SENSORS AND ACTUATORS B-CHEMICAL
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2022
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IF 9.221
Muhammad Sohail,Bin Xie,Bingzhi Li,He Huang
The significance of antioxidant activity determination in health sciences and food technology has become a hot research area as it is directly related to oxidative stress which is affiliated with several diseases and food deterioration. Herein, we fabricated a Zn-CDs-based (Zn-doped carbon dots-based) bioanalytical probe for the estimation of antioxidant activity index (AAI) to cope with the truncated robustness, high interference effect in complex samples, photo-bleaching, and low stability of the traditional techniques. Besides, the novel AAI standardized the presentation of the results by considering the transducer, Zn-CDs, concentration as reported results vary diversely for the same sample. In principle, free radicals quenched the fluorescence of the probe via inner filter effect and dynamic quenching. The presence of antioxidants hindered the fluorescence quenching by sequestering the free radicals from the reaction. The designed nanoreagent was validated for its applications using ascorbic acid , human serum, topical cosmetic formulation, and tomato juice samples. The bioanalytical probe demonstrated precise linearity, high robustness, low interference effect, and analytical equivalence when compared to the DPPH free radical assay. Hence, it can be used for the diagnosis and follow-up of oxidative stress-related ailments, developing and characterizing cosmeceuticals, analysis of antioxidant-containing formulations, and assessing and controlling the quality of food products. It is the first report to explore the antioxidant feature of Zn-CDs and its advantage for the estimation of AAI.
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高影响因子
ACS Applied Energy Materials
·
2022
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IF 6.959
Hui Peng,Faqiang Wang,Danyang Wang,Shuzhen Cui,Wenbo Hou,Guofu Ma
Aqueous Zn–MnO2 batteries have received much attention due to their low cost, safety, reliability, and large storage capacity. However, the sluggish ion/electron transport kinetics of bulk MnO2 inevitably decreases the rate capability and cycle stability of Zn–MnO2 batteries. Herein, hierarchical MnO2 nanosheet arrays self-anchored and grown in polyaniline-derived carbon nanotubes (PCNT@MnO2, denoted as PCMO) with enhanced stability are prepared by employing PCNT as both a substrate and a sacrificial reductant. The hollow PCNT conductive skeleton feature and robust integrated MnO2 nanosheet arrays in PCMO are not only favorable for enhancing electronic conductivity and accelerating electronic migration but also provide effective nucleation sites for the growth of MnO2 nanosheets and unimpeded ion channels, resulting in high specific capacity, rapid ion-diffusion kinetics, and long-term cycle stability. Specifically, the optimized PCMO material (PCMO-2) can deliver 264 mAh g–1 at 0.2 A g–1 after 120 cycles without obvious capacity decay, superior to the bare MnO2 material. Moreover, the as-fabricated PCMO//Zn battery can exhibit a high energy density of 320.2 Wh kg–1 at a power density of 120 W kg–1. The rational design of low-cost and integrated core–shell architecture with robust contact between MnO2 nanosheet arrays and a hollow conductive skeleton is expected to achieve cost-effective and high-performance Zn–MnO2 batteries.
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高影响因子
Fundamental Research
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2022
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IF 0
Feng Ma,Xuan Liu,Xiaoming Wang,Jiashun Liang,Jianyu Huang,Cameron Priest,Jinjia Liu,Shuhong Jiao,Tanyuan Wang,Gang Wu,Yunhui Huang,Qing Li
Transition metal supported N-doped carbon (M-N-C) catalysts for oxygen reduction reaction (ORR) are viewed as the promising candidate to replace Pt-group metal (PGM) for proton exchange membrane fuel cells (PEMFCs). However, the stability of M-N-C is extremely challenging due to the demetalation, H 2 O 2 attack, etc. in the strongly oxidative conditions of PEMFCs. In this study, we demonstrate the universal effect of Zn on promoting the stability of atomically dispersed M-N x /C (M = Co, Fe, Mn) catalysts and the enhancement mechanism is unveiled for the first time. The best-performing dual-metal-site Zn-Co-N-C catalyst exhibits a high half-wave potential ( E 1/2 ) value of 0.81 V vs. reversible hydrogen electrode (RHE) in acid and outstanding durability with no activity decay after 15,000 accelerated degradation test (ADT) cycles at 60 °C, surpassing most reported Co-based PGM-free catalysts in acid media. For comparison, the Co-N-C in the absence of Zn suffers from a rapid degradation after ADT due to the demetalation and higher H 2 O 2 yield. X-ray adsorption spectroscopy (XAS) and density functional theory (DFT) calculations suggest the more negative formation energy (by 1.2 eV) and increased charge transfer of Zn-Co dual-site structure compared to Co-N-C could strength the Co-N bonds against the demetalation and the optimized d-band center accounts for the improved ORR kinetics.
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Journal of Materials Chemistry A
·
2022
·Vol. 10
·期 44
·23666-23674
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IF 14.511
Mingna Chu,Yang Li,Ximing Chen,Guangyao Hou,Yan Zhou,Hongjun Kang,Wei Qin,Xiaohong Wu
Solar-driven carbon dioxide (CO2) reduction into valuable chemicals or feedstock is of great significance for the sustainable development of the environment and energy. Herein, we presented a photo-induced reduction method to synthesize catalysts by anchoring Zn single atoms (SAs) on UiO-66-NH2. Impressively, UiO-66-NH2-0.7Zn SAs had excellent performance in converting CO2 to carbon monoxide (CO), which was about a 5-fold improvement compared to pristine UiO-66-NH2 without a photosensitizer or hole sacrificial agent under UV-vis light. The remarkable photocatalytic CO2 reduction performance was attributed to the built-in electric field construction by anchoring highly dispersed Zn SAs on UiO-66-NH2. The built-in electric field could effectively promote the separation of photogenerated charges and activate CO2. Density functional theory (DFT) calculations revealed that low-coordination Zn–N2 sites could dramatically enhance the formation of COOH*, which was the rate-limiting step for CO generation. This study created a new opportunity to develop high-efficiency photocatalysts containing single-atom sites for photocatalytic CO2 reduction.
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高影响因子
CARBON
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2022
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IF 11.307
Chenxi Wang,Jia Chen,Li Zhang,Yaqi Yang,Minghui Huang,Chao Chen,Chunyan Li,Yixi Xie,Pengcheng Zhao,Junjie Fei
In this work, two-dimensional Zn carbon nanosheets (CNs) are obtained after heat treatment of in situ synthesized ZIF-8/NaCl nanocomposites , which are ultrasonically mixed with carboxylated multi-walled carbon nanotubes (MWCNTs). Subsequently, the nanocomposites Zn CNs-MWCNTs with large specific surface area and excellent catalytic properties are obtained. Meanwhile, the photoelectric material H–Cu 2 O/CdTe QDs are drop-coated on Zn CNs-MWCNTs/GCE and the modified electrode Zn CNs-MWCNTs/H–Cu 2 O/CdTe QDs/GCE is obtained. Eventually, a novel dopamine photoelectrochemical sensor based on Zn CNs-MWCNTs/H–Cu 2 O/CdTe QDs/GCE is constructed. Among them, the photocurrent intensity of H–Cu 2 O/CdTe QDs is much higher than that of pure H–Cu 2 O and pure CdTe QDs. This is due to the effective combination of CdTe QDs and H–Cu 2 O to form a p-p heterojunction , which can effectively suppress the recombination of electron-hole pairs. Subsequently, the working mechanism of the photoelectrochemical sensor is investigated in depth by the Kubelka-Munk model. At the same time, the photoelectrochemical sensor has reliable selectivity, stability, reproducibility and limit of detection (LOD = 0.3 nM), and also provides a new idea for the detection of dopamine.
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高影响因子
Journal of Environmental Chemical Engineering
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2022
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IF 7.968
Jiangfu Zheng,Yaocheng Deng,Changzheng Fan,Xiaoming Li,Daoxin Gong,Changwu Li,Ziyi Ye
The construction of an S-scheme heterojunction is an effective way to enhance the photocatalytic activity of composite materials. Thus, a co-precipitation method is combined with a hydrothermal synthesis method in this study to synthesize an S-scheme heterojunction of Bi 2 WO 6 /Ag 3 PO 4 /Zn-Al LDH photocatalyst with an exceptional morphology like a coral reef. On this basis, an AP0.5BWLDH0.3/PMS/Vis reaction system is constructed. The prepared Bi 2 WO 6 /Ag 3 PO 4 /Zn-Al LDH composites present better oxidation performance than pure Bi 2 WO 6 , Zn-Al LDH and Ag 3 PO 4 , with 100% Nitenpyram (50 mg/L) degraded within 90 min due to the photocatalytic activation of peroxymonosulfate. The significant increase in photocatalytic activity is not only due to the uniformly distributed coral reef-shaped nanostructures but also the extended life of the carrier with strong redox capability through S-scheme heterojunction. During the simulated exposure to sunlight, the internal electric field, optimized energy band structure, as well as coulomb force interaction all contributed to the promotion of the transportation of electron-hole pairs in the Bi 2 WO 6 /Ag 3 PO 4 /Zn-Al LDH composite. For this reason, electrons and holes have high reducing and oxidizing properties, which make the composites have high redox capacity. Then the radical trapping experiments, ESR testing and XPS analysis were used to verify these results. It was revealed that the S-scheme heterojunction mechanism was suitable for the electron migration in a photocatalyst. This study extends the design and preparation ideas of new S-scheme heterojunction photocatalysts and then proposes effective strategies to solve future water pollution .
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高影响因子
Journal of CO2 Utilization
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2022
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IF 8.321
Yingjun Li,Ying Chen,Ya-Li Wan,Ren-Shu Wang,Hu Wang,Yi-Zhu Lei
The development of efficient, cost-effective and heterogeneous catalysts for the valorization of CO 2 to high-value chemicals is of vital importance in reducing CO 2 emissions. Herein, single-atom Zn on bipyridine-based porous organic polymer was successfully fabricated through a facile copolymerization of divinyl-bipyridine and divinyl-benzene monomers , followed by complexation with Zn(OAc) 2 . The prepared materials with different concentrations of bipyridine moieties possessed large surface areas, hierarchical porosity, and strong coordination interaction between Zn(OAc) 2 and the polymer scaffold. Catalytic evaluation demonstrated that the optimal single-atom Zn catalyst displayed extremely high catalytic performance towards the N-formylation of amines with CO 2 and PhSiH 3 . Notably, under mild reaction conditions (30 °C, 1 bar CO 2 ), a Zn loading as low as 0.5 mol‰ was sufficient for 94% yield of N-methylformanilide, with a record-high turnover frequency (TOF) of 376 h −1 compared to previously reported heterogeneous catalysts . Moreover, the solid catalyst could be easily recovered and reused for five cycles. Additionally, various amines could be efficiently transformed into corresponding formamide with moderate to high yields. The present work highlights a facile and cost-effective method for constructing highly efficient and recyclable single-atom metal catalysts for N-formylation of amines with CO 2 .
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高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2022
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IF 6.371
Chunxia Yan,Shuai Jia,Jie Wei,Ziqiang Shao
Porous carbon aerogels derived from abundant biomass, which possess a unique structure, a high specific surface area and heteroatom doping, are a promising electrodes material for supercapacitors (SCs). In this study, an innovative hierarchical porous material comprising cobalt decorated porous carbons derived from cellulose nanofiber / graphene / Zn/Co ZIF carbon aerogels (CRZCs) has been successfully synthesized by directional freeze drying and carbonization methods. Cellulose nanofibers (CNFs) and graphene (rGO) layers play not only a supporting role, but also an internal storage site for electrolytes, contributing to the diffusion of electrolytes to the surface of active substances, at the same time enhance hydrophilicity of the aerogel and contribute to uniformly disperse Zn/Co ZIF. What's more important is that the carbon aerogels possess hierarchical porous involving micropores, mesopores and macropores, which further aid electrolyte penetration and ion storage. Furthermore, benefiting from the synergetic effect of hierarchical porous, high surface area, high conductivity, the prepared CRZC electrode obtains a high specific capacitance (364.6 F g −1 at 1 A g −1 ), an extraordinary capacitance retention rate (83.4 % at 10 A g −1 ). Simultaneously, the assembled supercapacitor by CRZC 900 exhibits a high specific capacitance (121.4 F g −1 at 0.5 A g −1 ), good charging/discharging rates, and remarkable cycling stability (78.9 % capacitance retention over 10000 cycles). The energy density up to 18.9 Wh kg −1 is achieved at power density of 288.4 W kg −1 , indicating its comprehensive applicability in energy storage. Finally, our results provide a general approach to construct hierarchical porous carbon aerogels for high-performance supercapacitors.
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高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2022
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IF 24.319
Wen Wen Xie,Tong Zhen Tian,Min Yang,Nian Wu Li,Le Yu
Rational design of effective bifunctional inexpensive oxygen electrocatalyst is highly important for Zn-air batteries (ZABs), which can accelerate both oxygen reduction/evolution reactions at the oxygen electrode. Herein, we present the formation of hierarchical hollow frameworks of dual-sided Fe/Fe 3 C@N-doped carbon nanotubes (FNCHFs) through a template-engaged method. Benefitting from the synergistic effect between the robust hollow frameworks and in-situ grown dual-sided N-doped carbon nanotubes, the FNCHF electrocatalyst presents enhanced mass/electron transport with high structural stability. As a result, the FNCHFs based bifunctional oxygen electrode demonstrates a desirable oxygen electrocatalytic activity and stability with a half-wave potential of 0.863 V for oxygen reduction and an overpotential of 340 mV to reach the current density of 10 mA cm −2 for oxygen evolution. The corresponding ZAB exhibits a high peak power density of 206 mW cm −2 , a high specific capacity of 781 mAh g Zn −1 , and a good cycling stability more than 300 h.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2021
·Vol. 139
·期 17
·52041
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IF 3.125
Zhiyuan Song,Jie Wang,Qian Tao,Yang Yu,Hui Zhang,Chuanqun Hu,Hongyu Cen,Xuan Zheng,Tao Hu,Chonggang Wu
Zn-salt poly(styrene– ran –cinnamic acid) (SCA–Zn) ionomers were successfully synthesized via the melt neutralization of poly(styrene– ran –cinnamic acid) (SCA), which has a comparable molecular weight ( = 217,000) to commercial polystyrene (PS), with different mass fractions of ZnO (0.62, 1.6, and 3.9 wt.%) and the successful synthesis was confirmed by Fourier transform infrared spectroscopy. The mechanical properties, heat resistance, and processibility of the PS, SCA, and SCA–Zn samples were characterized. Compared to SCA, the three SCA–Zn ionomers exhibited significantly higher α cN values, with the ionomers containing 1.6 and 3.9 wt.% ZnO were 11.4% and 68.6% higher than that of SCA, respectively. Compared to commercial PS, SCA–Zn also exhibited significant improvements in heat resistance (glass transition temperature and vicat softening temperature both improved by about 20 °C) and impact toughness ( α cN values of the ionomers containing 1.6 and 3.9 wt.% ZnO were 69.6% and 156.5% higher than that of PS), while the processability of SCA–Zn was not significantly worse than that of PS. This method efficiently improves both the toughness and heat resistance of PS, providing an efficient way to expand the market application of styrenic resins.
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高影响因子
JOURNAL OF FOOD QUALITY
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2021
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IF 2.45
Tingting Liu,Shanshan Zhang,Nan Wang,Xinle Xu,Hongcheng Liu,Dawei Wang,Yanrong Zhang
With Auricularia cornea Ehrenb polysaccharide (ACEP) as raw material, the purpose of the study was to prepare Auricularia cornea Ehrenb polysaccharide-zinc (ACEP-Zn) complex. Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), nuclear magnetic resonance (NMR), and other means are used to analyze the physical-chemical properties and structure of ACEP and ACEP-Zn, to investigate the inhibition of α-glycosidase and α-amylase enzymes, and to explore its effects on the glucose metabolism of insulin-resistant HepG2 cells. Nuclear magnetic resonance (NMR) results show that a group of COO-, -CH3, and -OH in the sugar chain binds to Zn2+. Compared with the original polysaccharides, the surface morphology of ACEP-Zn changed obviously, and the molecular weight (Mn) of ACEP-Zn decreased, but the molecular agglomeration of ACEP-Zn increased. Moreover, the inhibitory effect of ACEP-Zn on α-glucosidase and α-amylase was stronger than that of the original polysaccharide. The results indicated that the structure of Auricularia cornea Ehrenb polysaccharide was changed obviously after the zinc complex, and its hypoglycemic activity was enhanced in vitro. In the cell experiment, the glucose consumption of IR-HepG2 cells was significantly increased at a concentration of 50–200 μg/mL (). The activity of SOD and NOS significantly increased (), and the activity of intracellular PK increased (). Therefore, it was speculated that the hypoglycemic effect of Auricularia cornea Ehrenb polysaccharide combined with zinc was related to the alleviation of liver cell damage caused by oxidative stress and the improvement of glucose metabolism of IR-HepG2 cells. The study provides a theoretical basis for the application of the polysaccharide-zinc complex in the hypoglycemic functional food field.
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高影响因子
CRYSTENGCOMM
·
2021
·Vol. 23
·期 39
·6899-6908
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IF 3.545
Huimin Wang,Tingting Wang,Zibin Huang,Yizhuo Liu,Dehui Leng,Junli Wang
The growth of metal chalcogenide nanowires (NWs) on metal substrates is challenging work since the direct reactions taking place between the chalcogen (S, Se or Te) and zero-valent metal (M0) are frequently unable to regulate the crystallization of nanocrystals in an anisotropic one-dimensional (1D) manner. We here report the use of Ag2Se seeds as catalyst particles to realize the growth of metal selenide (MSe) NWs on their respective metal foil or flakes, including ZnSe/Zn, CdSe/Cd, and MnSe/Mn material systems. Metal foil or flakes (M = Zn, Cd and Mn) serve as a support substrate as well as a metal cation source during the NW synthesis. The preformed Ag2Se seeds play the roles of not only catalytic particles that initiate a so-called solution–solid–solid process to produce crystalline MSe NWs on metal substrates, but also inert impurities that promote an electrochemical anodic reaction of the metal to supply metal cations (M0 − 2e → M2+) for the NW formation. The microstructural studies by HRTEM reveal the polytypism and particularly the diameter-dependence of crystal phases and growth directions in the resulting MSe NWs, which can be rationalized from the viewpoints of the energetics and the catalyst/NW interfacial structures. These semiconductor NWs grown on metal foil or flakes may find wide use in photoelectric catalysis and devices without a transfer process of free-standing NWs onto a conductive support substrate.
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高影响因子
危险品化学品经营许可证（带存储）