JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Tiantian Fu,Lingtao Sun,Guijun Li,Yang Xiang,Yibo Tang,Jingqi Sha,Ying Lei,Zhongping Xiong,Yujun Si,Chaozhong Guo
A nitrogen and sulfur codoped carbon-based catalyst (Fe-NS-AG-C) to oxygen reduction reaction (ORR) is prepared by pyrolyzing a precursor from iron chloride, thiourea, anhydrous glucose and carbon black. Glucose is transformed to carbon sheets with defect-rich structures which are highly active to the anchoring of nitrogen and sulfur atoms. Correspondingly, the 3.35 at% and 0.63 at% contents of nitrogen and sulfur in Fe-NS-AG-C are heavily higher than the 0.71 at% and 0.26 at% in the controlled catalyst Fe-NS-C (without glucose). The edge-oriented pyridinic N is easily formed as ORR active sites with the C-S structure. A dual mesopore-dominated microstructure is also constructed by the carbon sheets to favor the mass transfer in the reaction process. As a result, the Fe-NS-AG-C presents outstanding ORR performance with more positive half wave potential, greater limiting current density, and better methanol tolerance than the benchmark Pt/C catalyst. The Zn-air battery assembled with Fe-NS-AG-C outputs 1.48 V of open circuit voltage, 156 mW cm −2 of maximum power density, and 1.26 V of work voltage, 785 mAh g −1 Zn of specific capacity and 983 mWh g −1 Zn of specific energy density at 10 mA cm −2 of discharge current density.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Molecular Catalysis
·
2022
·
IF 5.089
Feng Li,Haiyang Zhang,Miaomiao Zhang,Wencai Peng,Lisha Yao,Yanzhao Dong,Jinli Zhang
The benchmark carbon-based catalyst, activated carbon (AC), has a low catalytic activity due to its uniform surface charge distribution and stable structure. To overcome these problems, melamine-phenol-formaldehyde (MPF) resin, which is rich in pyridinic N and pyrrolic N, multi-porous C-N materials rich with defect sites were synthesized in situ by heat treatment using silica sol as the template and phenol, melamine, and formaldehyde as the carbon and nitrogen sources. The experimental results and characterization techniques revealed that carbon materials with abundant hierarchical pores and local C-N active sites were constructed by incorporating heteroatom-containing groups. Hydrogen chloride and acetylene molecules were activated due to the high electronegativity of defective sites, and the synergistic interactions between pyridinic N and π-containing functional groups (C=C, triazine ring, etc.). The structure-performance relationship was also clarified using DFT calculations. In addition, the strong interactions between heteroatomic sites and metal species also made MPF-800 an admirable metal catalyst support. Overall, the disadvantages of acetylene hydrochlorination catalyzed by benchmark AC were resolved.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Guang-Lan Li,Tian-Ge Ma,Yu-Hui Shi,Fei Deng,Ri-Yang Huang,Yang Yan,Qing Mao,Yushan Li,Yonghou Xiao
Direct ammonia oxidation reaction (AOR) is a promising route for efficiently removing ammonia-nitrogen from wastewater. However, the sluggish kinetics and poor N 2 selectivity present significant challenges for AOR catalysts. Herein, a novel cost-effective hierarchical catalyst was constructed by selenizing NiCuO x nanorods on nickel foam support (NiSe 2 /Se-NiCuO x /NF) via the hydrothermal-calcination selenization method. The selenizing procedure radically manipulates the surface structure of NiSe 2 /Se-NiCuO x /NF, enriching it with oxygen vacancy defects and heterostructures to achieve high efficiency towards AOR. Consequently, the optimal NiSe 2 /Se-NiCuO x /NF only requires 1.50 V to achieve a current density of 65 mA cm - 2 . Furthermore, the N 2 selectivity was up to 98.18% after 5 h of electrolysis. Density functional theory (DFT) calculation elucidates that the defects and heterostructures effectively facilitates electron transfer between NiSe 2 and Cu 2 O, significantly reduces the energy barrier of the rate-determining step (RDS) of O-S mechanism. This work demonstrates the feasibility of metallic selenides as efficient electrocatalysts for AOR.
研究领域:
材料科学
·
环境科学
·
电催化
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2020
·
IF 7.489
Fenglin Zhao,Dong Xie,Wanxia Huang,Xinrui Song,Muhammad Aurang Zeb Gul Sial,Hongliang Wu,Fei Deng,Qi Zhang,Jizhao Zou,Xierong Zeng
Nickel cobalt sulfides (NCS) are regarded as potential energy storage materials due to the versatile valent states and rich electrochemical activity, but their sluggish synthesis process and inferior rate performance hinder them from large-scale application. Herein, microwave-induced strategy has been employed for efficient synthesis of honeycomb-like NCS/graphene composites, which are explored as ultrahigh rate battery-type electrodes for supercapacitors. Due to the internal heat mechanism, the synthesis time of NCS by microwave could be shortened from hours to minutes. Density functional theory was simulated to uncover the interfacial effect between NCS and graphene, and the resulted Schottky barrier is in favor of enhancing redox activity and capacity. Ultimately, the obtained defect-rich nickel cobalt sulfides/graphene with thermal treatment (NCS/G-H) could exhibit a high specific capacitance of 1186 F g −1 at 1 A g −1 and sustain 89.8% capacity even after the increase of current density over 20 times, which is much superior to bare NCS and NCS/graphene. Furthermore, the assembled NCS/G-H hybrid supercapacitor delivers supreme energy density of 46.4 Wh kg −1 , and retains outstanding long-term stability of 89.2% after 10 k cycles. These results indicate that the synthesized NCS/G-H by time-saving microwave-induced liquid process could be served as high rate materials for supercapacitors.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2022
·Vol. 28
·期 61
·e202201860
·
IF 5.02
Fan Gao,Chuanliang Li,Yangyang Ren,Baosong Li,Chenhao Lv,Xiaojing Yang,Xinghua Zhang,Zunming Lu,Xiaofei Yu,Lanlan Li
Graphical Ultrathin PdCuMo porous nanosheets with rich cavities and structural defects have been successfully prepared by a simple method. Due to the novel structures which can provide extensive active sites and the electronic interaction between Cu, Pd and Mo elements, ultrathin PdCuMo porous nanosheets display outstanding catalytic activities and stabilities. To reduce the over-dependence on Pt, Pd-based catalysts have become one of the most effective candidates for oxygen reduction reaction (ORR). In order to further accelerate the ORR kinetics and strengthen the catalytic performance of Pd catalysts, component optimization and morphology design have been adopted. Although great progress has been made, it is still difficult to obtain porous ultrathin nanosheets with excellent performance by a simple method. Here, ultrathin PdCuMo porous nanosheets (PdCuMo NSs) were successfully prepared. This structure possessed a large specific surface area with rich cavities and structural defects, significantly enhancing its ORR performance. In special, the mass activity of PdCuMo NSs was 1.46 A mg −1 at 0.90 V, which was 12.2, 8.6, and 2.7 times as high as that of Pd/C, Pt/C, and PdCuMo nanoparticles (PdCuMo NPs), respectively. In addition, it had an excellent ability to resist CO poisoning and exhibited remarkable long-term stability.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Jinqiao Li,Xuefeng Chu,Wenfu Yan,Gang Liu
Low-energy photon conversion is crucial for the efficient utilization of solar energy. To this end, a synergistic chemical structure modification method is practiced to enhance the wide-spectrum photocatalytic activity of g-C 3 N 4 (BPDCN). By altering the calcination time, we achieve an advanced small size morphology state, which significantly improves the photocarrier transport properties of g-C 3 N 4 . Furthermore, the copolymerization reaction, regulated by varying calcination temperatures, synchronously completes the doping of pyridine and the introduction of N-deficient structure in BPDCN. The modified conjugated framework of BPDCN exhibits broad spectral response capability extending up to the near-infrared region. Additionally, the construction of conjugated carbon region enhances the O 2 adsorption property of BPDCN, expanding the advanced oxidation applications in oxytetracycline degradation. The rich-defect structure of BPDCN further boosts the efficient utilization of photogenerated carriers. Consequently, the optimized BPDCN demonstrates an outstanding photocatalytic H 2 evolution (PHE) activity of 4238.1 μmol g⁻¹ h⁻¹ , approximately 63 times higher than that of pristine UCN. BPDCN also shows the significant low-energy photon utilization ability with a measurable PHE activity of 15.7 μmol g⁻¹ h⁻¹ under NIR irradiation. This work highlights the importance of chemical structure design in organic photocatalyst development.
研究领域:
材料科学
·
光催化
·
能源转换
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2024
·Vol. 107
·期 12
·8234-8245
·
IF 3.5
Lin Tang,Xuefan Zhou,Muhammad Habib,Qijun Wang,Guoliang Xue,Yan Zhang,Xi Yuan,Dou Zhang
Bismuth ferrite (BiFeO 3 )-based high-temperature piezoelectric ceramics have high Curie temperatures and excellent thermal stability; however, their applications are limited by inadequate piezoelectric performance due to large coercive fields and high leakage conduction. This study investigates the impact of MnO 2 doping on the phase transition, defect structure, domain morphology, as well as the dielectric, ferroelectric, and electrical conduction behaviors of 75BiFeO 3 –25BaTiO 3 ceramics sintered under an oxygen atmosphere. A structural transformation from distorted rhombohedral to pseudo-cubic symmetry was observed with increasing MnO 2 content, accompanied by domain fragmentation. MnO 2 doping at an appropriate level inhibited defects such as F e ′ Fe $\ {\mathrm{F}}{{{\mathrm{e^{\prime}}}}_{{\mathrm{Fe}}}}$ and V O 2 − ⋅ ⋅ $V_{{{{\mathrm{O}}}^{{\mathrm{2}} - }}}^{\centerdot \centerdot }$ . Regarding electrical properties, the reduction in rhombohedral distortion and enhancement in the pseudo-cubic phase after MnO 2 doping resulted in decreased remanent polarization and electrostrain, which could potentially hinder piezoelectric response. However, appropriate MnO 2 doping effectively reduced leakage conduction, significantly enhancing the poling efficiency of the ceramics. The maximum d 33 value of 107 pC/N and k p of 0.36 were achieved at an MnO 2 doping content of 0.1 wt.%. Excessive MnO 2 addition may generate 2 M n ′ Ti − V O 2 − ⋅ ⋅ ${\mathrm{2M}}{{{\mathrm{n^{\prime}}}}_{{\mathrm{Ti}}}}-V_{{{{\mathrm{O}}}^{{\mathrm{2}} - }}}^{\centerdot \centerdot }$ defect dipoles, as indicated by increased coercive field ( E c ) and dielectric loss. The observed increase in high-temperature resistivity with MnO 2 content is primarily attributed to reduced grain size and increased concentration of mobile defects. This study provides valuable insights for further research on the application of 75BiFeO 3 –25BaTiO 3 systems in high-temperature piezoelectric devices.
研究领域:
材料科学
·
陶瓷工程
·
电子材料
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2018
·
IF 6.14
Yuanyuan Chai,Lu Zhang,Qianqian Liu,Fengli Yang,Wei-Lin Dai
Oxidation of amines to imines under light irradiation has been widely studied in the field of heterogeneous catalysis. For the first time, we demonstrate a facile mixing calcination approach for the preparation of CeO2/g-C3N4-x as a heterojunction catalyst for the photo-oxidative coupling of benzylamine under the irradiation of a 300 W Xe arc lamp at 308 K with the air balloon. It was found that the rate constant of CeR/CN-66% was 3 times as high as that of pure CeO2 or g-C3N4. All kinds of structural characterizations suggested the formation of heterojunction between the CeO2 and g-C3N4, serving as a tunnel for the transfer of photoinduced charge, which may contribute to the improvement of photoactivity. Moreover, the Ce3+ ions and oxygen vacancy significantly promoted the adsorption and activation of substrate or molecular O2. Therefore, the efficient separation of the charges, the prolonged photoinduced electron lifetime, and the abundant defect structure (increased content of Ce3+ ions or the oxygen vacancy) were considered as the main factors for the higher photo-oxidation efficiency of the CeR/CN-66%. Another striking observation that was noticed was that the CeR/CN-66% was recycled up to five cycles under the same condition and was found to be highly efficient without any obvious decrease in the activity or selectivity due to the outstanding stability of the defect structure. Thus, highly efficient CeR/CN-x heterojunction catalyst was synthesized in this work by a simple approach for the photo-oxidation of benzylamine under mild reaction conditions, and this finding may provide wide applications in other photocatalysis areas.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2021
·
IF 7.963
Hao Li,Yi Liu,Feng Jiang,Xing Bai,Huijie Li,Di Lang,Lin Wang,Bo Pan
Cellulose and lignin derived biochars with significant differences in persistent free radicals (PFRs), oxygen-containing functional groups, and defective structure were prepared to explore the mechanism of biochar mediated persulfate (PS) activation. EPR spin trapping and quenching technique coupled with degradation experiments confirmed that the defective structures could activate PS to generate superoxide anions (O 2 •− ), which was converted to singlet oxygen ( 1 O 2 ), especially in the acidic condition. 1 O 2 dominated the degradation of ofloxacin (OFL, a fluoroquinolone antibiotic). An improved iodometric measurement was applied for direct quantification of adsorbed PS on biochar. The amounts of adsorbed PS were consistent with the degradation of OFL and the measured electric current during the reaction indicated that PS adsorption was a prerequisite for PS activation, which may be neglected in previous studies. The results of this study highlighted the key roles of defective structure and adsorption of PS on biochar for the activation of PS.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
·
2022
·
IF 7.336
Wang Zhan,Li Ma,Mengyu Gan
Constructing robust nanomaterials with surface defects is a promise way for high-efficiency methanol electrocatalysis together with minimizing poisoning of adsorbed CO. To this end, low platinum (Pt) loaded (6% wt) defects enriched PtCo alloy wrapped by carbon layers (V-Pt x Co@NC/C) enabled via facile pyrolysis . In the pyrolysis process, the metal salts are subjected to alloying and dealloying process under high temperature annealing combined with etching treatment to construct defects and boundaries enriched PtCo alloy. These defects and boundaries enriched structure can provide abundant active edge atoms with low coordination numbers as well as are beneficial for more exposed active sites of Pt, rendering the large electrochemical surface areas and changing the reaction properties for intermediates of methanol oxidation . In-situ Fourier transform infrared spectroscopy shows that the catalyst follows direct HCOO − pathway with CO-free dominant. Thus, presenting excellent mass activity (1328 mA mg −1 Pt ) in acid medium. Moreover, benefiting from the protection of carbon layers, possible dissolution of metallic can be diminished. Therefore, the catalyst delivers superhigh stability and can maintain 80% of mass activity after 1000 cycles. This work poses a new avenue for the design of cost-effective catalyst.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2022
·
IF 8.129
Jing Liu,Yinzhao Jia,Sen Wang,Jinchuan Fan,Wei Huang
The impact of nanomaterial morphology on the structures of catalysts has drawn intense interest. Based on previous work, we discovered that ZnO plays an essential role in the ethanol production . In this research, we discussed the impact of ZnO with different morphology (rod-like, granular-like and flower-like) on the performance of CuZnAl slurry catalysts for the ethanol production. The catalytic performance was evaluated at H 2 /CO = 2, 250 °C and 4.0 MPa, and the catalyst structures were tested by XPS, in situ DRIFT and so on. The results show that CuZnAl catalysts prepared with rod-like and granular-like ZnO show the better selectivity of methanol and DME, which is assigned to the highly dispersion of Cu species and more quantity of acidic sites, respectively. CuZnAl catalyst prepared with flower-like ZnO possesses the higher total alcohol selectivity (45.0%) and the highest ethanol proportions in total alcohol (50.0%). Flower-like ZnO that exposed more polar (002) facets results in more surface defect structures (oxygen vacancy, Zn (2-δ) ) and high ratio of Cu 0 /Cu + in this catalyst, all of which are related to the formation of ethanol.
研究领域:
催化化学
·
纳米材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of the American Chemical Society
·
2023
·
IF 15
Zhi-Zheng Wu,Xiao-Long Zhang,Peng-Peng Yang,Zhuang-Zhuang Niu,Fei-Yue Gao,Yu-Cai Zhang,Li-Ping Chi,Shu-Ping Sun,Jing-Wen DuanMu,Pu-Gan Lu,Ye-Cheng Li,Min-Rui Gao
Carbon–carbon coupling electrochemistry on a conventional copper (Cu) catalyst still undergoes low selectivity among many different multicarbon (C2+) chemicals, posing a grand challenge to achieve a single C2+ product. Here, we demonstrate a laser irradiation synthesis of a gerhardtite mineral, Cu2(OH)3NO3, as a catalyst precursor to make a Cu catalyst with abundant stacking faults under reducing conditions. Such structural perturbation modulates electronic microenvironments of Cu, leading to improved d-electron back-donation to the antibonding orbital of *CO intermediates and thus strengthening *CO adsorption. With increased *CO coverage on the defect-rich Cu, we report an acetate selectivity of 56 ± 2% (compared to 31 ± 1% for conventional Cu) and a partial current density of 222 ± 7 mA per square centimeter in CO electroreduction. When run at 400 mA per square centimeter for 40 h in a flow reactor, this catalyst produces 68.3 mmol of acetate throughout. This work highlights the value of a Cu-containing mineral phase in accessing suitable structures for improved selectivity to a single desired C2+ product.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）