Science China-Technological Sciences
·
2022
·Vol. 65
·期 10
·2337-2347
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IF 3.903
Hou ShengPing,Zhang Da,Xie ZhiPeng,Kang Yao,Tang ZhengGang,Dai YongNian,Lei Yong,Chen Jian,Liang Feng
As the quantity of waste tires increases, more pyrolysis carbon black (CBp), a type of low value-added carbon black, is being produced. However, the application of CBp has been limited. Therefore, it is necessary to identify and expand applications of CBp. This work focuses on the preparation of activated carbon (AC) from CBp using the physicochemical activation of carbon dioxide (CO 2 ) and potassium hydroxide (KOH). Thereafter, AC is applied to the electrode of the electrical double-layer capacitor (EDLC). The AC prepared by CO 2 /KOH activation exhibited a hierarchical pore structure. The specific surface area increased from 415 to 733 m 2 g −1 , and in combination with low ash content of 1.51%, ensured abundant ion diffusion channels and active sites to store charge. The EDLC comprising the AC (AC-2) electrode prepared by excitation of CO 2 (300 sccm) and KOH had a reasonable gravimetric specific capacitance of 192 F g −1 at 0.5 A g −1 , and exhibited a good rate capability of 73% at 50 A g −1 in a three-electrode system. Moreover, the EDLC device comprising the AC-2 electrode delivered excellent cycling stability (capacitance retention of 106% after 10000 cycles at 2 A g −1 in a two-electrode system). Furthermore, a symmetric supercapacitor based on an AC electrode that exhibits a supreme energy density of 4.7 Wh kg −1 and a maximum power density of 6362.6 W kg −1 is demonstrated.
研究领域:
材料科学
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环境科学
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能源工程
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DOI
高影响因子
Carbon Letters
·
2020
·Vol. 30
·期 6
·657-665
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IF 1.992
Li Jiajia,Hu Jiajun,Wang Kai,Xia Hongyan
Effective processing and use of coal slime is of great significance to protect the environment and save resources. Different coal slimes (untreated with 43 wt% ash content, crushed and flotation treated with 10 wt% ash content, and pre-carbonized) were activated with KOH to prepare porous activated carbon. The results show the activated carbon prepared from coal slime with 10 wt% ash had high specific surface area (3037 m 2 /g) and pore volume (1.66 cm 3 /g), which was ascribed to the suitable contents of minerals as template and oxygen-containing functional groups. Electrochemical measurements exhibited the best specific capacitance of 220 F/g at 0.1 A/g and the cycle stability of over 100% capacitance retention after 1000 cycles at 5 A/g in 6 M KOH solution. Due to the high specific surface area, superior electrochemical performance, and facile and low cost, developing highly porous activated carbon for supercapacitors is one alternative way for effective use of coal slime waste.
研究领域:
材料科学
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环境工程
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能源存储
·
碳材料
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电化学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
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
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产品关联
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2026
·
IF 4.6
Shaolong Liu,Zhifeng Su,Zhiming Qiu,Xitao Guo,Minghua Liu,Yurong Yan
Biomass-derived porous carbon holds great promise as an electrode material for supercapacitors due to its low cost and sustainability. However, single-activator strategies typically fail to achieve microporous-mesoporous structure with high specific surface area (SSA) and micropore volume of such carbon materials, thereby limiting their capacitive performance. Therefore, inspired by the pyrolysis behavior of sodium lignosulfonate, we innovatively propose a novel activation system for preparing N/O/S co-doped biomass microporous-mesoporous carbon (SLCA): utilizing chitosan carbon and sodium lignosulfonate as self-doping carbon sources, potassium hydroxide as the primary activator, and sodium lignosulfonate as the self-templating activator. The microporous volume is a key factor influencing specific capacitance. Specifically, the SLCA-700 (activated at 700 °C) has a microporous-mesoporous structure with abundant N/O/S heteroatoms doping and a SSA of 2378.7 m 2 ·g −1 , and achieves a high micropore volume of 0.84 cm 3 ·g −1 , which is 0.24 cm 3 ·g −1 higher than that of the KOH activation system alone. Furthermore, the SLCA-700 electrode exhibits an outstanding specific capacitance of 305.9 F·g −1 at 0.5 A·g −1 , and supercapacitor shows excellent cycling stability (97.0% capacitance retention after 10,000 cycles). This study proposes a dual activation mechanism for preparing microporous-mesoporous carbon with a high SSA, providing a viable strategy for producing high-performance supercapacitor electrode materials.
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高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2026
·
IF 12.5
Kai Tang,Haoqian Chen,Yuxiang Wu,Xiaoshan Li,Cong Luo,Liqi Zhang,Fan Wu
Selective confinement of KOH in micropores eliminates surface KOH aggregation. • Fast kinetics and low-temperature regeneration (80–100 °C). • 89% capacity retention over 50 cycles with active species stably locked in micropores. • Confined water enables dry-air chemisorption with fully reversible humidity tolerance. Direct air capture (DAC) of CO 2 requires sorbents that combine high uptake, fast kinetics, and low-energy regeneration. Here, we report a selective confinement strategy to fabricate a KOH-functionalized activated carbon cloth (KOH-O-ACC) that achieves these goals, delivering both fast adsorption kinetics and low-temperature regenerability. By selectively removing surface-deposited species while preserving KOH confined within the micropores, this approach shifts the active species from undesirable surface accumulation into the micropores. The resulting sorbent delivers a CO 2 uptake of 0.358 mmol/g under realistic DAC conditions (400 ppm CO 2 , 30 °C) and can be regenerated at low temperatures of 80–100 °C. Over 50 adsorption-desorption cycles, the material retains approximately 89% of its initial capacity and exhibits superior oxidative stability compared to amine-based sorbents. Preliminary mechanistic insights suggest that the strong chemisorption under dry conditions may be related to confined water retained within the material. This work demonstrates that precise spatial control of active species is a critical design principle for developing energy-efficient and durable DAC sorbents.
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DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2025
·
IF 7.7
Bing Liu,Weihao Li,Yiwen Huang,Wenli Qin,Min Wang,Yang Jia,Hanqing Xu,Liyin Qu,Hongbin Jiang,Chao Wang,Zengling Ma
The overuse of the broad-spectrum antibiotic tetracycline hydrochloride (TCH) in humans and animals poses serious risks to environmental safety and human health. Adsorption offers a convenient yet effective way to lower its concentration. The KOH-activated Chlorella vulgaris -derived biochar (CVBC) was co-doped with Ca or P using a simple impregnation-pyrolysis method to modify its physicochemical properties. The P-doped KOH-activated Chlorella vulgaris -derived biochar (P-KOH/CVBC) achieved a maximum TCH adsorption capacity of 662.91 mg/g (Langmuir isotherm model, initial TCH concentration 100 mg/L, 303 K, dosage of 200 mg/L), which is higher than most of the adsorbents. Moreover, P-KOH/CVBC exhibited a superior pH buffering capacity and enhanced resistance to ionic interference. This is because the adsorption mechanism of TCH onto P-KOH/CVBC is dominated by π-π EDA interactions, whereas that for Ca-KOH/CVBC is primarily through metal complexation. The π-π EDA interactions not only enhance the adsorption capacity of P-KOH/CVBC for TCH but also contribute to its strong resistance to ionic interference. Notably, this study is the first to reveal the indispensable role of ultra-microporosity (pore size ≤ 0.7 nm) in the TCH adsorption process. Density functional theory calculations revealed that the ultra-micropore structure significantly enhanced the interaction between the biochar and TCH, as compared with super-micropores (0.7 nm < pore size < 2 nm), thereby facilitating the adsorption process. Therefore, this research demonstrated that P doping enhances TCH adsorption on KOH-activated biochar and elucidated the ultra-microporosity-mediated adsorption pathways.
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DOI
PubMed
高影响因子
SN Applied Sciences
·
2021
·Vol. 3
·期 1
·1-10
·
IF 0
Li Yaxing,Yuan Shenfu
In this study, humic acids (HAs) were extracted from Chinese lignite by adding KOH to a NaOH solution. The extraction yield of HAs was found to improve because of the synergistic effect imparted by the alkali mixture of sodium hydroxide (NaOH) and potassium hydroxide (KOH). The maximum yield was obtained at 150 min by adding the mixture of 0.750 M NaOH + 0.710 M KOH to Xianfeng lignite at 80 °C. The potassium (K), sodium (Na), nitrogen (N), oxygen (O), and iron (Fe) contents were determined by X-ray diffraction, scanning electron microscopy, and proximate and ultimate analysis. The oxygen-containing functional groups in HAs were identified by Fourier transform infrared spectroscopy. The addition of KOH resulted in higher oxygen/carbon and nitrogen/carbon ratios and oxygen-containing functional groups, as compared with that in NaOH alone. The extractants containing KOH could release HAs with a higher proportion of K, Fe, N contents, which is beneficial for HAs fertilizers prepared from the lignite. The release of the nutrients (K, Fe, N) which are essential for the crops is determined by the KOH dosages.
研究领域:
化学
·
农业科学
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产品关联
DOI
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Xiaoyu Tian,Minghua Zhou,Chaolin Tan,Ming Li,Liang Liang,Kerui Li,Pei Su
N-doped carbon aerogel (CA) was prepared by one-pot template-free synthesis and chemically activated with potassium hydroxide (KOH). KOH activation highlighted the structural superiority with increased BET surface area and hierarchically porous structure (especially micropores), and also significantly influenced active nitrogen species and oxygen functional groups (C O C and COOH) content. With KOH increasing, pyridinic N content increased, while pyrrolic N content decreased. Oxygen reduction reaction (ORR) activity showed a positive linear correlation with pyridinic N content but decreased with pyrrolic N content increasing. C O C and COOH content increased after activation, and then decreased with KOH increasing. The reduced C O C and COOH content of CA-KOH guaranteed a lower H 2 O 2 yield for higher microbial fuel cell (MFC) efficiency. CA-10KOH (mass ratio of KOH to CA was 10) exhibited outstanding performance with the highest maximum power density (967 ± 34 mW m −2 ), which was 37.4%, 55.2% and 283.7% higher than platinum (Pt/C), activated carbon (BET surface area of 2276 m 2 g −1 ) and CA. The outstanding performance of CA-10KOH was attributed to the conjunct effect of superior BET surface area (1827 m 2 g −1 ), increased micropores, the highest pyridinic N (0.26 at.%), the lowest pyrrolic N content and reduced C O C and COOH content. Overall, KOH activated CA is a promising metal-free cathode catalyst for high performance in MFCs.
研究领域:
环境科学
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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
JOURNAL OF POWER SOURCES
·
2014
·
IF 5.211
Guofu Ma,Jiajia Li,Kanjun Sun,Hui Peng,Jingjing Mu,Ziqiang Lei
A gel polymer PVA–KOH–K 3 [Fe(CN) 6 ] is prepared by potassium hydroxide and potassium ferricyanide doped polyvinyl alcohol, and a solid-state supercapacitor is assembled using the gel polymer as electrolyte and separator, activated carbons as electrode. The gel polymer exhibits flexible, high ionic conductivity and wide potential properties. The electrochemical properties of the supercapacitor are investigated using cyclic voltammetry , galvanostatic charge/discharge, and impedance spectroscopy techniques. The electrode specific capacitance of the supercapacitor can be as high as 430.95 F g −1 , and after 1000 cycles at a current density of 1 A g −1 it still remains higher than 380 F g −1 . The energy density and power density of the supercapacitor reach 57.94 Wh kg −1 and 59.84 kW kg −1 , respectively. These novel flexible gel polymers are desirable for applications in supercapacitor devices.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2025
·Vol. 172
·期 9
·090533
·
IF 3.3
Baoning Zhu,Wenjun Zhu,Zijun Sun,Qijun Zhong,Jiale Chen,Zehong Tang,Xiaohui Ren,Xiong He,Jinghua Liu
The growth of sustainable energy storage drives the need for advanced supercapacitors. Porous carbon materials obtained from biomass resources are promising electrode candidates owing to their cost effectiveness and structural tunability. We propose an efficient conversion strategy by synergistically integrating N/O/V heteroatom doping with KOH activation, using waste sugarcane bagasse as the precursor. The prepared porous carbon material a unique wrinkled worm-like nanoporous sheet morphology, with partial transformation into carbon spheres measuring 100–200 nm in size. The resulting material demonstrates an outstanding specific capacitance of 434.4 F g−1 at a current density of 1 A g−1. Additionally, the supercapacitor assembled with this material delivers an energy density of 21.0 Wh kg−1 at a power density of 250 W kg−1. This study outlines a feasible method for converting biomass waste into high-performance electrode materials.
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DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2025
·
IF 7.7
Yadi Jia,Pinjing He,Fan Lü,Wei Peng,Hua Zhang,Khamphe Phoungthong
In response to the growing challenge of photovoltaic waste management, developing sustainable and value-added treatment strategies is imperative. In this study, ethylene-vinyl acetate (EVA) resins sourced from waste photovoltaic modules and virgin materials were utilized for the production of hierarchical porous carbon (HPC) and methane-rich combustible gas via autogenic pressure pyrolysis coupled with KOH activation. Temperature-dependent pyrolysis revealed that 700 °C was the optimal condition, yielding pyrolysis gas with a high methane content (43.39 vol%) and producing graphitized carbon spheres. Subsequent KOH activation generated HPC with a large specific surface area of 765.4 m 2 /g. When applied as a supercapacitor electrode in 6 mol/L KOH electrolyte, the HPC exhibited a high specific capacitance of 152 F/g at 0.2 A/g. Additionally, EVA resins with higher vinyl acetate content and melt index (MI) produced greater amounts of methane and pyrolytic carbon, while the resins with lower MI values showed enhanced reactivity toward chemical activation. This work offers a green and efficient route for the high-value recycling of EVA in PV waste and contributes to the sustainable synthesis of advanced HPC materials for energy storage applications.
研究领域:
环境科学
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材料科学
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能源化学
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废弃物资源化
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电化学储能
·
高分子材料工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2015
·
IF 3.313
Yang Fan,Peifang Liu,Bing Zhu,Shufang Chen,Kaili Yao,Ran Han
The tree biomass acacia gum was used as a natural precursor to synthesize microporous carbon for energy storage application . The microporous carbons were synthesized by hydrothermal carbonization of acacia gum at 180 °C, and subsequent activation by KOH at temperatures in the range of 700−900 °C. The carbon materials possess high surface area and well-controlled pore size distribution . Moreover, the porosity can be finely tuned by modifying the activation temperatures. The influence of the porosity of the carbon materials on their capacitive performance was investigated. The superior charge storage capability with specific capacitance up to 272 F g −1 at current density of 1 A g −1 in 6 M KOH was achieved by the as-prepared microporous carbons.
研究领域:
材料科学
·
能量存储
·
电化学
✓ 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）