PROCEEDINGS OF THE COMBUSTION INSTITUTE
·
2024
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IF 5.3
Nan Liu,Qi Chen,Xianwu Jiang,Jie Chen,Lidong Zhang,Jiaying Pan,Haiqiao Wei,Xingqian Mao
This work presents a three-stage hybrid nanosecond discharge (NSD) and direct current (DC) discharge assisted n -C 5 H 12 /O 2 /N 2 ignition with lower discharge energy and higher energy efficiency. The reaction rate coefficients between O 2 (a 1 Δ g ) and n -C 5 H 12 are updated by mass/Master equation simulation. The promotive ignition enhancement via reaction channel O 2 (a 1 Δ g ) + n -C 5 H 12 → C 5 H 10 + H 2 O 2 in the hybrid NSD/DC discharge is demonstrated. The results show that the ignition delay time of the three-stage hybrid plasma assisted ignition is 1–2 orders of magnitude shorter than that of the two-stage hybrid discharge when the reduced electric field strength in the DC discharge stage is over 10 Td. Meanwhile, the plasma-enhanced energy efficiency of three-stage hybrid discharge increases. This improved efficiency on ignition enhancement is due to the kinetic enhancement by the electronically excited species and radicals (O 2 (a 1 Δ g ), O( 1 D), N 2 (B) and O). The kinetic and thermal effects by plasma are effectively intergated to enhance ignition. However, more discharge energy deposited in the vibrationally excited states N 2 ( v ) in the two-stage hybrid discharge is less efficient on ignition enhancement due to the thermal contribution via vibrational-translational relaxation. In the aspect of NO x /N 2 O emissions, reduction efficiency of the three-stage hybrid discharge is two times higher than that of the two-stage hybrid discharge. By controlling the N/N( 2 D) production pathway e + N 2 → e + N + N( 2 D), the three-stage hybrid discharge reduces NO x and N 2 O production by 61.1 % and 90 %, respectively. The results show that the ignition delay time is non-monotonically dependent on the discharge pulse number. There exist optimal pulse number, reduced electric field and effective threshold power density of DC discharge to achieve maximum ignition enhancement and low NO x /N 2 O emissions. This study provides valuable insights into the use of NSD/DC hybrid discharge technology in advanced engines to achieve energy-efficient ignition enhancement and reduce NO x /N 2 O emissions.
研究领域:
能源科学
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环境科学
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化学动力学
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产品关联
DOI
高影响因子
CATALYSIS TODAY
·
2024
·
IF 5.2
Jipeng Wang,Xinli Tong,Chen Guo,Yahui Wei
The high entropy oxides are widely studied as the potential catalytic materials owing to their unique structure and excellent properties. In this work, a new high entropy oxide catalyst MnFeCoNiCuO x was successfully prepared and used for the oxidative condensation reaction of furfural (FUR) and aliphatic alcohol , where the carbon-chain length can be selectively increased under the mild conditions. For the selective oxidative transformation of FUR with n-butanol, a more than 99.0 % conversion of FUR and 91.5 % selectivity of 2-(furanyl-2-methylene) butanal was obtained at 80 ºC for 2 h. In addition, the oxidative condensation of FUR with ethanol, n-propanol, n-pentanol, n-hexanol and n-heptanol was also carried out with the MnFeCoNiCuO x - LiOH as catalyst system in the presence of molecular oxygen , where a moderate to high product yields were acquired. Furthermore, the characterizations of catalyst showed that the existence of abundant oxygen vacancy and high specific area was greatly important to the catalytic reactions .
研究领域:
化学工程
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催化科学
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
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IF 6.3
Yajuan Jiang,Shining Zhang,Chunyu Xu,Bin Jia,Shijie Ren,Wenyu Zheng,Yicong Huang,Kunpeng Jiang,Xiuyun Zhang,Yunyun Zhao,Guisheng Zhu,Huarui Xu
In this paper, biomass carbon@Li(Ni 0.6 Co 0.4 )O 2 (BC@LNCO) micron-tube is successfully synthesized via a bio-templating method as cathodic material for lithium-ion hybrid supercapacitors. Cobalt nickel subcarbonates nanowires arrays are homogeneously grown on bagasse substrate via a unique synthesis strategy using a toluene-water interface reaction process, which subsequently transform as BC@LNCO micron-tube after lithiation process. The distinctive biomass fibre structure of bagasse biomass carbon leads to a significant enhancement in active sites in the BC@LNCO composite, which facilitates lithium-ion diffusion and enhances the contact area between the electrode and electrolyte. So, the prepared BC@LNCO electrode demonstrates improved electrical performances with a high specific capacitance of 921 F g −1 at 1 A g −1 and a good rate performance with 72 % retention at 10 A g −1 . In addition, the lithium-ion hybrid supercapacitor is fabricated with BC@LNCO and activated carbon (AC) as positive and negative electrodes, respectively. The BC@LNCO//AC device demonstrates a good energy density of 56.25 Wh kg −1 at 818.4 W kg −1 , and maintains 25.06 Wh kg −1 when the power density is up to 8143.42 W kg −1 , indicating that the prepared BC@LNCO composite can be a promising candidate as electrode material for Li-ion hybrid supercapacitor.
研究领域:
材料科学
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能源存储
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产品关联
DOI
高影响因子
Chemical Science
·
2024
·
IF 7.6
Yinglei Tao,Tao Wang,Xingyu Yu,Ke Gong,Hao Gong,Haixia Chen,Xiaoli Fan,Aidi Zhang,Xianli Huang,Kun Chang,Jianping He
Li–O2 batteries (LOBs) boast an exceptionally high theoretical energy density; however, the slow kinetics of the oxygen electrode reaction have been a significant hurdle in their advancement and practical application. In this study, a composite of bismuth oxyhalide heterojunction incorporated with metal–organic frameworks (MOFs) was engineered on carbon cloth (Zr-MOF/BiOIBr/CC) as an efficient bifunctional catalyst to enhance the oxygen electrode reaction in photo-assisted LOBs. Compared to Zr-MOF/CC, Zr-MOF/BiOIBr/CC significantly expands the light absorption spectrum of the catalyst. Furthermore, the built-in electric field in the heterojunction aids in the separation and directional movement of photogenerated carriers, thereby expediting the reaction kinetics of LOBs. Consequently, the photo-assisted LOBs with Zr-MOF/BiOIBr/CC as the cathodes display a discharge potential of 3.05 V, a low charge potential of 3.20 V, and an energy efficiency of up to 95.3%, and can sustain an extended cycle life of over 255 cycles. This study underscores the potential application of MOFs/semiconductor heterostructural materials in photo-assisted LOBs and offers insights into the systematic design of photo-assisted air batteries and other advanced semiconductors.
研究领域:
材料科学
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电化学
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能源存储
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产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2024
·
IF 5.3
Xiang Yu,Yuwei Mi,Zihan Gong,Yongfang Zhang,Lei Wang,Suyuan Zeng
Constructing heterojunctions is an effective strategy for increasing semiconductor photocatalytic activity. Herein, a Bi2O3/Bi4O5Br2 type-II heterojunction was synthesized using a simple one-pot solvothermal route. The 0-dimensional (0D) Bi2O3 nanoparticles are uniformly distributed within the 2D Bi4O5Br2 nanosheets with (101̅) facets dominantly exposed. In comparison with pure Bi2O3 and Bi4O5Br2, they show higher photocatalytic activity degradation of resorcinol (RO) and Rhodamine B (RhB). The Bi2O3/Bi4O5Br2 composite containing 10% Bi2O3 (BOB4) displays the best photocatalytic activity. For instance, compared with pure Bi4O5Br2 and Bi2O3, the k(RO) values of BOB4 (0.58 h–1) are 3.1 and 4.8 times higher. The enhanced photocatalytic activity is attributed to the formation of a large heterojunction interface that results from the homogeneous distribution of Bi2O3 nanoparticles in the Bi4O5Br2 nanosheet, which effectively enhances the photogenerated charge separation in a type-II mode. Major active species include superoxide radicals (•O2–), hydroxyl radicals (•OH), and holes (h+). In addition, the Bi2O3/Bi4O5Br2 photocatalysts exhibit outstanding resistance to inorganic ions, pH, water matrix, as well as outdoor sunlight and favorable stability and biocompatibility. This work presents a simple method to construct Bi-based heterojunction architectures for photoactivity improvement.
研究领域:
材料科学
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环境科学
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化学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
·
IF 13.3
Wei Du,Zhihua Zhang,Jundi Wang,Nan Song,Xuezhi Duan,Xinggui Zhou
Propylene epoxidation by H 2 and O 2 to propylene oxide (HOPO), as a novel method for PO production, has attracted widespread attention due to its economic and environmental advantages. Acrolein is a notable byproduct arising in HOPO reaction over Au/TS-1 catalyst, and is traditionally thought to be exclusively formed on Au site through propylene oxidation. However, on the intraporous and external surface Au sites of Au-Ti catalysts, the HOPO reaction have been shown to proceed by different mechanisms, yet the effect of active sites distribution on acrolein formation is far from being understood. Herein, we found that the reaction orders in acrolein formation on Au/TS-1 catalyst (H 2 , 0.19; O 2 , 0.44; C 3 H 6 , 0.44) relative to Au/TS-1 with blocked pores (Au/TS-1-B) catalyst (H 2 , −0.36; O 2 , 0.61; C 3 H 6 , 0.52) were quite different, suggesting a variation in the reaction pathway on the catalysts with different Au locations. Moreover, it is found that PO can be converted to acrolein by O 2 on TS-1 zeolite, which is absent on TS-1-B zeolite without micropores. Consequently, acrolein formation on Au/TS-1 catalyst can proceed through two parallel pathways: propylene hydro-oxidation on Au site, and PO conversion by O 2 inside micropores. Furthermore, by designing and preparing the Au/TS-1 catalysts with different structures, the Au locations are closely related to acrolein formation mechanism and kinetic behaviors. This work provides kinetic insights into the acrolein formation pathways in the HOPO reaction on Au/TS-1 catalyst, and is helpful to the rational design and preparation of efficient catalysts with high selectivity.
研究领域:
催化化学
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材料科学
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环境化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2021
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IF 6.707
Shan Jiang,Jing Cao,Minna Guo,Dongdong Cao,Xuemei Jia,Haili Lin,Shifu Chen
Elemental red phosphorus (RP) has an ultra-low activity of splitting water for H 2 and O 2 evolution. In this study, RP was decorated by trace amount of WO 3 to greatly enhance the photocarriers separation and photocatalytic activity for overall water splitting under visible light. The 2.5% WO 3 /RP composite achieved the highest activity to produce H 2 and O 2 , and the activity was 7.0 times that of pure RP under visible light (λ ≥ 420 nm). The significantly increased photocarriers separation of WO 3 /RP was ensured by transient photocurrent, electrochemical impendence, photoluminescence, and time-resolved photoluminescence characterizations. More importantly, WO 3 /RP maintained high stability when it was persistently used for 20 cycles. Based on the reactive oxygen species ( O 2 − and OH) detected during the photocatalytic process, an S-scheme mechanism was proposed for WO 3 /RP composites to efficiently separate the photocarriers. This work provides a notion for improving the overall water splitting activity of RP via an S-scheme photocarriers separation mode.
研究领域:
材料科学
·
环境科学
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DOI
高影响因子
Materials Today Energy
·
2022
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IF 9.257
Jingjun Zhai,Haocheng Ji,Wenhai Ji,Rui Wang,Zhongyuan Huang,Tingting Yang,Chaoqi Wang,Taolve Zhang,Ziwei Chen,Wenguang Zhao,Akhil Tayal,Lei Jin,Jun Wang,Yinguo Xiao
Layered transition metal oxides have been broadly studied due to their great potential in application as cathodes for sodium-ion batteries. However, many single-phase layered transition metal oxides, especially those crystallized in P2- or O3-type structure, possess their individual characteristics incurring unsatisfactory overall performances with respect to the reversible capacity, rate capability, and cycling stability. Here, an effective strategy of constructing the P2/O3 biphasic structure is realized in layered cathode Na 0.7 Ni 0.4 Mn 0.4 Ti 0.2 O 2 through Ti substitution. Through high-resolution scanning transmission electron microscopy and X-ray diffraction, the formation of P2/O3 intergrowth structure was clarified and the proportion of the two phases was determined. Benefitting from the presence of intergrowth structure, the layered cathode provides a competitive rate capability of 100 mAh/g at a high rate of 5 C as well as a prominent cycling stability of 80.04% capacity retention after 300 cycles at 5 C. The improved performance is closely related to the highly reversible phase transition process from P2/O3 to OP4/P3 with less strain and enhanced Na + kinetics. These findings evidence that exploring novel multiphase cathodes is an effective approach to improve the electrochemical performances of cathode for sodium-ion batteries.
研究领域:
材料科学
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电化学
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DOI
高影响因子
ACS Applied Energy Materials
·
2020
·
IF 4.473
Jia Liu,Ying Wang,Dan Zhou,Dan Li,Ziye Kang,Haiming Xie
Although a redox mediator (RM) strategy can lower the overpotential of Li–O2 batteries (LOBs), the redox shuttling results in an undesired RM consumption and a continued decomposition of lithium metal anode, leading to a poor cycling stability. In this work, a hybrid inorganic–organic composite separator based on polyethylene oxide/TiO2/polypropylene (PEO/TiO2/PE) in LOBs has been reported for the first time, which aims to suppress the RM shuttling. The influences of TiO2 nanoparticles and PEO on battery performance are systematically investigated. Benefiting from the synergistic advantages, a LOB with PEO/TiO2/PE separator displays stable cyclability, considerable rate performance, and good reversibility. Additionally, the mechanism of inhibiting shuttling effect by this composite separator is proposed. We hope that this work can give an insight into the development of multiple functional separators for Li anode protection in LOBs.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2020
·
IF 7.632
Zhengyi Qian,Xudong Li,Liguang Wang,Tianpin Wu,Baoyu Sun,Lei Du,Yulin Ma,Chunyu Du,Pengjian Zuo,Geping Yin
Rechargeable aprotic Li–O2 batteries have drawn much attention in light of their ultrahigh theoretical energy density. However, the sluggish kinetics of oxygen cathode reactions lead to huge energy loss, while the unfavorable side reactions associated with the widely used carbon and binder account for fast battery decay during cycles. Herein, hierarchically holey IrNi alloy nanosheets are facilely designed on Ni foam substrate as a freestanding, binder- and carbon-free cathode to address these challenges. The IrNi nanosheets consist of numerous interconnected nanoparticles, forming abundant nanoholes, benefiting active-site exposure. Moreover, the meso-/macropores pave channels for the transfer of oxygen and lithium ions and provide enough accommodation for the insoluble Li2O2 product. The corresponding Li–O2 batteries demonstrate low polarization and excellent cycle stability with full discharge/charge capability (up to 292 cycles at a current density of 0.2 mA cm–2 within a voltage range from 2.3 to 4.3 V). The long-term cycling performance is principally attributed to the exclusive catalytic stability of the holey IrNi nanosheets and its good compatibility with dimethyl sulfoxide-based electrolyte. Our research provides novel insights into the design of robust and freestanding porous cathodes for high energy density Li–O2 batteries.
研究领域:
材料科学
·
电化学
·
能源存储技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2020
·Vol. 8
·期 19
·9813-9824
·
IF 11.301
Yue Li,Jian Song,Mengting Jiang,Mbage Bawa,Xiaohong Wang,Yuyang Tian,Guangshan Zhu
Na5[IMo6O24]·3H2O and a porous aromatic framework (iPAF-1) were used to build an off-the-shelf building material (IMo6@iPAF-1) to realize the highly efficient oxidation of organic sulfurs like oxygenase. The synergy between IMo6 and iPAF-1 resulted in a higher BET surface area, hydrophobic microenvironment, and redox sites to show higher activity in aerobic oxidative desulfurization with almost 100% removal of model organic sulfurs under atmospheric pressure with almost 246 times higher TOFs compared to IMo6. It also showed efficiency in the desulfurization of gasoline and diesel to give very low S contents of 7.1 and 7.6 ppm with 99.3% and 99.4% removal, respectively, at 100 °C for 6 h. More importantly, IMo6@iPAF-1 could also catalyze desulfurization using concentrated O2 mixed with N2 or air instead of pure O2 with better safety and economics, while as low as 4.9 and 6.9 ppm S contents were achieved for gasoline and diesel, respectively. The special surroundings of IMo6@iPAF-1 repelled the sulfone product and allowed it to perform with the same efficiency when recycled without any treatment of the used catalyst.
研究领域:
化学
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环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2020
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IF 9.038
Yong Liu,Ni Tan,Jinrui Guo,Jianlong Wang
In this study, a novel Al°-CNTs-Cu 2 O composite, capable of activating O 2 to generate H 2 O 2 and further to reactive oxygen species (ROSs) at a wide pH range, was synthetized, characterized and applied for the degradation of sulfamerazine. In the activation of O 2 by Al°-CNTs-Cu 2 O composite, H 2 O 2 was generated from the reaction of O 2 with Al°-CNTs, which could be catalytically decomposed into O 2 − and OH by Cu 2 O, the formed Cu(II) could be rapidly reduced to Cu 2 O by Al°-CNTs in composite, which made Al°-CNTs-Cu 2 O composite reusable and decreased the leaching of copper ions into solution. The removal efficiency of SMR and TOC was 73.91 % and 56.80 %, respectively at initial pH = 5.8, T = 20 °C, O 2 flow rate = 100 mL/min, Al°-CNTs-Cu 2 O dosage = 2 g/L, SMR = 50 mg/L, and reaction time = 60 min. The removal efficiency of SMR kept almost unchanged and the concentration of copper ions in solution was below 0.5 mg/L. The Al°-CNTs-Cu 2 O/O 2 process could be used as a novel catalyst for the degradation of refractory organic contaminants in water and wastewater by Fenton-like process at a wide pH range through the in situ generation of H 2 O 2 .
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子