NEW JOURNAL OF CHEMISTRY
·
2022
·Vol. 46
·期 30
·14510-14516
·
IF 3.925
Yunxian Zhang,Yongyu Pang,Dong Xia,Guoliang Chai
As a successful alternative to the complex and dangerous anthraquinone process, a simple and safe method for the efficient preparation of hydrogen peroxide is to use the electrochemical two-electron oxygen reduction reaction (2e− ORR) process. Herein, we report a facile approach to achieving metal-free nitrogen-doped carbon material electrocatalysts (N-CMCs) using cheap and easily available raw materials, which also have an excellent electrochemical 2e− ORR catalytic performance and selectivity for hydrogen peroxide (H2O2). The as-fabricated nitrogen-doped carbon material electrocatalysts (named as N-CMC-1 : 5) deliver the high H2O2 selectivity of over 80% in a wide potential range from 0.30 to 0.70 V vs. RHE, where the highest H2O2 selectivity can reach 81.4% at 0.42 V vs. RHE. X-ray photoelectron spectroscopy and electrochemical analyses reveal that the content of pyrrolic-N in the catalysts has a positive effect on the 2e− ORR activity. When the catalyst contains more pyrrolic-N, the catalyst demonstrates a better 2e− ORR performance and H2O2 selectivity in alkaline medium, as well as the long-term stability of the catalyst.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2022
·Vol. 28
·期 68
·e202202004
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IF 5.02
Conghui Zhao,Liwei Sun,Yang Xu,Beibei Dong,Yuhong Luo,Jingde Li,Jianxin Chen,Zisheng Zhang
Graphical Iodine-doped Bi 2 GdO 4 Cl with a significantly promoted visible-light-responsive O 2 -evolving performance of 154.8 μmol ⋅ h −1 and an apparent quantum efficiency of ∼1.1 % at 420 nm is reported. The incorporation of I − ions causes the extended light absorption and promoted charge separation. Visible-light-responsive bismuth-based oxyhalide has recently attracted extensive attention, however, the promotion of its charge separation is still challenging. Herein, we introduce iodine into Bi 2 GdO 4 Cl to synthetize I-doped Bi 2 GdO 4 Cl (denoted as yI−Bi 2 GdO 4 Cl, 0≤y≤2). The incorporation of I − ions is found to enhance light absorption and to accelerate charge separation by combining various characterizations such as density functional theory calculation, photoelectrochemical test, electrochemical impedance spectroscopy, photoluminescence spectrum, and open-circuit voltage decay. The O 2 -evolving performances of 1I−Bi 2 GdO 4 Cl with optimized dopant concentration of I − ion and IrO 2 loaded 1I−Bi 2 GdO 4 Cl are tremendously enhanced by ca. 4 and 45 times compared to pristine Bi 2 GdO 4 Cl. Notably, The O 2 evolution rate reaches as high as 154.8 μmol ⋅ h −1 with an apparent quantum efficiency of ∼1.1 % at 420 nm. The synthetic iodine-doped photocatalyst remains stable after long-term photoreaction, demonstrating its potential in the field of photocatalysis.
研究领域:
材料科学
·
光催化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2022
·
IF 24.319
Weijie Yang,Kailong Sun,Jun Wan,Yang-Ai Ma,Jiaqing Liu,Bicheng Zhu,Lin Liu,Feng Fu
The insufficient generation of oxidative active species severely limits the activity of photocatalytic aerobic oxidation for organic pollutants degradation in wastewater. Herein, transition metal phosphides (TMPs) cocatalysts, including Ni 2 P, Co 2 P, and NiCoP, were loaded on Bi 4 O 5 Br 2 nanosheets by a simple liquid assembly method. Among which, 15% NiCoP/Bi 4 O 5 Br 2 heterojunction exhibits the optimal photocatalytic activity for degrading phenolic pollutants owing to the high concentration of h + and •O 2 − active species, and it displays excellent tolerance for the inorganic ions, pH value, water matrix, and outdoor sunlight. The S-scheme charge transfer mechanism was revealed for NiCoP/Bi 4 O 5 Br 2 heterojunction, which significantly improves the separation efficiency of photogenerated charge carriers and facilitates the accumulation of active h + . Furthermore, NiCoP with high reduction potential and outstanding O 2 activation ability is served as the active site for producing •O 2 − . This work can inspire the further design of bifunctional photocatalysts for efficient photocatalytic aerobic oxidation applications.
研究领域:
环境科学
·
材料科学
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产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2022
·
IF 24.319
Zhaomin Chen,Zhenyu Wu,Jia Xu,Rui Zhao,Xiaoxia Han,Jiwei Jiang,Mingwang Shao,Bin Dong,Zhenhui Kang
Photochemical devices show great potential in applications ranging from electrical energy storage to future smart grids. Here, we report a metal-free composite film cell based on carbon dots (CDots) and polyaniline (PANI), which could achieve 24/7 discharge and photo-charging in seawater. CDots/PANI film cell has an open-circuit-voltage (OCV) of 0.95 V, a maximum power density of 380 mW m 2 , and the ability to discharge continuously for 40 h under solar irradiation of AM 1.5 G. It couples the reduction reaction of PANI, and the CDot-catalyzed oxygen reduction reactions (ORR) during discharge. While the light-induced CDot-catalyzed oxygen evolution reaction (OER) and the reduction reaction of PANI during charging. In particular, in-situ TPV tests were used to verify the effect of the light-induced OER and the kinetic properties of the catalyst on the charge transfer at the interface. We believe this research may provide new ideas for sustainable energy conversion and storage.
研究领域:
材料科学
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能源转换与存储
·
光化学
✓ 已验证
产品关联
DOI
高影响因子
Energy Storage Materials
·
2021
·
IF 17.789
Xiaowei Mu,Chao Xia,Bin Gao,Shuyi Guo,Xueping Zhang,Jianping He,Yonggang Wang,Hao Dong,Ping He,Haoshen Zhou
Rechargeable Li-O 2 batteries have captured increasing attention owing to their ultra-high theoretical specific energy. However, this promising system is confronted with the large overpotential, limited discharge capacity and low cyclic life. Herein, three two-dimensional (2D) molybdenum-based compounds of MoN, MoO 3 and MoS 2 are used as cathode catalysts in Li-O 2 batteries . The catalytic performance and electronic structures of these catalysts are compared comprehensively. Electrochemical test results reveal the superior battery performance of MoN cathodes, which deliver the highest specific discharge capacity of approximately 7400 mAh g − 1 and the lowest discharge/charge overpotential of 0.19/0.72 V. Density functional theory (DFT) calculations demonstrate the metallic property of MoN whereas MoO 3 and MoS 2 are poor conductive. Besides, interface properties between MoN and Li 2 O 2 products as well as reaction pathways of the Li-O 2 battery with MoN cathode are also investigated detailedly by DFT calculations, explaining the excellent catalytic properties of MoN at the atomic level. The present work provides intrinsic insights into designing high-performance cathode catalysts for Li-O 2 batteries with fine-tuned morphology and electronic characteristics.
研究领域:
材料科学
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电化学
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电池技术
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催化
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理论化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Shuzhen Yu,Yongchun Hou,Qijie Jin,Liangliang Zhu,Su Chen
As global warming and greenhouse gas emissions intensify, the scientific community is continuingly seeking effective solutions. One promising strategy known as artificial photosynthesis is proposed utilizing H 2 O as a reducing agent to transfer CO 2 into fuel. However, low O 2 production and conversion efficiency have hindered this approach in matching with natural photosynthesis. In this work, we propose a novel biomimetic photocatalyst design approach to improve the catalytic efficiency by slow photon mechanism. Our design is mainly inspired by two factors: 1) Chlorophyll, an abundant natural photosynthetic pigment, can efficiently and selectively reduce carbon dioxide and plays a key role in photosynthesis; 2) The iridoplast with a biological photonic crystal structure can significantly improve the efficiency of photosynthesis. Specifically, we couple photonic crystals and photocatalyst of sodium copper chlorophyllin (ChlCu), and binder of PVA through microfluidic blowing-spinning (MBS) to spray a composite photocatalytic film that can convert carbon dioxide and water into carbon monoxide and oxygen. By optimizing the content of ChlCu and the slow photon effect related to the bandgap position, the final CLPPs 300 -0.52% has two slow photon edges overlapping with the catalyst absorption spectrum, thus generating the maximum photon capture capability and achieving a high oxygen catalytic yield of up to 7.8 mmol g -1 h −1 . The spraying property of this material enable it to be coated on the external surfaces of other materials. This opens new possibilities of photocatalytic fabric preparation for CO 2 converting, providing new ideas of greenhouse gas capture and utilization to solve environmental problems.
研究领域:
环境科学
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材料科学
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光合作用研究
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Weixue Yang,Jiaqi Zhao,Zhen Li,Jiayu Xin,Fei Li,Yu Wang
Introducing light energy into the charging/discharging process is an effective strategy to reduce the overpotential of Li−O 2 battery, which leads that the battery has higher energy conversion efficiency and better battery performance. However, the development has been hampered by the lack of suitable photocatalysts and cathode structure to accommodate the insoluble Li 2 O 2 . In order to overcome the aforementioned difficulties, a bifunctional photocatalyst α-Fe 2 O 3 /SnO 2 (FS) heterojunction was designed as the cathode to improve the charging/discharging overpotentials simultaneously. The photogenerated electrons and holes from FS participated in the oxygen reduction reaction (ORR) and oxygen revolution reaction (OER) under illumination, giving rise to an ultra-low charging/discharging overpotential of 0.01 V (energy efficiency up to 99.7%), which improved the electrochemical reaction kinetics of the Li−O 2 battery strikingly. In addition, the FS cathode exhibited excellent cycle stability under light (the battery energy efficiency can still maintain 80% after 252 cycles). The bifunctional catalyst designed in this paper has profoundly proved that the band engineering strategy can effectively utilize solar energy and provide important insights for understanding the mechanism of photo-assisted Li−O 2 battery.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
TRANSACTIONS OF TIANJIN UNIVERSITY
·
2025
·Vol. 31
·期 3
·278-291
·
IF 8.5
Chi Shuxiu,Wang Chenhui,Liao Jie,Sun Peng,Fei Yaohan,Han You,Zhang Jinli,Wu Jiangjiexing,Li Wei
Aiming at inhibiting the irreversible P2–O2 phase transition of conventional P2-type cathode materials at high voltage and enhancing the cycling stability of sodium-ion batteries, in this article, based on a strategy of adjusting the Na + ion occupancy within the crystal structure, Na 0.67 Ni 0.33 Mn 0.67– x Fe x O 2 (NM– x Fe, x = 0.10, 0.15, 0.20) cathode materials were synthesized by high shear mixer (HSM)-assisted co-precipitation method and evaluated the electrochemical performance at high voltage (4.35 V). The optimal sample NM–0.15Fe exhibits an initial discharge capacity of 130.8 mAh/g (0.1 C), with exceptional retention of 95.9% after 100 cycles (1 C). XRD analysis reveals that Fe intercalation promotes the more amount of Nae-similar occupation; the Nae/Naf ratio equals 1.93 for NM–0.15Fe versus 1.62 for NM, which enhances Na + diffusion kinetics, as confirmed by GITT tests. Through characterizations of in situ XRD, XPS, HRTEM, CV, etc., it is illustrated that the Fe 3+ intercalation can effectively disrupt the Na + /vacancy ordering and inhibit the harmful P2–O2 phase transition, and then improve the cycling stability of the cathode. DFT calculations disclose that intercalated Fe can reduce the electron densities of adjacent transition metallic elements, generating more repulsive forces impacted on sodium and consequently appearance of more Nae sites, leading to a lower Na + diffusion energy barrier. Such strategy of modulating Na occupation sites in crystal structure is conducive to the development of low-cost and high-performance layered cathode materials for sodium-ion batteries.
研究领域:
电化学储能
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材料科学
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固态化学
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能源材料
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电池技术
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过渡金属氧化物
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2024
·
IF 3.8
Yu-Zhen Xu,Yu-Le Wang,Yu-Dong Shan,Song-Hai Wu,Yong Liu,Xu Han
Selective oxidation of cyclohexene (Cy) to cyclohexene oxide (Cy-ep) by O2 under solvent- and initiator-free conditions is a challenge in chemical processes, which is still constrained by its low selectivity (theoretical selectivity of 50.0%). Given the low epoxide selectivity (<20.0%) of single metal catalysts, we propose a relay catalysis strategy on the oxidation of Cy to Cy-ep with high selectivity by the spherical Mg–Mo bimetallic oxide (MMO). Such a relay catalyst exhibits a desirable Cy conversion of 31.0% and a high selectivity of 49.3% toward Cy-ep. Meanwhile, the high stability and reusability of MMO also indicate its potential to be used for industrial scale-ups. A series of characterizations and DFT calculations reveal that the negatively charged lattice oxygen in [MgII–O–II] adsorbs allylic H of Cy to weaken the bond energy of the allylic C–H bond and form Cy•, and then Cy• rapidly traps O2 to give CyOO•, which subsequently abstracts H from allylic C–H of another Cy to form 2-cyclohexene-1-hydroperoxide (Cy-OOH) and Cy•, achieving the propagation cycle. On the other hand, the Mo(VI) site in MMO catalyzes the produced Cy-OOH peroxo, which then oxidizes Cy to Cy-ep and 2-cyclohexene-1-ol. This work provides insight into the relay catalyst for the epoxidation of olefin with O2 with high selectivity under solvent- and initiator-free conditions.
研究领域:
化学工程
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材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2024
·
IF 5.7
Xinru Wang,Qiuxu Chen,Daming Yang,Ying Li,Dongxu Yin,Baoxin Ni,Wei Lu,Guiru Sun,Ming Feng
Photo-assisted electrochemical strategy has garnered interest for its ability to diminish the large overpotential of lithium-oxygen batteries (LOBs). Nonetheless, creating a sophisticated photocatalyst capable of absorbing a wide spectrum of light and dramatically lowering the recombination rate for electron-hole pairs presents a significant challenge. Herein, we design an Ag-doped ZnO (Ag@ZnO) hollow nanosphere as photocatalysts to boost the reaction dynamics of photo-assisted LOBs. The Ag@ZnO hollow nanospheres, featuring a mesoporous structure, are beneficial for improving O 2 transport and enabling the retention of discharge products. Additionally, the ability to absorb light and the efficiencies of electron-hole separation are enhanced for Ag@ZnO as a result of Ag doping. The electrons generated by photoexcitation facilitate the conversion of O 2 to produce Li 2 O 2 during discharge, whereas during charging, the presence of holes causes the decomposition of Li 2 O 2 . Consequently, a significantly low overpotential of 0.22 V, ultrahigh cycling efficiency of 93.73%, and good reversibility was achieved for the photo-assisted LOBs using Ag@ZnO. We consider that this work can offer a reliable strategy to improve electrochemical kinetics and contribute to the development of efficient photocatalysts for photo-assisted LOBs.
研究领域:
材料科学
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能源存储与转换
·
光电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Linna Dai,Xin Zhou,Yuan Yang,Pei Hu,Lijie Ci
Nonaqueous Li − O 2 battery (LOB) is considered one of the most promising energy storage system due to its ultrahigh theoretical specific capacity (3500 Wh kg −1 ). Introducing vacancies in CoMn 2 O 4 catalysts is regarded as an effective strategy to enhance the electrochemical performances of LOB. However, the relation between vacancy types in CoMn 2 O 4 and catalytic performances in the LOB remains ambiguous. Herein, ordered porous CoMn 2 O 4 with oxygen and metal vacancies is obtained via solvothermal reaction followed by temperature-controlled calcination using polystyrene spheres as templates. The increase in treatment temperature reduces the content of oxygen vacancies while increasing that of the metal vacancies. Notably, experimental results and theoretical calculations show that oxygen vacancies in CoMn 2 O 4 have a greater influence than metal vacancies in modulating the LiO 2 adsorption during the reaction processes and reducing the overpotential. CoMn 2 O 4 synthesized at 500 ℃ (CoMnO-500) with higher oxygen vacancies exhibits stronger adsorption onto the LiO 2 , facilitating the formation of film-like Li 2 O 2 . Therefore, an LOB with the CoMnO-500 catalyst presents the lowest overpotential of 1.2 V and longest cycle lifespan of 286 cycles at a current density of 200 mA g −1 . This study offers insights into the effect of CoMn 2 O 4 vacancies on the formation pathway of Li 2 O 2 discharge products.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2021
·
IF 10.588
Zhiwei Yang,Yiwen Luo,Jiapeng Yue,Xinyu Wang,Hao Xu,Qian Ye,Yujian Zhang,Xinyi Xing,Qingguo Wang,Jing Zhang
This study proposes a method to activate O 2 by accelerating the corrosion process for zero-valent zinc (ZVZ) with the assistance of Cu(II), promoting the consecutive production of reactive oxygen species . The mechanisms for reactive oxygen species generation are clarified with metronidazole (MTZ) as the targeted pollutant. The outcome suggests the association of Cu(Ⅱ) and ZVZ presents an apparent cooperative activity, an enhancement of 85% in MTZ removal is attained for the ZVZ/Cu(Ⅱ) system after 10 min compared to that for ZVZ. Analysis of the mechanisms involved indicates that this improvement is due to the addition of Cu(Ⅱ), which can accelerate the corrosion of ZVZ. In addition, quenching experiments and electron paramagnetic resonance (EPR) technology show that superoxide radicals (·O 2 − ) result in rapid MTZ degradation. The primary component that is liable for O 2 activation and a certain amount of H 2 O 2 generation is verified to be ZVZ. Moreover, Cu(I) is detected in the ZVZ/Cu(Ⅱ) system, which arises from a direct reduction pathway driven by ZVZ and an indirect reduction pathway driven by active hydrogen atoms .
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）