Nano Energy
·
2018
·
IF 13.12
Shaokun Chong,Yifang Wu,Chaofeng Liu,Yuanzhen Chen,Shengwu Guo,Yongning Liu,Guozhong Cao
Potassium-ion batteries (PIBs) have been receiving a great deal of attention owing to abundant and cost-effective potassium resources. However, the key issue is to explore suitable electrode materials for accommodating the large size K-ions reversibly. In this report, K 1.06 Mn 8 O 16 /CNT hybrids are systematically studied for the first time as bifunctional PIBs-electrodes, in which Mn-ions play as the redox center. As the cathode, it exhibits excellent electrochemical kinetics and reversibility, as well as highly structure stability. The cathode displays an unprecedented capacity of 309.4 mA h g −1 at 20 mA g −1 with the energy density of 733.3 Wh kg −1 and outstanding rate performance (187.1 mA h g −1 at 500 mA g −1 ). In addition, the high capacity of 636.6 mA h g −1 at 20 mA g −1 , ultra-long cycling lifespan over 500 cycles and remarkable rate capability can also be acquired when the material was tested as the anode. The extraordinary electrochemical properties are ascribed to the well-developed conductive network and robust microstructure stability. Meanwhile, the symmetrical K-ions full cell exhibits high discharge capacity of 241.0 mA h g −1 at 100 mA g −1 . This work reveals the K-ions storage mechanism in cryptomelane bifunctional electrodes in depth and the fundamental understanding help us open up a new direction for PIBs.
研究领域:
电化学
·
能源材料
·
纳米材料
·
电池技术
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
·
IF 4.175
Zijie Zhang,Qiao Yin,Linlin Xu,Jiaming Zhai,Chun Guo,Yongqiang Niu,Liwei Zhang,Mingliang Li,Hailong Wang,Li Guan,Rui Zhang,Hongxia Lu
The construction of new semiconductor photocatalysts toward the enhancement of photocatalytic activity under visible-light is crucial for a sustainable and clean future. In this paper, cation doping and heterojunction construction were synergistically used to synthesize g-C 3 N 4 matrix composite with a narrow band gap and low recombination rate of photogenerated electron-hole pairs. Potassium-doped-C 3 N 4 (KCN) was used as the matrix to construct semiconductor heterojunction with Cd 0.5 Zn 0.5 S (CZS) by hydrothermal method . The resulting composites were characterized through X-ray diffraction, infrared radiation, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, and ultraviolet–visible diffuse reflectance spectroscopy techniques to examine its phase structure, morphological, valance state and optical properties respectively. The photocatalytic performance of the samples evaluated by H 2 evolution and degrading the Rhodamine B (RhB) aqueous solution. After 12 h hydrothermal reaction at 140 °C, CZS particles uniformly distributed on the KCN matrix. The photocatalytic hydrogen production rate (HPR) of the sample loaded 24 wt% CZS (KCN/CZS 24 wt%) reaches 1.83 mmol/g·h which is 5.6 times of pristine g-C 3 N 4 . The degradation rate constant on RhB of KCN/CZS 24 wt% is ( k = 0.041 min −1 ) 7.9 times higher than g-C 3 N 4 . The enhanced photocatalytic activity can be attributed to the well-matched energy level of KCN and CZS as well as the extended light absorption of the composites.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Yueyue Gao,Yiqian Yao,Chuanwen Zhao,Pu Huang,Yafei Guo,Jian Sun
The capture of CO 2 from flue gas after combustion using solid sorbents is one of the efficient options for reducing CO 2 emissions from fossil fuel-fired power plants. To satisfy the requirement of large quantities flue gas treatment, the CO 2 capture capacities of the solid sorbents must be focused on. In this study, K 2 CO 3 /Al 2 O 3 adsorbents were prepared via spray granulation, achieving an optimal CO 2 adsorption capacity of 1.89 mmol/g at a potassium carbonate loading of 30 wt%. To address the limitations of potassium-based adsorbents, we further enhanced the performance by incorporating polyethyleneimine (PEI), an amine-functionalized material known for its high CO 2 affinity, in the K30Al adsorbent. A series of potassium-amine composite adsorbents were synthesized with varying PEI loadings (1 wt%, 3 wt%, 5 wt%, and 7 wt%). Remarkably, a synergistic effect between K 2 CO 3 and PEI was observed, with the 5 wt% PEI loading yielding the highest CO 2 adsorption capacity of 2.19 mmol/g, representing a 16 % improvement over the unmodified adsorbent. This represents a novel K30Al-P5 composite adsorbent successfully fabricated through deposition of a small amount of PEI onto pre-synthesized K30Al substrate via the spray granulation method. Comprehensive characterization, including adsorption capacity, cyclic stability, and structural properties, revealed that the enhanced performance is attributed to the optimized interaction between K 2 CO 3 and PEI, which facilitates CO 2 chemisorption and diffusion. This study not only demonstrates a significant improvement in CO 2 capture efficiency but also provides a scalable and cost-effective strategy for designing high-performance adsorbents.
研究领域:
环境科学
·
化学工程
·
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
PROGRESS IN REACTION KINETICS AND MECHANISM
·
2024
·Vol. 49
·期 1
·
IF 2.1
Youjun Zhang,Penghui Li,Ruiling Zhang,Xiaopeng Zhang,Hui Cong,Lin Zhao
Potassium-solubilizing bacteria are microorganisms capable of dissolving potassium from potassium-containing minerals, with some species carrying the ability to promote plant growth. This study aims to explore the composition of potassium-solubilizing bacteria from the rhizosphere of wild Lespedeza floribunda, a representative Leguminosae plant, and the mechanisms underlying potassium release. Among the isolated bacteria, the Cupriavidus taiwanensis strain NKK10 exhibited highly efficient potassium solubilizing capacity from potassium feldspar, leading to potassium release of 0.35 and 0.57 mg/mL after 7 d and 14 d, respectively. Microscopic observation showed that the NKK10 cells were able to bind strongly to feldspar, resulting in the formation of a dense biofilm on the mineral surface. As revealed by mRNA sequencing and transcriptional profiling analysis, C. taiwanensis NKK10 drastically remodeled transcriptional profiling analysis in the feldspar medium, with upregulation of critical signaling pathways involved in interspecies interaction between organisms and biofilm formation in response to the stimulus of peptidoglycan synthesis. The results of this study extend our knowledge of the functional microorganisms in Leguminosae rhizospherie soil, and provide insights into the transcriptional regulation of potassium-solubilizing bacteria during the solubilization process.
研究领域:
微生物学
·
植物学
·
分子生物学
✓ 已验证
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2021
·
IF 5.541
Jianjun Xiao,Minjiao Yang,Qingfeng Che,Yingquan Chen,Xu Chen,Haiping Yang,Pietro Bartocci,Francesco Fantozzi,Hanping Chen
The effect of potassium in biomass on the catalytic activity of ZSM-5 zeolite in the fast pyrolysis of biomass was investigated using 2-methylfuran (2-MF) as the typical model compound. The mechanism of action of potassium was explored in detail, along with the physicochemical properties of ZSM-5, including crystallinity, pore structure, and surface acidity. The physicochemical properties of ZSM-5 deteriorated to varying degrees after being tainted with different potassium sources (KOH, K 2 CO 3 , KAc, and KCl). Compared with neutral KCl and strong alkali KOH, K 2 CO 3 , and KAc, with weaker alkalinity but larger crystal structure, exerted a larger influence on ZSM-5. Changes in ZSM-5 tainted with K 2 CO 3 were the greatest, and crystallinity, surface area, acidity, and the corresponding yields of valuable aromatic hydrocarbons and gas products, all declined significantly, compared with raw ZSM-5. When the amount of K(CO 3 2− ) on ZSM-5 was less than 0.5 wt%, only minor (<10 %) changes were observed in crystallinity and surface area, but total acidity decreased by over 30 percent. The conversion of 2-MF was increased using ZSM-5 tainted with less than 0.5 wt% K(CO 3 2- ) and less liquid oxygenated compounds and more CO 2 were produced. Appropriate total acidity, adjusted by a tiny amount of K 2 CO 3 , could promote deoxygenation to CO 2. However, the decarbonylation reaction was inhibited, causing a negative effect on monocyclic aromatic hydrocarbons, which was attributed to the large-scale loss of both acidity and physical structure of ZSM-5 caused by more than 1.0 wt% K(CO 3 2- ).
研究领域:
化学工程
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2015
·Vol. 5
·期 4
·1897-1910
·
IF 2
Shiqiang Zhao,Guizhuan Xu,Chun Chang,Shuqi Fang,Ze Liu,Fengguang Du
A series of metal-modified phosphotungstates were prepared and performed for direct synthesis of ethyl levulinate from fructose in ethanol. Considering the cost of catalysts, catalytic activity of catalysts, and easy separation of catalysts together, K-HPW-1 was chosen as the most suitable catalyst for synthesis of ethyl levulinate from fructose. A high ethyl levulinate yield of 64.6 mol% was obtained at 150 °C within 2 h in ethanol. The introduction of low polar toluene as a co-solvent improved the yield of ethyl levulinate to 68.7 mol%. The recovered catalyst remained high activity with the yield of ethyl levulinate converted from fructose above 50 mol% after being used five times. Moreover, the generality of the catalyst was further demonstrated by glucose, sucrose, inulin, and cellulose with ethyl levulinate yielding 14.5, 35.4, 52.3, and 14.8 mol%, respectively.Keywords:ethyl levulinate;carbohydrates;potassium phosphotungstate
研究领域:
催化化学
·
可再生化学
✓ 已验证
产品关联
DOI
高影响因子
ENZYME AND MICROBIAL TECHNOLOGY
·
2022
·
IF 3.705
Tao Tian,Hao Zhang,Feng-Qing Yang
A rapid, portable, and cost-effective method using personal glucose meter (PGM) for quantitative analysis of hydrogen peroxide (H 2 O 2 ) was established based on ascorbate oxidase (AAO)-catalyzed reaction for the first time. Ascorbic acid (AA) can rapidly reduce ferricyanide (K 3 [Fe(CN) 6 ]) to ferrocyanide (K 4 [Fe(CN) 6 ]) in the glucose test strip and transfer electron to the electrode to generating a PGM detectable signal. Thus, the concentration of AA can be directly determined by the PGM as simple as measuring the blood glucose. On the other hand, AAO can catalyze the reduction of H 2 O 2 and produce an enzyme-peroxide complex, which decreases the yields of dehydroascorbic acid formed by the oxidation of AA, resulting in the increase in PGM detectable signal of residual ascorbic acid (re-AA). Therefore, the concentration of H 2 O 2 is proportional to the concentration of re-AA. After optimization of the experimental conditions, the developed method can be used to detect H 2 O 2 at linear range of 2.5–5 × 10 3 μM with the quantification limit of 2.5 μM. In addition, the satisfactory spiked recoveries (95.3–108.9 %) of real samples (i.e., tap water, contact lens solution, medical hydrogen peroxide, and normal human serum) confirm its feasibility for practical applications. In short, this study provides a feasible PGM-based method for H 2 O 2 detection with simple operations.
研究领域:
分析化学
·
生物化学
·
环境科学
·
医学诊断
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2018
·
IF 5.091
Xianglong Huang,Qiuju Xu,Wei Gao,Tingting Yang,Renming Zhan,Jianhua Deng,Bingshu Guo,Mengli Tao,Hongdong Liu,Maowen Xu
In this work, porous carbon matrix derived from metal-organic frameworks is synthesized by a facile carbonation process for confining element selenium. The Se/nitrogen-doped porous carbon composite is applied as the cathode for rechargeable K-Se batteries for the first time. The abundant and hierarchical porous structure is advantageous in overcoming the volume expansion problem caused by polyselenides during discharge-charge process. The in-situ nitrogen-doped porous carbon enhances electronic conductivity of the cathode composite material. The electrochemical result shows that the as-obtained Se/nitrogen-doped porous carbon composite with Se content of 53% delivers good rate capacity with coulombic efficiency of nearly ∼90% and a reversible cycling capacity of 327 mA h g −1 at 0.2 C, maintaining about 130 mA h g −1 even after 100 cycles.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF APPLIED ELECTROCHEMISTRY
·
2024
·
IF 2.4
Li Mei,Du Rui,Wei Hedi,Chen Jiayi,Liu Rugeng,Zhang Meng,Han Wei
In order to investigate the influences of the additive (KF) on electrochemistry and deposit morphology of Pr, various electrochemical techniques were used to comparative investigate the electroreduction potential and diffusion coefficient of Pr 3+ and kinetic properties of Pr 3+ /Pr in LiCl–KCl-PrCl 3 before and after the addition of KF at different molar concentration ratios of F − to Pr 3+ ( k ). Cyclic voltammetry, square wave voltammetry, and reverse chronopotentiometry results showed that the value of k ( k = 0, 1, 2, 3, and 4) had no effect on reduction mechanism of Pr 3+ . With the increase of k , the reduction peak potential moved in the negative direction, the diffusion coefficient decreased, and diffusion activate energy increased. Meanwhile, the exchanged current densities ( j 0 ), charge transfer resistances ( R ct ), and activate energies ( E a ) were measured at different k by linear polarization technique, which illustrated that with the increase of k , j 0 gradually decreased, and E a and R ct increased. Furthermore, the electrochemical preparation of Pr aided by KF was explored by potentiostatic electrolysis at different k , and the products were characterized by XRD, SEM, and EDS, which indicated that with the increase of k , the morphology of metallic Pr changed from slender needles to granular. Graphical abstract
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 ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Jin Chen,Chun-Li Hu,Yi-Lin Li,Qian-Qian Chen,Bing-Xuan Li,Jiang-Gao Mao
Herein, we reported two alkali metal molybdenum(VI) iodates, namely, NaMoO 3 (IO 3 ) and γ-KMoO 3 (IO 3 ) with 1D and 3D [MoO 3 (IO 3 )] − anionic architectures, respectively. The novel 1D chain in NaMoO 3 (IO 3 ) and the 3D network in γ-KMoO 3 (IO 3 ) are constructed by the 0D Λ-shaped cis -[MoO 4 (IO 3 ) 2 ] 4− building units interconnected by bridging IO 3 − anions as well as the corner-sharing of oxo anions. Importantly, the polar γ-KMoO 3 (IO 3 ) exhibits a very large second-harmonic generation (SHG) effect of 12 × KH 2 PO 4 (KDP) under 1064 nm laser radiation, a high laser-Induced damage threshold value (52 × AgGaS 2 ), and a moderate birefringence of 0.087@1064 nm, whereas the centrosymmetric NaMoO 3 (IO 3 ) has a large birefringence of 0.208@1064 nm. This study further proves the useful route of exploring promising optical materials via assembling the 0D basic building units into higher dimensional anionic architectures.
研究领域:
无机化学
·
材料科学
·
光学
✓ 已验证
DOI
高影响因子
Frontiers of Chemical Science and Engineering
·
2013
·Vol. 7
·期 3
·297-302
·
IF 0
Xiao Qiang,Tang Xiaodan,Liu Yefeng,Zhong Yijun,Zhu Weidong
A comparison study has been conducted on the strategies for synthesizing nanocrystalline Li 2 ZrO 3 and Kdoped Li 2 ZrO 3 absorbents for CO 2 capture at high temperatures, including solid-state and liquid-phase methods, citrate route, and starch-assisted sol-gel method combined with freeze-drying technique. The absorption properties, including uptake rate and absorption capacity, of synthesized absorbents were investigated by thermogravimetric analysis (TGA) at different CO 2 partial pressures. The nanosized Li 2 ZrO 3 crystals synthesized by the citrate route exhibit a faster uptake and a higher, nearly stoichiometric absorption capacity than those synthesized by the solid-state and liquid-phase methods. The doping of K into Li 2 ZrO 3 can significantly improve the uptake rate of CO 2 , especially at low CO 2 partial pressures. For the synthesis of K-doped Li 2 ZrO 3 , the citrate route has poor reproducibility and scalability, whereas the starch-assisted sol-gel method combined with freeze-drying technique is reproducible and easily scaled up, and the thus synthesized absorbents possess excellent CO 2 capture properties.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
ADVANCED POWDER TECHNOLOGY
·
2025
·
IF 4.2
Jingjing Zou,Yiping Sun,Shuo Liang,Zhongrui Shi,Guanghe Li,Chunbin Guo
This study introduces a novel process for recovering Al 2 O 3 from coal fly ash (CFA), utilizing potassium persulfate (K 2 S 2 O 8 ) as an activator, and explores the decomposition behavior of both crystalline and amorphous alumina phases within CFA. The experiment involved mixing K 2 S 2 O 8 with CFA in K 2 S 2 O 8 /Al 2 O 3 molar ratios ranging from 0.5:1 to 4:1, followed by calcination at varying temperatures and durations to optimize alumina extraction. The results indicated that the alumina extraction efficiency of 91 % was achieved with a molar ratio of 3:1 (K 2 S 2 O 8 /Al 2 O 3 ), calcination temperature of 405 °C, and reaction time of 2 h. X-ray photoelectron spectroscopy, scanning electron microscopy, and reaction kinetics were employed to analyze the reaction mechanism. The findings revealed that K 2 S 2 O 8 preferentially reacted with the amorphous alumina phase, leading to the breakage of Al–O–Si bonds. The release of SO 2 and O 2 during the reaction further facilitated the breakdown of the crystalline phase by disrupting aluminum–oxygen tetrahedra. Simultaneously, the silicon-oxygen tetrahedra decomposes and forms SiO 2 gel layer, wrapping the remaining aluminum oxygen octahedron, thus preventing further alumina extraction. This study contributes to a deeper understanding of the decomposition behavior of crystalline and amorphous alumina phases in CFA during sulfate roasting. The findings provide a theoretical foundation for refining alumina recovery processes and offer significant improvements to existing sulfate roasting methods.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 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）