INTERNATIONAL JOURNAL OF ENERGY RESEARCH
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2021
·Vol. 46
·期 1
·370-382
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IF 5.164
Yuzhe Liu,Hao Wang,Chengcai Li,Shaohui Wang,Lin Li,Chengwen Song,Tonghua Wang
Summary The development of electric vehicles is increasing the demand for supercapacitors, for which carbon materials can make excellent electrodes. In this study, waste scraps of polyimide (PI) film were used to fabricate several flaky porous carbon materials for use as supercapacitor electrodes. The pore structure and functional groups of the porous carbons were tailored by KOH activation. The relationships between pore structure, the carbon matrix, functional groups, and electrochemical performance were investigated via N 2 adsorption, XRD, Raman spectroscopy, FT-IR, XPS, and electrochemical measurements. The flaky porous carbon materials have a graded distribution of hierarchical pore structures and are rich in O/N functional groups. They have an outstanding capacitance retention rate and a high specific capacitance of 482 F g −1 , which is higher than those of PI film-based porous carbons prepared by physical activation and of commercial activated carbon electrodes. Their flaky structure endows them with lower impedance than commercial AC. The materials were used to fabricate electrodes for symmetrical supercapacitors, which displayed high energy densities and excellent cycling stability. This work provides an environmentally benign strategy for the re-use of waste PI film.
研究领域:
材料科学
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环境科学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2021
·Vol. 45
·期 14
·20186-20198
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IF 5.164
Sheng-xue Yan,Shao-hua Luo,Mei-zhu Sun,Qing Wang,Ya-hui Zhang,Xin Liu
Summary The urchin-like NiCo 2 O 4 material was prepared by a one-step hydrothermal method. The optimal synthetic conditions were systematically investigated by an orthogonal test method and single factor of hydrothermal time to evaluate the influence of sample morphology and electrochemical performance. The synthesis conditions for preparing NiCo 2 O 4 with different morphologies were systematically studied. In the single factor experiment, when the hydrothermal time is 6, 12, 16, and 24 hours, the corresponding morphologies are urchin-like (NCO-U), flower-like (NCO-F), sheet-like (NCO-S), and block-like (NCO-B), respectively. The element content of the prepared materials under different synthesis conditions was tested by an inductive-coupled plasma emission spectrometer, and an interesting phenomenon was found. As the reaction time increases, the content of Ni + gradually decreases and the content of Co + gradually increases, which may be one of the factors that affect the morphology and electrochemical performance of the material. The specific capacitances of NCO-U, NCO-F, NCO-S, and NCO-B are calculated to be 914.3, 392.2, 313.3, and 277.4 F g −1 , respectively, at a current density of 1 A g −1 . Benefiting from the large specific surface area and rich oxygen vacancy, the as-fabricated urchin-like NiCo 2 O 4 as electrode materials for supercapacitor demonstrates its promising application potential for supercapacitors.
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
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2021
·Vol. 45
·期 15
·21476-21486
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IF 5.164
Yuanlu Xu,Haichao Mu,Xiaoshi Han,Tianjun Sun,Xinfei Fan,Bowen Lv,Zonglin Pan,Yongxin Song,Chengwen Song
Summary Solar interfacial water evaporation is considered as a potential green technology to solve the global shortage of freshwater resources. However, it is still an arduous task to develop a low-cost and efficient solar evaporator with a simple preparation method. Herein, a simple, flexible, and porous polypyrrole-wax gourd (PPy-wax gourd) biomass evaporator was reported for solar evaporation enhancement. Wax gourd had the advantages such as superhydrophilic wettability, massive microporous channels, and easy planting. PPy was a kind of black polymer with excellent light absorption ability, which greatly improved the light absorption of the PPy-wax gourd evaporator within a full spectrum of solar irradiance (300-2500 nm). The PPy-wax gourd evaporator prepared by the perfect combination of wax gourd and polypyrrole realized a superior vapor generation ability (1.57 kg m −2 hours −1 ) with a photothermal conversion efficiency of 77.3% under 1 solar intensity, which was better than some other biomass evaporators developed so far. In addition, the PPy-wax gourd evaporator also exhibited remarkable stability and durability under long-term recycling utilization and harsh environments. Importantly, the PPy-wax gourd evaporator demonstrated prominent wastewater purification capacity and desalination performance for dye wastewater and simulated seawater treatment. Based on these results, this work would offer a new strategy for developing novel biomass thermal evaporators the clean water production.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2020
·Vol. 45
·期 2
·2058-2069
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IF 3.741
Junkai Gao,Xi Tang,Yan Chen,Yi Liu
Summary The thermal conductivity of shape-stabilized phase change material of polyethylene glycols/porous carbon microspheresdoping withcopper particles (PEG/CARM-Cu) was enhanced based on the adsorption and in situ reduction of Cu 2+ using polydopamine microsphere (PDAM)material as the adsorbent. The synthesis of PDAM has the merits of simplicity and environmental friendliness, and the in situ reduction of Cu 2+ through pyrolysis has the advantages of easy operation and cost effectiveness. Copper particles prepared by in situ reduction were tightly fixed on the surface of the support ofporous carbon microsphere (CARM), which avoided the sedimentation of copper particles during the phase change process of PEG/CARM-Cu. According to the SEM, TEM, XRD, TGA and DSC test results, PEG/CARM-Cu possessed favorable thermal reliability and stability, and the phase change enthalpy of PEG/CARM-Cu-2 could reach 101.50 J/g. Additionally, the thermal conductivity of PEG/CARM-Cu-2 (0.497 W/(m·K)) was enhanced by 93.3% compared to that ofpure PEG (0.257 W/(m·K)). Therefore, the PEG/CARM-Cu developed in this paper possessed great potential for real applications.
研究领域:
材料科学
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能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
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2020
·Vol. 45
·期 2
·2899-2911
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IF 3.741
Guorong Wang,Zhiliang Jin,Tiansheng Zhao
Summary In this study, a series of nickel/vanadium composites were acquired via a simple in situ growth strategy with the sodium chloride as a regulator. The phase, component, and electrochemical energy storage behavior of the as-prepared electrodes were investigated. Thanks to the addition of sodium chloride for the accession of oxygen vacancy, the prepared composite electrodes show excellent supercapacitor behavior. The resultant NVC-1.8Ov electrode demonstrates a impressive specific capacitance of 9.41 F cm −2 at a current of 10 mA cm −2 , which is about 1.5 times than the NVC electrode. After 5000 charge-discharge cycles under a current of 40 mA cm −2 , the retained 75.7% of its initial capacitance indicate a good cyclic stability. In addition, the NVC-1.8Ov and activated carbon (AC) was used to assemble NVC-1.8Ov//AC asymmetric supercapacitor, which deliver a maximum energy density of 0.471 mWh cm −2 at a power density of 9.319 mW cm −2 . This work provides a new and simple strategy for the preparation of high specific capacitance of asymmetric supercapacitor positive electrode.
研究领域:
材料科学
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电化学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
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2020
·Vol. 45
·期 2
·3305-3314
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IF 3.741
Zhong Ma,Shuai Zhang,Yonggang Lu
Summary NiFe 2 O 4 presents high redox activity and good promoted application prospect in chemical looping processes. However, phase segregation caused by outward diffusion of Fe cations often lead to low cycling stability for NiFe 2 O 4 . In this study, the inherent mechanism of phase segregation for NiFe 2 O 4 was investigated deeply. The results indicated that reduction degree exhibited significant influence on the phase segregation of NiFe 2 O 4 in successive redox cycles. When NiFe 2 O 4 was reduced to Ni and Fe 3 O 4 in redox cycles, NiFe 2 O 4 displayed stable redox activity without phase segregation. As the reduction degree reached to FeO and FeNi, a needle-like structure with Fe enrichment was formed on the surface of the first cycled NiFe 2 O 4 . In the subsequent redox cycles with deep reduction degree, both severe phase segregation and deactivation were occurred for spent NiFe 2 O 4 sample. It can be seen that phase segregation is the main reason for the deactivation of NiFe 2 O 4 instead of surface sintering in redox cycles. The results of this work provide guidance for the development of NiFe 2 O 4 -based oxygen carriers with high redox performance.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
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2020
·Vol. 44
·期 13
·10295-10306
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IF 3.741
Huijia Huang,Changjiang Zhao,Fei Ding,Huan Li,Shuoqing Zhang,Xingjiang Liu,Qiang Xu
Summary Lithium-sulfur (Li-S) batteries have a great potential for the future development of energy industry. However, the high-temperature performance of Li-S batteries is still facing great challenge due to the high flammability of the electrolyte, sulfur cathode as well as the separator. The separator modification is an effective method to improve the thermal stability of separator and the electrochemical performance of Li-S batteries under elevated temperatures. However, the reported methods of separator coating are too complicated to be applied in the industrial production. Here, a novel thermo-stable composite separator (M-Celgard-p), in which a layer of silicon dioxide-poly (propylene carbonate) based electrolyte (nano-SiO 2 @PPC) with a high ionic-conductivity of 1.03 × 10 −4 S cm −1 is coated on the commercial Celgard-p separator, is prepared by using a simple dipping method. Compared to the Li-S battery assembled with Celgard-p separator, the M-Celgard-p separator combined with a sulfur/polyacrylonitrile (S/PAN) cathode can improve the electrochemical performance of Li-S batteries, especially their high-temperature stability. As a result, the (S/PAN)/M-Celgard-p/Li cell delivers a high specific capacity of 724.7 mAh g −1 at 1.0 A g −1 after 200 cycles and presents a good rate capability of 1408 mAh g −1 at 1.0 A g −1 and 1216 mAh g −1 at 2.0 A g −1 . More importantly, the (S/PAN)/M-Celgard-p/Li cell can exhibit a capacity retention ratio of 69.4% after 200 cycles at 60°C. The M-Celgard-p separator with high Li-ion conductivity can not only block the “shuttle-effect” of polysulfides during cycling but also enhance the thermal stability under elevated temperatures. This work presents a simple dipping method to prepare composite separator with excellent thermal stability, which enhance the rate performance and cyclic stability of Li-S batteries under elevated temperatures. We believe this work can provide a new way to develop more reliable Li-S batteries for practical applications.
研究领域:
材料科学
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电化学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2019
·Vol. 43
·期 14
·8439-8446
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IF 3.343
ZhiZhong Xie,Caiyun Xu,Lina Zhou,Dan Liu,Chenyang Chen,Haolin Tang,Junsheng Li,Xi Li,Deyu Qu
Summary A hydrogen ion supercapacitor cell was constructed with an electrochemical double-layer carbon material as positive electrode and an electrochemical hydrogen storage composite material as negative electrode. The electrochemical performances of both electrodes and hybrid device were investigated by varying of the mass ratio of positive and negative electrode. It was found to be that both electrodes went through the different hydrogen ion storage processes and the capacity of this hybrid supercapacitor was highly correlated with the negative to the positive electrode ratio. The highest capacity was achieved at ratio of 1:7; further increasing of this ratio may downgrade the performance of the hybrid system. With this optimized ratio, the hybrid device demonstrated good electrochemical performance. Novelty Statement A new hybrid supercapacitor is developed using an electrochemical hydrogen storage cobalt/carbon composite material as negative electrode and a double-layer porous carbon material as positive electrode. In this device, the charge carrier is hydrogen ions generated through the electrolysis of the aqueous electrolyte and, like lithium ion supercapacitor, the H ions rock-chaired between positive and negative electrode during the operation. The structure of this new device is engineered, and the energy storage and conversion mechanisms on both electrodes during the operation are also discussed.
研究领域:
能源材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
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2020
·Vol. 45
·期 4
·6227-6238
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IF 3.741
Xiangxiang Du,Xuejun Shi,Yanling Li,Kesheng Cao
Summary Herein, N, S-co-doped graphene hydrogel (N/SGH) was first prepared by one-pot feasible hydrothermal approach using thiourea as a dopant for both N and S sources. And then, polyaniline (PANI) was grown on the surface of N, S-co-doped graphene hydrogel via simple adsorption of aniline monomer and in situ polymerization process. The N, S-co-doped graphene/polyaniline (N/SGH/PANI) composite hydrogel was fabricated as a free-standing and binder-free electrode material. Due to the co-doped synergistic effect, the N/SGH electrode exhibited enhanced electrochemical performances. The N/SGH electrode displays a specific capacitance of 130.4 F/g at 0.5 A/g. Compared with pure graphene hydrogel (GH), the specific capacitance of N/SGH and N-doped graphene (NGH) electrodes at 0.5 A/g increased by 53% and 20%, respectively. PANI pseudocapacitor material was introduced to further improve its capacitive performance. The resultant N/SGH/PANI composite electrode could achieve a max specific capacitance of 236.5 F/g at 0.5 A/g. In addition, N/SGH/PANI composite electrode showed stable cycle performance with the capacity retention of 95.1% after 1000 cycles performed at 10 A/g. Those provide a fabrication strategy for the design of high-performance supercapacitors electrode materials.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2020
·Vol. 45
·期 4
·6273-6284
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IF 3.741
Xiaolin Shao,Qi Zhang,Xurui Zhang,Jin Yi,Yuyu Liu,Jiujun Zhang
Summary A facile method is developed to fabricate nanoporous, structured, Sn-based catalyst electrodes. Sn, Zn, and multiwalled carbon nanotubes (MWCNTs) are co-electrodeposited on a copper substrate, followed by chemical dezincification in NaOH aqueous solution to remove Zn. By controlling variables such as the contents of Zn and MWCNTs, a series of Sn-MWCNT/Cu (S Z MC) electrodes are fabricated. Experimental results show that using such novel S Z MC electrodes can achieve a HCOO − Faradaic efficiency of over 91% at −0.99 V versus RHE for 10 hours in CO 2 -saturated 0.5 M KHCO 3 aqueous solution. The high performance is attributed to the addition of MWCNTs and Zn, followed by chemical dezincification to remove Zn and then create vacancies in the catalyst structure, which results in a special porous structure of S Z MC with large surface area. Then ECSA is used for enhancing the catalytic activity and selectivity of HCOO − production, as well as promoting intermediate adsorption and mass transfer.
研究领域:
材料科学
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电化学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2020
·Vol. 45
·期 5
·7120-7128
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IF 3.741
Menglu He,Jia Jia,Qing Sun,Weixin Zhang
SUMMARY Li-O 2 battery has attracted much attention due to its ultra-high theoretical energy density in the field of electrochemical energy storage. The introduction of efficient electrocatalyst can effectively accelerate the reaction rate of ORR and OER, so as to improve the coulomb efficiency and poor cycle stability of Li-O 2 battery. In this work, a novel hollow N-doped carbon sphere is prepared by using MOF and polystyrene as template, and act as highly efficient oxygen electrocatalyst for rechargeable Li-O 2 batteries. The hollow structure can provide enough oxygen diffusion channel, deposition and decomposition space for reduction products. N doping into the hollow carbon structure can increase the charge density of adjacent carbon atoms and enhance its catalytic activity of ORR/OER. As a result, the Li-O 2 battery using the hollow N-doped carbon sphere as air cathode exhibited an high specific capacity of 18 762 mAh/g (at a current density of 500 mA/g) and remarkable cycling stability of 212 cycles (at a current density of 500 mA/g and limited capacity of 1000 mAh/g), outperforming the carbon material with common structure. This work highlights the importance of air cathode structure and efficient catalyst, provides a new idea for the design of air cathode of Li-O 2 battery, and expands the scope of future research.
研究领域:
材料科学
·
电化学能源存储
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2020
·Vol. 45
·期 5
·7675-7688
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IF 3.741
Qinrong Sun,Nan Zhang,Xiaoping Yu,Fali Ju,Imre Miklós Szilágyi,Yanping Yuan
Summary Phase change materials (PCMs) have limited use in thermal storage because of their poor conductivity and lack of multi driving energy. Therefore, to overcome these problems, polyethylene glycol-calcium chloride/expanded graphite (PEG-CaCl 2 /EG) functional composite PCMs with high electrical and thermal conductivities were synthesized by ligand substitution using PEG-CaCl 2 as the PCM and EG as the highly electrically and thermally conductive framework material. The PEG-CaCl 2 /EG PCMs were thoroughly investigated, and the experimental results revealed the significance of EG in the composite structure, which leads to high electrical conductivity and high thermal conductivity. The resistivity of the functional PCM decreased to 1.67 Ω m, and the thermal conductivity ( k ) increased to 8.4 W/(m K) when the EG content was 10 wt%. In addition, the electro-thermal conversion efficiency of the functional PCM reached 86.9%, and its energy storage could be inspired at low voltages (2.0-5.0 V). The heating and energy storage rates increased with the working voltage and EG content, respectively. Melting-crystallization experiments and electro-thermal cycle tests showed that the functional PCMs had good thermal stability. Therefore, this study provides a new perspective for various fields of energy conversion and storage.
研究领域:
材料科学
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能源工程
✓ 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）