Journal of the American Chemical Society
·
2014
·
IF 11.444
Xibin Pang,Wei Chang,Chuncheng Chen,Hongwei Ji,Wanhong Ma,Jincai Zhao
The molecules O2 and H2O dominate the cleavage of aromatic sp2 C–C bonds, a crucial step in the degradation of aromatic pollutants in aqueous TiO2 photocatalysis, but their precise roles in this process have remained elusive. This can be attributed to the complex oxidative species involved and to a lack of available models for reactions with a high yield of direct products. Here, we used oxygen-18 isotope labeled O2 and H2O to observe the aromatic ring-opening reaction of the model compound 3,5-di-tert-butylcatechol (DTBC), which was mediated by TiO2 photocatalysis in an aqueous acetonitrile solution. By analyzing the primary intermediate products (∼75% yield), especially the seven-membered ring anhydrides that were formed, we obtained direct evidence for the oxygen atom of dioxygen insertion into a C–C bond of the aromatic ring. This indicates that molecular oxygen is the ultimate ring-opening agent in TiO2 photocatalysis and that it undergoes single O atom incorporation rather than the previously proposed molecular oxygen 1,2-addition processes. The ratio of intradiol to extradiol products depends on the particle size of TiO2 catalysts used, which suggests that the O2 activation is correlated with the available coordination sites on the TiO2 surface in the photocatalytic cleavage of the aromatic ring.
研究领域:
环境科学
·
化学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Shumin Li,Jun Tan,Zhejun Jiang,Jin Wang,Zhengquan Li
Dye-sensitized systems show promising in photocatalysis because they can separate the tasks of light absorption, charge generation and surface catalysis to two coupled components. In this system, it is crucial to develop suitable catalysts capable of receiving dye-injected charges and having high activity to a given reaction. Aiming to photocatalytic H 2 and O 2 production, we present a metal-organic framework derived route to prepare bimetallic Fe-Ni-P nanotubes using Fe-Ni-MIL-88 nanorods as templates. When integrated with different dyes, these Fe-Ni-P nanotubes can serve as efficient catalysts for photocatalytic H 2 and O 2 production, respectively. Additionally, catalytic activities of such dye-sensitized systems can be conveniently regulated by tailoring the metal compositions in Fe-Ni-P nanotubes. The photocatalytic H 2 production of Fe 1 -Ni 2 -P can reach 5420 μmol g cat −1 h −1 under eosin-Y sensitization, which is 24 times and 6.7 times higher than Fe 2 P and Ni 2 P, respectively. The photocatalytic O 2 production of Fe 1 -Ni 2 -P can reach 900.3 μmol g cat −1 h −1 under [Ru(bpy) 3 ]Cl 2 sensitization, about 4.6 times and 2.9 times higher than Fe 2 P and Ni 2 P. The roles of different components in the system have been explored and corresponding working mechanism is proposed. This work demonstrates a new type of dye-sensitized systems consisting of bimetallic phosphides and provides a facile route to regulate their photocatalytic performance.
研究领域:
材料科学
·
光催化
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高影响因子
Journal of Materials Chemistry A
·
2016
·Vol. 4
·期 25
·10008-10013
·
IF 8.262
Jin-ling Ma,Xin-bo Zhang
Development of an efficient air cathode for metal–air batteries composed of an element that is abundant on earth is a scientific and technical challenge. Here, nitrogen (N)-doped carbon cathodes were prepared using two conventional doping methods, namely ammonia activation (ammoxidation) and introduction of an N-containing precursor. Interestingly, the introduction of N-containing precursors to prepare the N-doped carbon material not only gave a different pore distribution with increased surface area but also maintained considerable N content, unlike the use of the ammoxidation method – thus greatly enhancing the catalytic activity (low overpotential) and improving the discharge capacity (6905 mA h g−1) and cycle life (from 8 to 66 cycles) in sodium–oxygen batteries compared with the pure carbon material. This study also stresses the importance of adopting the optimized synthesis method to prepare the N-doped carbon cathode.
研究领域:
电化学
·
能源材料
·
纳米材料
·
电池技术
·
多孔材料科学
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DOI
高影响因子
MATERIALS LETTERS
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2018
·
IF 2.687
Yu Wang,Xingbao Zhu,Yingzhang Yan,Weihua Wan,Yuanguo Wu,Xin Ji,Zhe Lü
Actually, Li-O 2 batteries can be served as flexible power sources with extremely high specific energy densities to meet the rising demand for flexible and wearable electronic devices. In this work, the electrochemical performance and flexibility of a Li-O 2 battery are demonstrated to be significantly enhanced by introducing a KH550–NH 4 Cl-treated, KOH-activated, CNTs-grafted cotton fabrics cathode. The as-fabricated flexible cathode exhibits superior electrochemical performance, including a high specific capacity (22.4 mAh cm −2 at 0.15 mA cm −2 ), an excellent rate capability, and a good cyclic performance for more than 250 cycles.
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米材料
·
柔性电子器件
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DOI
高影响因子
Small
·
2018
·Vol. 14
·期 34
·1801798
·
IF 9.598
Xiaohong Zou,Qian Lu,Yijun Zhong,Kaiming Liao,Wei Zhou,Zongping Shao
Gel-polymer electrolytes are considered as a promising candidate for replacing the liquid electrolytes to address the safety concerns in Li–O 2 /air batteries. In this work, by taking advantage of the hydrogen bond between thermoplastic polyurethane and aerogel SiO 2 in gel polymer, a highly crosslinked quasi-solid electrolyte (FST-GPE) with multifeatures of high ionic conductivity, high mechanical flexibility, favorable flame resistance, and excellent Li dendrite impermeability is developed. The resulting gel-polymer Li–O 2 /air batteries possess high reaction kinetics and stabilities due to the unique electrode–electrolyte interface and fast O 2 diffusion in cathode, which can achieve up to 250 discharge–charge cycles (over 1000 h) in oxygen gas. Under ambient air atmosphere, excellent performances are observed for coin-type cells over 20 days and for prototype cells working under extreme bending conditions. Moreover, the FST-GPE electrolyte also exhibits durability to protect against fire, dendritic Li, and H 2 O attack, demonstrating great potential for the design of practical Li–O 2 /air batteries.
研究领域:
电化学能源
·
材料科学
·
纳米复合材料
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先进电池技术
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固态离子学
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DOI
高影响因子
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Qin Zhao,Yuhang Zhang,Guiru Sun,Lina Cong,Liqun Sun,Haiming Xie,Jia Liu
Developing a long-term stable electrolyte is one of the most enormous challenges for Li–O2 batteries. Equally, the high flammability of frequently used solvents seriously weakens the electrolyte safety in Li–O2 batteries, which inevitably restricts their commercial applications. Here, a binary mixture of highly concentrated tetraglyme electrolyte (HCG4) and 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether (TTE) was used for a novel electrolyte (HCG4/TTE) in Li–O2 batteries, which exhibit good wettability, enhanced ionic conductivity, considerable nonflammability, and high electrochemical stability. Being a co-solvent, TTE can contribute to increasing ionic conductivity and to improving flame retardance of the as-prepared electrolyte. The cell with this novel electrolyte displays an enhanced cycling stability, resulting from the high electrochemical stability during cycling and the formation of electrochemically stable interfaces prevents parasitic reactions occurring on the Li anode. These results presented here demonstrate a novel electrolyte with a high electrochemical stability and considerable safety for Li–O2 batteries.
研究领域:
储能
·
电化学
·
材料科学
·
电池技术
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高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2021
·Vol. 105
·期 4
·2690-2701
·
IF 3.784
Lu Zou,Zhao Lu,Ziling Wang,Bo Chi,Jian Pu
Developing high-efficiency and cost-effective bifunctional electrocatalysts toward the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is an urgent issue for the oxygen-based electrochemical devices. Herein, an interface engineering concept has been proposed to achieve high-performance Ag–PBSC (Ag–PrBa 0.5 Sr 0.5 Co 2 O 5+δ ) heterostructure nanofibers catalyst. Benefiting from the significant ligand action and interparticle cooperation of exsolved Ag NPs and PBSC double perovskite, ORR/OER catalytic kinetics have been successfully boosted. In details, the PBSC double perovskite possessing abundant oxygen vacancies can provide oxygen channels and facilitate the transfer of electrons and oxygen. The embedded Ag NPs can deliver superior catalytic durability for the heterostructure interface. As expected, the as-synthesized Ag-PBSC heterostructure catalyst performs a favorable electrochemical performance in the oxygen-based applications. In alkaline media, the catalyst exhibits an excellent activity for ORR ( E onset : 0.88 V vs. RHE and E 1/2 : 0.72 V vs. RHE) and OER (1.67 V at 10 mA cm –2 ). When adopting the Ag–PBSC heterostructure catalyst in LOBs, the corresponding battery provides an outperforming capacity performance (13 000 mAh g –1 ), low discharge–charge polarization (1.37 V), and considerable cycling performance (128 cycles at the restricted capacity of 3 000 mAh g –1 and 400 mA g –1 ). Apparently, the work described here confirms that the interface engineering of perovskites can open up opportunities to develop highly active and durable heterostructure electrocatalysts for multitudinous oxygen-based electrochemical applications.
研究领域:
材料科学
·
电化学
·
能源存储与转换
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高影响因子
RARE METALS
·
2026
·Vol. 45
·期 8
·e70484
·
IF 12.1
Ying Li,Guiru Sun,Dandan Wang,Daming Yang,Qi Mi,Xinru Wang,Dongxu Yin,Baoxin Ni,Wei Lu,Ming Feng
en This link goes to a English section zh This link goes to a Chinese section Li–O 2 batteries garner widespread attention owing to their remarkable theoretical specific capacity. Nevertheless, the feasible implementation of the system is hindered by sluggish cathode reaction kinetics and poor anode stability. Herein, the carbon dots (CDs) with -OH, -NH 2 , and -COOH groups are synthesized and employed as electrolyte additives for Li–O 2 batteries. The CDs are well-dispersed in the electrolyte which promotes the formation of Li 2 O 2 through hydrogen bond-mediated dissolution, whereas their high catalytic activity simultaneously facilitates Li 2 O 2 decomposition, thereby enhancing cathode reaction kinetics. Additionally, CDs can suppress dendrite growth on the Li anode and reduce dead Li accumulation by improving the properties of the electrolyte, including ionic conductivity, raising the Li + transference number, ensuring strong electronic insulation, and altering the Li + solvation structure. Therefore, the introduction of CDs enables the Li–O 2 battery to achieve a discharge capacity of 5422.2 mAh g −1 and maintain stable cycling performance of 700 h at 100 mA g −1 . This work underscores the remarkable efficacy of CDs electrolyte additive in enhancing the performance of the Li–O 2 battery, providing a new direction for addressing existing challenges of the battery. 摘要 en This link goes to a English section zh This link goes to a Chinese section 锂氧电池因其超高的理论比容量而备受关注,但受限于正极反应动力学迟缓、锂负极稳定性差等问题,其实际应用仍面临挑战。为此,本研究合成了羟基、氨基与羧基官能团修饰的碳点,并将其用作锂氧气电池电解液添加剂。该碳点在电解液中分散性良好,能够通过氢键作用促进过氧化锂 (Li 2 O 2 ) 的形成; 同时,其自身优异的催化活性可加速 Li 2 O 2 的分解,从而有效提升正极反应动力学。此外,碳点的引入可优化电解液的多个关键性能,包括提高离子电导率、增大锂离子迁移数、保持良好的电子绝缘性,并调控锂离子溶剂化结构,进而抑制锂负极的枝晶生长、减少死锂积累。基于以上作用,引入碳点的锂氧电池在 100 mA g −1 电流密度下,放电比容量达到 5422.2 mAh g −1 ,并实现了长达700小时的稳定循环。本研究证实了功能化碳点作为电解液添加剂对提升锂氧电池性能的显著作用,为解决该体系现存的关键问题提供了新思路。
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产品关联
DOI
高影响因子
ADVANCED MATERIALS
·
2026
·
IF 29.1
Da-Shuai Huang,Yi Tang,Pei-Qin Liao,Xiao-Ming Chen
Electrochemical CO 2 reduction must move beyond purified CO 2 to use real-world sources like flue gas or captured CO 2 . But such low-concentration feeds pose two problems: residual O 2 poisons the reaction, triggering competing oxygen reduction reaction, cutting carbon efficiency, and degrading the catalyst, while low CO 2 concentration limits mass transfer and conversion. We solve both with a kinetic molecular sieve: polyethylene glycol-coated bismuth nanoparticles (Bi@PEG). Under simulated flue gas (15% CO 2 , 5% O 2 , 80% N 2 ), Bi@PEG demonstrates record-breaking performance for CO 2 electroreduction to formate, achieving a Faradaic efficiency of 94.1 ± 0.6%, a current density of 0.91 A·cm −2 , and a single-pass CO 2 conversion of 72.5%, and maintains this performance even at 8% O 2 . Mechanism studies show the PEG layer selectively admits CO 2 (small size, quadrupole moment, strong Lewis acid, base interaction with ether oxygens; binding energy −27.4 kJ mol −1 ; diffusion barrier 0.57 eV), resulting in interfacial CO 2 enrichment. In contrast, O 2 transport is significantly impeded due to a higher diffusion barrier (0.83 eV), weak binding affinity (−3.0 kJ mol −1 ), and steric hindrance. By overcoming the dual challenges of low CO 2 concentration and oxygen interference, this work establishes “armored catalysis” as a universal approach for electrochemical CO 2 conversion using realistic, low-concentration, oxygen-containing carbon sources.
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2026
·Vol. 46
·期 16
·118716
·
IF 6.3
Quan Han,Yuhuan Ji,Yang Liu,Caiyun Wang,Kechun Shen,Yi Zhang,Chao Ma,Hailong Wang,Daoyang Han,Gang Shao
Fabricating high-performance high-entropy ceramics (HECs) with complex geometries remains a challenge. Here, high-entropy fluorite (Ce 0.2 Zr 0.2 Ti 0.2 Sn 0.2 Ca 0.2 )O 2-δ ceramics were fabricated by digital light processing (DLP). The effects of slurry solid loading (76–80 wt%) on sintering behavior, microstructure, mechanical properties, and thermal transport were systematically investigated and compared with pressureless sintering. Increasing the solid loading to 80 wt% increased the green-body density, reduced linear shrinkage, and produced ceramics with a bulk density exceeding 5.0 g/cm³ (>88% theoretical density). EDS analyses revealed compositionally homogeneous microstructures without detectable micron-scale elemental segregation within the spatial resolution of the present measurements. DLP-80 HEFO exhibited the highest flexural and compressive strengths among the printed samples while maintaining low thermal conductivity values of 1.7–2.2 W·m⁻¹ ·K⁻¹ from 25 to 1000 °C. This work demonstrates that optimizing slurry solid loading provides an effective strategy for fabricating high-entropy fluorite ceramics with balanced densification, mechanical performance, and thermal-insulation capability.
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2026
·
IF 12.5
Wangjie Chu,Shengkai Ke,Kexin Feng,Weizhen Xie,Zecui Sheng,Lu Lin,Xing Tang
Base-regulated ROS strategy enables mild HMF-to-FDCA oxidation. • NaHCO 3 stabilizes ·O 2 − ; NaOH promotes ·O 2 − /·OH synergy. • NaOH system drives O 2 relay: O 2 → ·O 2 − → H 2 O 2 → ·OH for FDCA synthesis. The sustainable conversion of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) via aerobic oxidation is a cornerstone of future biorefinery, yet its practical implementation under mild conditions is constrained by the spin-forbidden activation of triplet O 2 . In this work, we report a base-regulated reactive oxygen species (ROS) strategy that enables efficient HMF oxidation to FDCA at low temperatures (30–60 °C) under ambient oxygen pressure. We find that weak base NaHCO 3 selectively stabilizes ·O 2 − , directing a selective oxidation pathway, whereas strong base NaOH promotes a synergistic ·O 2 − /·OH mechanism that substantially accelerates the overall reaction. Through careful optimization, a 95.8% FDCA yield is obtained under ambient O 2 flow. Kinetic analysis, including reaction order determination and kinetic isotope effect measurements, demonstrates that O 2 activation is the rate-limiting step in the NaOH system, following a relay activation pathway of O 2 → ·O 2 − → H 2 O 2 → ·OH. This work not only elucidates the mechanistic role of bases in regulating ROS during HMF oxidation but also provides a practical and green route for synthesizing FDCA under mild, ambient-pressure conditions, advancing the field of sustainable biomass conversion. This work demonstrates a base-regulated reactive oxygen species (ROS) strategy for the mild oxidation of HMF to FDCA. The weak base NaHCO 3 selectively stabilizes ·O 2 − , directing a selective oxidation pathway, whereas the strong base NaOH promotes synergistic ·O 2 − /·OH participation, substantially accelerating the reaction. Mechanistic studies reveal that O 2 activation follows a relay pathway: O 2 → ·O 2 − → H 2 O 2 → ·OH in the NaOH system. Under ambient oxygen pressure and at 30–60 °C, a 95.8% FDCA yield is achieved, offering a new route for green biomass conversion. Download: Download high-res image (47KB) Download: Download full-size image
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高影响因子
Frontiers in Energy Research
·
2026
·
IF 2.4
Ming Pan,Hao Gao,Xiaotong Zhang,Qingfu Yang
In oil-immersed transformers, cellulose insulating paper deteriorates when exposed to electric field, moisture, and high temperature for a long time, leading to decrease in mechanical strength and insulating performance, which affects the service life and operational reliability. In this paper, dielectric barrier discharge (DBD) is adopted to generate atmospheric pressure low-temperature plasma for the treatment of cellulose insulating paper with Octamethylcyclotetrasiloxane (OMCTS)/O2 as the reaction medium. The influences of medium flow rate and treatment time on the comprehensive performance of insulating paper are investigated to obtain optimal treatment effect. The results show that the water resistance, breakdown strength, and mechanical strength of the modified insulating paper are significantly improved. Under optimal conditions, the surface wettability of the insulating paper changes from hydrophilic to hydrophobic (with a water contact angle exceeding 150°), and the water absorption rate is reduced by 57.1%. Meanwhile, the breakdown strength is increased by 41.9%, and the maximum stress is increased by 31.5%. After plasma modification, a 44.8% improvement in the breakdown strength of the oil-impregnated paper is achieved. Combined with the characterization of physicochemical properties such as SEM, EDS, and FTIR, it is found that the low-polarity Si–O–Si and Si–CHx fragments, generated by the plasma, not only form a dense film on the paper surface, but also are deposited inside the bulk. This process reduces surface polarity, fills air gaps, and introduces deep traps, thereby realizing the improvement of the comprehensive performance of the insulating paper.
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高影响因子