INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2022
·
IF 7.139
Mengzhu Li,Ting Wang,Xuan Chen,Xiuyuan Ma
The efficient use of lignocellulosic biomass resources is of great significance to solve environmental pollution and energy crisis. Therefore, the understanding of the reactivity of lignin, hemicellulose , and cellulose , which are the major components of lignocellulosic biomass, on chemical and hydrogen conversion is necessary. So combined with proton exchange membrane electrolysis cell , using polyoxometalate (POM) as the oxidizing agent and electron stockpile carrier, the cyclic electrolytic hydrogen production and degradation of lignin, hemicellulose, and cellulose have been researched in detail. Among them, lignin degraded the best (96.81%), and the average Faradaic efficiency of the herein system was also the highest (95.93%). These results exhibit high conversion efficiency from electric energy to hydrogen energy . Simultaneously, without harsh conditions, lignin is mainly degraded to vanillin , hemicellulose is mainly converted to ester compounds, and cellulose is mainly converted to alcohol compounds, which provides an experiment basis for future chemical conversion.
研究领域:
能源生物学
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环境科学
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DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2023
·
IF 22.1
Guoqiang Zhang,Yangsen Xu,Jinyu Zhu,Yongliang Li,Chuanxin He,Xiangzhong Ren,Peixin Zhang,Hongwei Mi
The role of exciton dissociation in charge separation dominated by in-plane crystallinity has been rarely addressed, although it is the decisive step of polymeric carbon nitride (CN) photocatalysis . Here, taking ten kinds of crystalline carbon nitride (CCN) as examples, the relationship between exciton dissociation, carrier mobility, conductivity, charge separation and photocatalytic activity under different in-plane crystallinity has been investigated. Although the in-plane crystallinity dominates charge separation and photocatalytic activity, it does not significantly reduce excitons binding energy (EBE) or improve exciton dissociation efficiency (EDE), only decreasing by 1.5 meV and increasing by 2.3 %, respectively. It is the greatly improved carrier mobility and conductivity that are more responsible for the increased charge separation and photocatalytic activity than the slight change in EDE. To our knowledge, this is the first reported case of overall water splitting in CCN of poly(heptazine imide) structure, resulting from the optimized in-plane crystallinity.
研究领域:
材料科学
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化学
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光催化
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产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2023
·
IF 3.8
Huijun Shang,Hengli Li,Weijun Li,Feng Pan,Zhan Du
ABSTRACT In order to avoid the formation of η phase (W 6 Co 6 C or W 3 Co 3 C) that adversely affects the sintering process and its products in the preparation process of ultra-fine WC-Co powder, a technical route of pre-reduction of WO 3 –Co 3 O 4 to WO 2 –Co and then deep reduction carbonization to WC-Co powder has been proposed. This study mainly investigates the influence of gas partial pressure on the pre-reduction process of WO 3 –Co 3 O 4 under a mixed atmosphere of H 2 –C 2 H 4 –Ar at 600 °C and establishes the kinetic equations of pre-reduction and carbon evolution. The results indicate that increasing the partial pressure of hydrogen is conducive to the rapid and complete conversion of WO 3 to WO 2 . High carbon content can be generated by the deposition of C 2 H 4 , and it hinders the diffusion of the reducing gas; WO 3 still cannot be completely reduced to WO 2 as the partial pressure of C 2 H 4 increases to 60%. For the carbon evolution of C 2 H 4 , the carbon amount is positively related to the H 2 partial pressure, but it shows the highest amount and evolution rate when the ethylene partial pressure is 20%. Based on the reduction rate curves of WO 3 and carbon evolution rate curves of C 2 H 4 , the rate equations of pre-reduction and carbon evolution of WO 3 –Co 3 O 4 system at 600 °C are established. The pre-reduction reaction belongs to the first-order reaction, and its equation is expressed as follows: r = − d w WO 3 d t = 9 ± 0.15 × 1 0 − 2 P H 2 0.44 P C 2 H 4 0.57 The carbon deposition rate equation of C 2 H 4 can be expressed as follows: r ' = d c C d t = r f − r b ≅ 7.35 × 1 0 − 2 × P C 2 H 4 0.31
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高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
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IF 8.6
Jialong Wang,Longbin Chen,Yaodong Yang,Tiancheng Hou,Wei-Feng Rao
Piezoelectric catalytic seawater hydrogen production is one of the most crucial and potential hydrogen production strategies. However, the low surface activity and the high carrier recombination rate limit the further improvement of catalytic efficiency. To solve this problem, we prepared SrBi 4 Ti 4 O 15 (SBTO) and FeS 2 (FS) heterojunctions, which can effectively utilize the valence state transformation cycle between Fe 2+ and Fe 3+ to improve the surface activity and maintain carrier separation. This mechanism of Fe 2+ and Fe 3+ conversion is similar to the well-known Fenton reaction. It was confirmed by electrochemical measurements that with the help of FeS 2 , SBTO possessed a stronger piezoelectric current response and faster carrier transfer rate. Piezoelectric catalytic seawater splitting H 2 evolution rate of SBTO-25 %FeS 2 could reach 31 mmol g -1 h −1 , which is higher than that of other piezoelectric materials in similar conditions. Our findings provide valuable insights for further improving the efficiency of seawater hydrogen production efficiency.
研究领域:
材料科学
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能源化学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2023
·Vol. 19
·期 50
·2304674
·
IF 13.3
Kailai Zhang,Xiaodong Sun,Haijun Hu,Ge Yan,Anqi Qin,Yali Ma,Hongwei Huang,Tianyi Ma
Mechanical energy driven piezocatalytic hydrogen (H 2 ) production is a promising way to solve the energy crisis . But limited by the slow separation and transfer efficiency of piezoelectric charges generated on the surface of piezocatalysts , the piezocatalytic performance is still not satisfactory. Here, defect engineering is first used to optimize the piezocatalytic performance of microcrystalline cellulose (MCC). The piezocatalytic H 2 production rate of MCC with the optimal defect concentration can reach up to 84.47 µmol g −1 h −1 under ultrasonic vibration without any co-catalyst, which is ≈3.74 times higher than that of the pure MCC (22.65 µmol g −1 h −1 ). The enhanced H 2 production rate by piezoelectric catalysis is mainly due to the introduction of defect engineering on MCC, which disorders the symmetry of MCC crystal structure, improves the electrical conductivity of the material, and accelerates the separation and transfer efficiency of piezoelectric charges. Moreover, the piezocatalytic H 2 production rate of MCC with the optimal defect concentration can still reach up to 93.61 µmol g −1 h −1 in natural seawater, showingits commendable practicability. This study presents a novel view for designing marvelous-performance biomass piezocatalysts through defect engineering, which can efficiently convert mechanical energy into chemical energy .
研究领域:
材料科学
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能量转换
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催化
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PHOTOCHEMISTRY AND PHOTOBIOLOGY
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2023
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IF 3.3
Xing Liu,Longxin Hu,Yujie Zhang,Hua Lai,Gang Peng,Junhua Li,Rongying Zeng,Zhengji Yi
In the present work, carbon nitride quantum dots (CNQDs)-modified cobalt phosphate (CoPi) composites CNQDs/CoPi- x ( x = 1, 2, 3) were prepared at room temperature and characterized by FTIR, XRD, UV–Vis DRS, EIS, SEM, TEM/HR-TEM, XPS, and N 2 gas adsorption. The morphologies and surface areas of CNQDs/CoPi- x have no remarkable change after modification of CNQDs, compared with pure CoPi. The obtained CNQDs/CoPi- x shows enhanced activity and stability of photocatalytic H 2 evolution compared to pure CoPi using Eosin Y (EY) as a sensitizer and triethanolamine as an electron donor. The CNQDs/CoPi-2 possesses the highest hydrogen evolution rate, 234.5 μmol h −1 g −1 , upon visible light, which outshines that of CoPi by 2.4 times. It was believed that the enhanced photocatalytic performances of the CNQDs/CoPi-2 could result from the boosted electron transfer from radical EY ·− to CNQDs/CoPi-2 by the employment of CNQDs; in addition, the visible-light activity of CNQDs contributes to hydrogen evolution. The mechanism of photocatalytic hydrogen production was discussed. This study may contribute toward the development of production of “green hydrogen” using solar.
研究领域:
材料科学
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能源化学
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环境科学
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产品关联
DOI
PubMed
高影响因子
Chemosensors
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2023
·Vol. 11
·期 4
·250
·
IF 4.2
Liang Wang,Jianxin Yi
Monitoring the concentration of hydrogen is very important as it is a flammable and explosive gas. Non-Nernstian potentiometric hydrogen sensors hold promising potentials for the sensitive detection of hydrogen. This paper reports the improved H2-sensing performance of a mixed oxide ion-electron conducting (MIEC) Pr0.1Ce0.9O2−δ(PCO) electrode using Fe2O3surface modification. The Fe2O3-modified PCO exhibited a high response of −184.29 mV to 1000 ppm H2at 450 °C. The response values exhibited a linear or logarithmic dependence on the H2concentration for below or above 20 ppm, respectively. A sensitivity of −74.9 mV/decade in the concentration range of 20–1000 ppm was achieved, and the theoretical limit of detection was calculated to be 343 ppb. Moreover, a power-law relationship between the response time and the concentration value was also found. Electrochemical impedance analyses revealed that the excellent H2-sensing performance may be attributed to the large ratio of the electrochemical activity of the hydrogen oxidation reaction (HOR) over the oxygen exchange reaction (OER). In addition, the distribution of relaxation time (DRT) results reveal that the enhanced electrochemical kinetics caused by H2presence in air is mainly related to acceleration of the electrode surface processes.Keywords:solid electrolyte;potentiometric gas sensor;Fe2O3surface modification;electrochemical activity
研究领域:
材料科学
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传感器技术
✓ 已验证
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2023
·Vol. 10
·期 11
·3255-3262
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IF 7
Shiyu Zhou,Wenjun Yan,Min Ling,Chengdu Liang
Metal oxide semiconductor-based chemiresistors have been facing challenges in achieving low-temperature hydrogen sensing at the ppb level. The oxygen vacancy is considered to play a vital role in gas sensing properties. However, a nonstoichiometric metal oxide semiconductor with efficient and controllable oxygen vacancies is not easily accessible. Herein, a facile solution reduction method of NaBH4 was developed to modulate the oxygen vacancies of ZnO nanosheets. The systematic characterization studies confirm the successful introduction of oxygen vacancies in ZnO samples. The gas sensing investigations illustrate that the construction of controlled oxygen vacancies greatly enhances the hydrogen sensing properties of ZnO nanosheets, especially a significantly reduced operating temperature (150 °C) with a higher response (∼38.2 for 200 ppm), a calculated limit of detection (55 ppb) and a quick recovery speed (only 6 s). The increased molecule adsorption and narrower band gap generated by controlled oxygen vacancies contribute to their superior sensing properties. The oxygen vacancy engineering strategy of pure metal oxide semiconductor-based materials shows great potential for creating low-temperature high-response sensors.
研究领域:
材料科学
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传感器技术
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产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2025
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IF 5.6
Chen Liu,Siwu Li,Lin Li,Qiyue Luo,Liang Ming,Ziling Jiang,Ziyu Lu,Miao Deng,Jie Yang,Shijie Cheng,Chuang Yu
The sulfide electrolyte-based all-solid-state batteries with high-nickel layered oxide cathodes face significant challenges due to the narrow electrochemical window of sulfides and severe side reactions caused by direct contact with high-voltage oxide cathode materials such as LiNi 0.9 Mn 0.05 Co 0.05 O 2 (NCM90). Here, we successfully synthesized Li 3 InCl 6 (LIC) halide electrolytes through ball-milling followed by annealing method, achieving the ionic conductivity of 2.0 mS cm −1 at room-temperature. The interface between this electrolyte and NCM90 cathode material without any interface modification is stable. By introducing the LIC electrolyte layer, the NCM90/LIC+Cl1.5/Li-In battery exhibits significantly improved electrochemical performance at different temperatures, particularly in terms of initial discharge capacity. Notably, the battery demonstrates outstanding discharge capacity and cycling stability at low temperatures. Experimental investigations reveal that the introduction of the LIC electrolyte with high oxidation potential facilitates the H2-H3 phase transition in NCM90 during high-voltage operation, which is critical for enhancing the discharge capacity. This work provides fundamental insights into interfacial engineering strategies for high-voltage sulfide-based all-solid-state battery systems.
研究领域:
储能
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材料科学
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电化学
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固态电池技术
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产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
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2018
·
IF 3.956
Qilei Yang,Ang Cao,Na Kang,Kang An,Zhao-Tie Liu,Yuan Liu
The catalyst for direct ethanol synthesis (DES) from syngas was investigated in this work, which is Co/La 2 O 3 -doped La 4 Ga 2 O 9 . The catalyst was prepared by using LaCo 1−x Ga x O 3 with perovskite phase as the precursor to intensify the interaction in the elements of Co, La and Ga. The catalysts were characterized by using XRD , H 2 -TPR, TEM , EDS, XPS , BET, ICP and TG techniques. This catalyst showed high selectivity to ethanol and excellent stability including excellent resistance to sintering and carbon deposition . It seems that the ethanol is generated in the interface between metallic Co and La 4 Ga 2 O 9 , and in the interface cobalt would be positively charged due to the interaction between Co nanoparticles and La 4 Ga 2 O 9 . The results and the related discussions indicate that Co/La 2 O 3 -doped La 4 Ga 2 O 9 catalyst is a promising catalyst for DES from syngas. Graphical abstracts.
研究领域:
催化
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化学工程
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材料科学
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产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2021
·Vol. 12
·期 4
·1144-1158
·
IF 6.119
Junke Li,Mei Li,Zhiliang Jin
An S-scheme surface heterojunction between Co3S4 and Mo2S3 was constructed successfully via a stepwise hydrothermal method. A rhombic dodecahedral cobalt-based metal–organic zeolite imidazole framework (ZIF-67) is used as the cobalt source and template to participate in the reaction process. ZIF-67 with a dodecahedral structure is first reshaped into cobalt sulfide with a hollow polyhedral structure via a one-step sulfidation reaction. And then, Mo and S species were introduced on the surface of Co3S4 to fabricate Co3S4@Mo2S3 with a hierarchical core–shell structure and S-scheme heterojunction. In comparison, the H2 evolution activity of Co3S4@Mo2S3 is about 7 and 3 times higher than those of pure Mo2S3 and Co3S4. Density functional theory (DFT) calculations were used to construct the molecular model of Co3S4 and Mo2S3, and the sample's energy band structure was also analyzed. Based on the analysis of a series of characterization results, a H2 evolution mechanism of Co3S4@Mo2S3 with a S-scheme surface heterojunction was proposed. The formation of the S-scheme surface heterojunction between Co3S4 and Mo2S3 results in a more developed channel to transfer photogenerated electrons and allows the system to retain a more effective redox potential. Besides, the Mo2S3 nanosheet's criss-cross growth on the Co3S4 surface is beneficial to the improvement of the cycle stability of the Co3S4@Mo2S3 composite. This work uses a ZIF-67 polyhedron as the template to provide a new strategy for preparing a hierarchical S-scheme surface heterojunction photocatalyst based on MOFs.
研究领域:
材料科学
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化学
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纳米技术
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光催化
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产品关联
DOI
高影响因子
Catalysts
·
2023
·Vol. 14
·期 1
·18
·
IF 3.9
Kaixuan Chen,Linsheng Xu,Yuanfeng Li,Jing Xiong,Dawei Han,Yaxiao Ma,Peng Zhang,Haoqi Guo,Yuechang Wei
Herein, we present an in-depth investigation into the enhancement of catalytic soot oxidation through cerium-doped three-dimensional ordered macroporous (3DOM) La-Co-Ni-based perovskites synthesized with the colloidal crystal template (CCT) method. The 3DOM structure significantly contributes to the accessibility and interaction efficiency between soot and catalyst. Based on the results of powder X-ray diffraction (XRD), N2adsorption-desorption measurements, scanning electron microscopy (SEM), temperature-programmed oxidation of NO (NO-TPO), temperature-programmed reduction of H2(H2-TPR), in situ infrared Fourier transform spectroscopy (In-situ DRIFTS), and temperature-programmed oxidation (TPO) reactions, the role of cerium doping in modifying the structural and catalytic properties of 3DOM perovskite-type La2−xCexCoNiO6catalysts was investigated systematically. The optimized cerium doping ratio in La2−xCexCoNiO6catalysts can improve the microenvironment for efficient soot-catalyst contact, enhancing the catalytic activity of soot oxidation. Among the catalysts, the 3DOM La0.8Ce1.2CoNiO6catalyst shows the highest catalytic activity for soot oxidation, whose T10, T50, and T90values are 306 °C, 356 °C, and 402 °C, respectively. The mechanism of the cerium doping effect for boosting soot oxidation is proposed: The doping of Ce ions can increase the surface oxygen species, which is the main active species for promoting the key step of NO oxidation to NO2in catalyzing soot oxidation. This research provides a new strategy to develop high-efficient non-noble metal catalysts for soot oxidation in pollution control and sustainable environmental practices.
研究领域:
催化
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环境科学
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材料科学
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DOI
高影响因子
危险品化学品经营许可证（带存储）