PROCEEDINGS OF THE COMBUSTION INSTITUTE
·
2020
·Vol. 38
·期 4
·5475-5484
·
IF 5.627
Jianghui Luo,Qianjin Lin,Wenxiang Xia,Yizhuo He,Mei Mei,Lixin Lu,Yang Liu,Chun Zou
Pressurized oxy-fuel combustion has been attracting increasing attentions due to its improved efficiency and low cost. The present study reports ignition delay times (IDTs) of pyridine under O 2 /CO 2 atmospheres within a temperature range from 1202 to 1498 K at pressures from 2.2 to 10 bar for equivalence ratios of 0.5, 1.0, and 2.0. The experimental results were compared with the IDTs of pyridine under O 2 /Ar atmospheres from MacNamara et al.. The comparison results indicate that the IDTs of pyridine under O 2 /CO 2 atmospheres are evident longer than those under O 2 /Ar atmospheres even at low pressure. A modified kinetic model (HUST pyridine Model) was proposed based on our previous mechanism. HUST pyridine Model predicted well the IDTs under both O 2 /CO 2 and O 2 /Ar atmospheres obtained in shock tubes and the species profiles under both O 2 /CO 2 and O 2 /N 2 atmospheres obtained in plug flow reactors . HUST pyridine Model, Alzueta Model, and Pyridine LTO Model were evaluated. The results show that the performance of HUST pyridine Model is much better than Alzueta Model, and Pyridine LTO Model. The main reason is that the net reaction rate of C 5 H 5 N + O = C 5 H 4 N + OH in HUST pyridine Model is much faster than that in Aluzeta Model. The effect of CO 2 on the ignition of pyridine at elevated pressures has been analyzed in detail. The oxidation pathways of pyridine are also analyzed at different pressures.
研究领域:
燃烧化学
·
化学动力学
·
能源工程
·
燃料科学
·
高压物理
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DOI
高影响因子
Nano Research
·
2018
·Vol. 12
·期 3
·517-523
·
IF 7.994
Liu Tie,Wang Leidanyang,Huang Tao,Yu Aishui
Design and fabrication of framework-structured porous precursors have been regarded as a prospective albeit challenging strategy to obtain bimetal/NC-enriched bifunctional elecrocatalysts. In this work, an effective bottom-up approach involving solution-based self-assembly and a post-annealing process was developed to confine (Co, Zn)-N-C active sites into N-enriched graphitic carbon nanocages. This novel architecture containing N-doped-C stabilized bimetallic nanoparticles derived from ZIF precursors was well-studied by a series of characterization and analysis techniques. Details were given that these well-dispersed (Co, Zn) nanoparticles were encapsulated into the pyridinic-N-dominated graphitic carbon nanocage with a total metal loading of approximately 7.4 at.%. This favorable hierarchical structure not only enhances the electron conductivity, but also owns a sufficient BET surface area facilitating the gas-liquid-solid triphase reaction and producing more space to store discharge products. Importantly, results infer that the interesting nanoframes manifests a satisfying ORR/OER activity and enhanced cell performance whether liquid or solid-state electrolytes are used. As such, our work rationalizes that this type of cage-shaped bimetal-N-C material is promising for high-performance Li-O 2 batteries.
研究领域:
材料科学
·
电化学
·
纳米催化
·
能源存储
·
功能材料
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DOI
高影响因子
Journal of Materials Chemistry A
·
2021
·Vol. 10
·期 2
·740-751
·
IF 12.732
Lichong Peng,Yaxin Sun,Shiquan Guo,Congju Li
Oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) involve proton coupled electron transfer reaction (PCET), resulting in sluggish redox kinetics. At present, the development of high-efficiency bifunctional oxygen electrocatalysts is still a puzzling challenge. Herein, we propose a scalable strategy for embedding and beading ZIF-derived hollow Co–Nx nanocube cage dispersion implanted with porous carbonized nanofibers (EH/PCNFs and BH/PCNFs) through electrospinning and annealing. The cobalt species prevent themselves from agglomerating during the annealing process through the “fence” effect of the non-volatile Zn species, thereby synergizing with ligand volatilization to facilitate the formation of Co–Nx nanocube cages. Benefiting from the ultralong interconnected multi-layered carbon nanofiber matrix, the hollow Co–Nx nanocube cages can change the charge density and electron distribution of the carbon nanofiber matrix, endowing the carbonized nanofiber carrier with special surface polarization and accelerating the electrocatalytic kinetics. Remarkably, the integrated Li–O2 batteries (LOBs) based on BH/PCNFs and EH/PCNFs electrodes exhibit significantly decreased charge/discharge polarization (0.79 V) and a long-term cyclability (147 cycles) under a cut off capacity of 500 mA h g−1 at 200 mA g−1. This work might be beneficial for the practically viable design and manufacture of dual-function oxygen electrocatalysts.
研究领域:
材料科学
·
电化学
·
能源存储
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DOI
高影响因子
Science China-Materials
·
2016
·Vol. 59
·期 8
·618-628
·
IF 0
Yi Ting-Feng,Han Xiao,Yang Shuang-Yuan,Zhu Yan-Rong
Layered Li 1.2 Mn 0.56 Ni 0.16 Co 0.08− x
Al
x
O 2 (0 ≤ x ≤ 0.08) cathode materials were successfully synthesized by a sol-gel method. X-ray diffraction and the refinement data indicate that all materials have typical α-NaFeO 2 structure with R -3 m space group, and the a -axis has almost no change, but there is a slight decrease in the c lattice parameter as well as the cell volume. Scanning electron microscopy and high resolution transmission electron microscopy prove that all the samples have uniform particle size of about 200–300 nm and smooth surface. The energy-dispersive X-ray spectroscopy mapping shows that aluminum has been homogeneously doped in the Li 1.2 Mn 0.56 Ni 0.16 Co 0.08 O 2 cathode material. The cyclic voltammetry and electrochemical impedance spectroscopy reveal that appropriate Al-doping contributes to the reversible lithium-ion insertion and extraction, and then reduces the electrochemical polarization and charge transfer resistance. Li 1.2 Mn 0.56 Ni 0.16 Co 0.08− x
Al
x
O 2 ( x = 0.05) shows the lowest charge transfer resistance and the highest lithium-ion diffusion coefficient among all the samples. The Li-rich electrodes with low-level Al doping shows a much higher discharge capacity than the pristine one, especially the Li 1.2 Mn 0.56 Ni 0.16 Co 0.08− x
Al
x
O 2 ( x = 0.05) sample, which exhibits greater rate capacity and better fast charge-discharge performance than the other samples. Li 1.2 Mn 0.56 Ni 0.16 Co 0.08− x
Al
x
O 2 ( x = 0.05) also exhibits higher discharge capacity than the pristine one at each cycle at 55°C. These results clearly indicate that the high rate capacity together with a good high rate cycling performance and high-temperature performance of the low-Co Li 1.2 Mn 0.56 Ni 0.16 Co 0.08− x
Al
x
O 2 ( x =0.05) is a promising alternative to next-generation lithium-ion batteries.
研究领域:
材料科学
·
电化学
·
储能技术
·
锂离子电池
✓ 已验证
DOI
Catalysis Science & Technology
·
2024
·
IF 4.4
Pengken Li,Hui Zhao,Rong Ji,Wenwen Chi,Xinyu Sun,Yuming Dong,Yongfa Zhu
A one-step two-electron oxygen reduction pathway is crucial for the stable and efficient photosynthesis of hydrogen peroxide. However, the lower oxygen adsorption and activation capacity significantly restrict the ability of the one-step two-electron oxygen reduction pathway. In this work, a covalent organic framework containing a diacetylene unit (COF-Tfp-BDDA) as an efficient oxygen reduction active site was designed for the photosynthesis of hydrogen peroxide. This work demonstrates that the introduction of the diacetylene unit efficiently improved the oxygen adsorption and activation capacity of the COF. Additionally, the introduction of a diacetylene unit effectively promoted charge separation. COF-Tfp-BDDA exhibited a superior rate of H2O2 preparation (880 μmol g−1 h−1) under visible light irradiation from pure water and oxygen, better than most COF-based photocatalysts. The catalyst exhibited a stable hydrogen peroxide photosynthesis efficiency above 100 hours in cycling experiments. Based on the experimental and DFT calculation results, the introduction of a diacetylene unit not only enhances the adsorption and activation of oxygen but also alters the reduction pathway of oxygen, leading to effective charge separation. These factors contribute to the efficient photosynthesis of hydrogen peroxide in pure water. This work provides a novel idea regarding the application of COFs in the field of solar energy conversion.
研究领域:
材料科学
·
光催化
·
太阳能转化
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产品关联
DOI
高影响因子
Science Bulletin
·
2018
·
IF 4.136
Zhen-Dong Yang,Zhi-Wen Chang,Qi Zhang,Keke Huang,Xin-Bo Zhang
A facile synthesis of the hierarchically porous cathode with Mo 2 C nanoparticles through the electrospinning technique and heat treatment is proposed. The carbonization temperature of the precursors is the key factor for the formation of Mo 2 C nanoparticles on the carbon nanofibers (MCNFs). Compared with the Mo 2 N nanoparticles embedded into N-doped carbon nanofibers film (MNNFs) and N-doped carbon nanofibers film (NFs), the battery with MCNFs cathode is capable of operation with a high-capacity (10,509 mAh g −1 at 100 mA g −1 ), a much reduced discharge-charge voltage gap , and a long-term life (124 cycles at 200 mA g −1 with a specific capacity limit of 500 mAh g −1 ). These excellent performances are derived from the synergy of the following advantageous factors: (1) the hierarchically self-standing and binder-free structure of MCNFs could ensure the high diffusion flux of Li + and O 2 as well as avoid clogging of the discharge product, bulk Li 2 O 2 ; (2) the well dispersed Mo 2 C nanoparticles not only afford rich active sites, but also facilitate the electronic transfer for catalysis.
研究领域:
材料科学
·
电化学
·
纳米技术
·
能源存储
✓ 已验证
DOI
PubMed
高影响因子
IET Nanobiotechnology
·
2020
·Vol. 14
·期 5
·347-356
·
IF 1.859
Mei Yang,Qingyuan Gui,Jinlei Ma,Lei Qi,Bijun Bao,Yida Huang
In this study, Gd 2 O 2 S:Ln 3+ (Ln 3+ = Yb 3+ , Er 3+ ) upconversion nanotubes (UCNTs) were synthesised by using Gd(OH) 3 :Ln 3+ (Ln 3+ = Yb 3+ , Er 3+ ) nanotubes as the template. The luminescent and biological properties of Gd 2 O 2 S:Ln 3+ (Ln 3+ = Yb 3+ , Er 3+ ) UCNTs, along with photodynamic therapy (PDT) applications of the Gd 2 O 2 S:8%Yb 3+ , 2%Er 3+ UCNT–Ce6 (chlorin e6) nanocomposites, were systematically studied. The resultant UCNTs showed excellent biocompatibility with human retinal pigment cells (ARPE-19) even after a prolonged incubation time of 72 h, and could be used as luminescent probes. Microscopic imaging revealed that the UCNTs existed mainly in cytoplasm. PDT studies on the Gd 2 O 2 S:8%Yb 3+ , 2%Er 3+ UCNT–Ce6 nanocomposites indicate that the growth of the tumour (cell) could be inhibited dramatically when it was injected (incubated) with Gd 2 O 2 S:8%Yb 3+ , 2%Er 3+ UCNT–Ce6 nanocomposites under the irradiation of 980 nm laser.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POWER SOURCES
·
2012
·
IF 4.951
Jing Lin,Daobin Mu,Ying Jin,Borong Wu,Yunfeng Ma,Feng Wu
Li-rich layered composite Li[Li 0.2 Ni 0.2 Mn 0.6 ]O 2 is prepared by a novel approach in which carbon felt acts as a carrier for synthesis reaction . The as-prepared material is characterized by SEM, ICP and XRD , its electrochemical performance is also examined with galvanostatic charge/discharge and CV measurements. It is showed that the facile process controls effectively the particle growth (in size around 100–200 nm) of the composite and its chemical composition . The as-prepared material shows a high initial discharge capacity about 288 mAh g −1 when charged to 4.8 V, and a retained value of 246.8 mAh g −1 in the 40th cycle. The crystalline structure of the composite is simulated further by Material Studio. It is revealed that the composite has a compatible layer structure merged by Li 2 MnO 3 and LiNi 0.5 Mn 0.5 O 2 , which makes substantial contribution to the cycleability of the electrode. In addition, the lithiation/delithiaion properties including charge transfer resistance and lithium ion diffusion coefficient are studied with electrochemical impedance spectra.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2025
·
IF 8.3
Daming Yang,Yingyue Zhang,Jiaqi Sun,Xinyu Zhang,Ze Gao,Qilong Sun,Tong Wu,Wei Lu,Guiru Sun,Ming Feng
The photo-assisted strategy is viewed as a promising method to improve the ORR and OER performance of Li–O 2 batteries. Nevertheless, designing a photocatalyst that ensures wide light absorption and minimizes the recombination of photoinduced electrons and holes is still a notable challenge. In this study, 2D porous Co 3 O 4 nanosheets are synthesized as photocatalysts for photo-assisted Li–O 2 batteries. Their unique structure improves surface area, facilitates O 2 transport, and stores discharge products. Equally, the Co 3 O 4 nanosheets exhibit strong light responsiveness and photocatalytic activity. Upon optical field, photoinduced electrons and holes are successfully separated on Co 3 O 4 nanosheets, which promotes the formation and decomposition of Li 2 O 2 , respectively. Li–O 2 cells using Co 3 O 4 nanosheets display a low overpotential of 0.15 V and good cycling stability under optical field. These findings highlight the potential of Co 3 O 4 nanosheets as photocatalysts for photo-assisted Li–O 2 batteries, providing a foundation for future energy storage advancements.
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
ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Qiuli Wang,Jiahao Meng,Lingling Huang,Feng Wu,Xue Yi,Guanghao Su,Ying Li,Zhenqing Hou,Zhongxiong Fan
How to efficiently synthesize toxic chemo-drugs in the hypoxia tumor microenvironment still faces a huge challenge. Herein, we have tailored engineered vehicle-free nanoreactors by coordination-driven co-assembly of photosensitizer indocyanine green (ICG), transition metal platinum (Pt), and nontoxic 1,5-dihydroxynaphthalene (DHN) to self-amplify O2 and cascade chemo-drug synthesis in tumor cells for self-reinforcing hypoxic oncotherapy. Once vehicle-free nanoreactors are internalized into tumor cells, they show a serious instability that results in rapid disassembly and on-demand drug release under the stimuli of acidic lysosome and laser radiation. Notably, the released Pt can efficiently decompose the endogenous hydrogen peroxide (H2O2) into O2 to alleviate tumor hypoxia, which is conducive to enhancing the photodynamic therapy (PDT) efficiency of the released ICG. Complementarily, a large amount of the 1O2 generated by PDT can efficiently oxidize the released nontoxic DHN into the highly toxic chemo-drug juglone. Therefore, such vehicle-free nanoreactors can achieve intracellular on-demand cascade chemo-drug synthesis and self-reinforce photo-chemotherapeutic efficacy on the hypoxic tumor. On the whole, such a simple, flexible, efficient, and nontoxic therapeutic strategy will broaden the study of on-demand chemo-drug synthesis and hypoxic oncotherapy.
研究领域:
癌症治疗
·
纳米医学
·
生物化学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Bin He,Huanhuan Liu,Zheng Lin,Lei Yan,Jiqiang Ning,Yijun Zhong,Changcheng Zheng,Ziyang Zhang,Yong Hu
The practical application of photocatalytic water splitting is essentially limited by the slow kinetic nature of the water oxidation process. Therefore, it is highly desirable but challenging to explore a low-cost and high-efficiency water oxidation catalyst for the aim of commercialization and industrialization. We herein report the first-time synthesis of a novel and high-efficiency visible-light-driven photocatalyst composed of flower-like Co(CO 3 ) 0.5 (OH)·0.11H 2 O (CCO) nanowires and Bi 2 WO 6 (BWO) nanosheets, i.e. CCO/BWO nanocomposite, via a facile hydrothermal method. Without utilizing any additional cocatalyst, the composite of CCO/BWO in 30% weight ratio exhibits extraordinarily high photoactivity and photostability towards O 2 evolution, achieving an average O 2 generation rate of 953 µmol h −1 g −1 under visible-light irradiation (λ > 420 nm).
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2021
·Vol. 9
·期 42
·24056-24063
·
IF 12.732
Yanfang Chen,Xuemei Yan,Jixiang Xu,Lei Wang
H2O2 has a wide range of uses as an oxidant and is also utilized as a high density and environmentally friendly fuel. In this study, crystalline g-C3N4 was modified with K+, Ni and N-doped carbon by thermal-polymerization of Ni2+-anchored and polyvinyl pyrrolidone-encapsulated melamine-cyanuric acid supramolecules, followed by re-calcination in a KCl–LiCl mixture. The obtained strip-like g-C3N4 nanocrystals exhibited high charge separation efficiency and good light absorption capability. Density-functional theory calculations confirmed that the orbital hybridization of Ni–N atoms enabled the formation of charge-transfer channels, which can capture electrons, achieve enhanced oxygen adsorption and reduction via a two-electron pathway. Under the synergistic effects of K+, Ni and N-doped carbon dopants and crystallinity, the obtained sample exhibited high photocatalytic H2O2 yields of 79.6 μM in O2-saturated pure water, which was 10-fold higher than the yield using pristine g-C3N4. This work provides a novel design for production of highly efficient photocatalysts for H2O2 production.
研究领域:
材料科学
·
环境科学
·
化学
✓ 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）