetone. At the optimum operating temperature (150 °C), the response of the Ag@Zn–Fe2O3 sensor to 100 ppm acetone is 50.2, which is significantly higher than 8.9 and 25.8 corresponding to Fe2O3 and Zn–Fe2O3, respectively. In addition, the Ag@Zn–Fe2O3 sensor exhibits excellent selectivity, good moisture resistance, and long-term stability to acetone. Meanwhile, the possible mechanism of the improved acetone sensing properties is also discussed.
✓ 已验证
产品关联
DOI
高影响因子
DIAMOND AND RELATED MATERIALS
·
2023
·
IF 4.1
Minghui Duan,Guo Zeng,Jian He,Weiguo Wang
Carbon nitride (g-C 3 N 4 ) is a potential material that can be used for the treatment of the wastewater contains organic dyes. However, the photocatalytic efficiency of g-C 3 N 4 is limited by the wide band gap and fast recombination of photon-generated carriers. In this work, the co-doped with Mg and Zn of Mg Zn 0.07 -g-C 3 N 4 was designed and prepared to enhance the photocatalytic efficiency. The co-doped Mg and Zn shorted the band gap of g-C 3 N 4 from 2.74 eV to 2.50 eV. Interestingly, according to the DFT calculation, a Zn-bridge is formed between the interlayers of g-C 3 N 4 . The Zn-bridge reduces the electron localization and prolongs the existence time of photon-generated carriers. The as-prepared Mg Zn 0.07 -g-C 3 N 4 was applied for the photodegradation of methylene blue. The degradation ratios and photodynamic parameter of Mg Zn 0.07 -g-C 3 N 4 are higher than that of g-C 3 N 4 and Mg-g-C 3 N 4 (29.51 × 10 −3 min vs 8.00 × 10 −3 min).
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2023
·Vol. 15
·期 11
·2570
·
IF 5
Dan Wang,Lin-Huan Du,Long Li,Yu-Meng Wei,Tao Wang,Jun Cheng,Bin Du,Yi Jia,Bao-Yi Yu
Coordination polymers (CPs) are organo-inorganic porous materials consisting of metal ions or clusters and organic linkers. These compounds have attracted attention for use in the fluorescence detection of pollutants. Here, two Zn-based mixed-ligand-bearing CPs, [Zn2(DIN)2(HBTC2−)2] (CP-1) and [Zn(DIN)(HBTC2−)]·ACN·H2O (CP-2) (DIN = 1,4-di(imidazole-1-yl)naphthalene, H3BTC = 1,3,5-benzenetricarboxylic acid, and ACN = acetonitrile), were synthesized under solvothermal conditions. CP-1 and CP-2 were characterized by single-crystal X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, elemental analysis, and powder X-ray diffraction analysis. Solid-state fluorescence analysis revealed an emission peak at 350 nm upon excitation at 225 and 290 nm. Fluorescence sensing tests showed that CP-1 was highly efficient, sensitive, and selective for detecting Cr2O72−at 225 and 290 nm, whereas I−was only detected well at an excitation of 225 nm. CP-1 detected pesticides differently at excitation wavelengths of 225 and 290 nm; the highest quenching rates were for nitenpyram at 225 nm and imidacloprid at 290 nm. The quenching process may occur via the inner filter effect and fluorescence resonance energy transfer.Keywords:coordination polymers;fluorescence sensing;d10metal;CP;sensing ions;sensing pesticides
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Jing Cao,Hong Zhou,Cunping Huang,Qiang Wu,Weifeng Yao
The development of highly efficient piezocatalysts has attracted widespread attention for energy conversion and pollution abatement. This paper reports for the first time exceptional piezocatalytic properties of a Zn- and N -codoped porous carbon piezocatalyst (Zn-N x -C) derived from the zeolitic imidazolium framework-8 (ZIF-8) for both hydrogen production and degradation of organic dyes. The Zn-N x -C catalyst has a high specific surface area of 810.6 m 2 /g and retains the dodecahedron structure of ZIF-8. Under ultrasonic vibration, the hydrogen production rate of Zn-N x -C has achieved 6.29 mmol/g/h, surpassing most recently reported piezocatalysts. Additionally, the Zn-N x -C catalyst demonstrates a 94% degradation efficiency for organic rhodamine B (RhB) dye during 180 min of ultrasonic vibration. This work sheds new light on the potential of ZIF-based materials in the field of piezocatalysis and provides a promising avenue for future developments in the area.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOMASS & BIOENERGY
·
2021
·
IF 5.061
Jingyue Wang,Yuelong Xu,Meifang Yan,Bin Ren,Xiaoxi Dong,Junfeng Miao,Lihui Zhang,Xinqiang Zhao,Zhenfa Liu
Porous biomass-carbon materials for supercapacitor applications have recently attracted attention. Chitin , which has abundant amides and hydroxyl groups, was used as an ideal precursor for carbon in this work. The chitin was treated with a one-step method to produce a heteroatom-loaded porous carbon material, and its electrochemical properties were significantly improved through the introduction of loaded elements. A mixture of chitin, zinc chloride , and heteroatoms was carbonized to obtain heteroatoms (N and S) and the bimetallic sulfide loaded hierarchical porous carbon. Then, the porous carbon with S, N, Zn, and Fe heteroatoms loading was used to prepare a supercapacitor with a specific capacitance of 277.4 F g −1 at 1 A g −1 . In addition, the supercapacitor had a specific capacitance retention rate of 90% at 5 A g −1 after 10,000 cycles. Therefore, hierarchical porous carbon materials loaded with heteroatoms and bimetallic sulfide were prepared by carbonization activation with chitin as the precursor. The resulting supercapacitor showed that the as-prepared porous biomass materials possessed ideal charging-discharging performance. Moreover, this work provides strategies for obtaining metal sulfides and heteroatom co-loading of carbon materials with excellent properties using a simple and efficient one-step method for renewable energy storage device applications.
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2021
·
IF 5.455
Zhongqing Wang,Lan Zhou,Rui Li,Konggang Qu,Lei Wang,Wenjun Kang,Haibo Li,Shenglin Xiong
The development of non-previous-metal electrocatalyst with low cost, high activity and stability towards oxygen reduction reaction (ORR) remains a challenge. Covalent organic frameworks (COFs) have emerged as promising candidates for the preparation of porous metal/nitrogen co-doped carbon catalysts. In the present work, porous Fe-N x nanoclusters/carbon catalysts are prepared by pyrolyzing iron-containing covalent-triazine organic frameworks. It is found that the synthesis conditions including pyrolysis temperature and pressure have great impacts on the surface area of micropores, mesopores and macropores, which in turn influences the ORR activity of catalysts by varying the mass diffusion and the contact of active centers with electrolytes. The optimized catalyst (denoted as Fe 1.2 NC-0.02-800), having the highest both BET and external surface areas, shows much higher kinetic current density and catalytic stability than commercial Pt/C catalyst in ORR process. When being assembled into Zn-air battery, it also exhibits excellent performances in terms of open circuit voltage (1.45 V), power density (210 mW cm −2 at 330 mA cm −2 ) and specific capacity (713.1 mA h g Z n − 1 ), which outperform the corresponding values of Pt/C-based Zn-air battery. Moreover, 15 light-emitting diodes can be powered by two series-connected Zn-air batteries with Fe 1.2 NC-0.02-800 as the air-cathode catalyst, implying its promising application in clean energy conversion field.
✓ 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）