SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Quanzhi Zhang,Tianlin Zhou,Xinchun Ye,Zhi-Xia Zhang,Shaolin Wu,Dezhi Chen
Persulfate-based advanced oxidation process dominated by singlet oxygen ( 1 O 2 ) shows potential for targeted degradation of organic pollutants but the regulation of 1 O 2 generation is still challenging. In this study, N-doped carbon polyhedron-modified Co@N-doped carbon nanotube (NCP/Co@NCNT) were successfully fabricated. The as-obtained NCP/Co@NCNT demonstrated a much enhanced 1 O 2 production in activating peroxymonosulfate (PMS) because of the nanoconfinement effect of metallic Co nanoparticles encapsulated in NCNT, which was further confirmed by density functional theory calculations. The NCP/Co@NCNT/PMS system has excellent catalytic performance and is capable of removing 97 % of carbamazepine (CBZ) in 55 min (Catalyst: 0.1 g/L, CBZ: 20 mg/L, PMS: 0.5 g/L). Quantitative structure–activity relationship (QSAR) analysis uncovered a positive correlation between the oxidation kinetics of organic pollutants and their E HOMO . Specifically, pollutants with higher E HOMO are more easily oxidized in the 1 O 2 -dominated NCP/Co@NCNT/PMS system. Furthermore, the generated intermediates exhibited low toxicity in the system with 1 O 2 as the primary active species. This study offers an effective approach to prepare catalysts for the selective elimination of organic micropollutants in complex water environments.
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART B-ENGINEERING
·
2023
·
IF 13.1
Xiang Zhang,Zheng Xiang,Kai Yao,Xiao Wang,Hao jie Jiang,Jing li Wang,Wei Lu
Heterointerface engineering is now recognized as a powerful strategy to optimize the microwave absorption performance of dielectric materials through composition adjustment and structural design. Herein, a hydrangea-like N-doped Carbon/MoO 2 @SnS 2 (NC/MoO 2 @SnS 2 ) composite was successfully prepared by high-temperature pyrolysis and oil bath treatment. The surface of each NC/MoO 2 microsphere was vertically covered with interconnected SnS 2 nanosheets , forming a porous core-shell morphology. We found that the number of heterojunctions and the proportion of high-lossy phases played a decisive role in optimizing the electromagnetic parameters . By regulating the content of dielectric phases, the optimized NC/MoO 2 @SnS 2 (S3 sample) displayed a minimum reflection loss (RL min ) of −75.0 dB at an ultrathin thickness of 1.41 mm and a wide EAB of 4.2 GHz at 1.53 mm. The enhanced microwave absorption was mainly ascribed to multiple polarization relaxation, multi-interface reflection and good impedance matching characteristics produced by this semiconductor/carbon heterostructure with dual Schottky barriers . Therefore, this work provided a feasible strategy for making full use of heterointerface engineering to design ternary semiconductor/carbon heterostructures as high-performance dielectric MAMs.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
高影响因子
Carbon Letters
·
2025
·
IF 5.8
Hu Chaoshuai,Liu Yuanxin,Zhang Jian,Zhu Yaming,Yin Xitao,Zhao Xuefei
Using durian shell as a carbon source and triethanolamine as a nitrogen dopant, nitrogen-doped carbon dots (N-CDs) were prepared via the hydrothermal method. First, by exploring different reaction times, reaction temperatures, and carbon source/dopant ratios to synthesize nitrogen-doped carbon dots, it is concluded that the best process conditions are 200 ℃, reaction time being 15h, and the dopant addition amount being 2mL. Structure and characteristics of the synthesized CDs were analyzed using X-ray photoelectron spectroscopy, Fourier-transform infrared, fluorescence (FL), ultraviolet–visible absorption, and Raman spectra. The N-CDs showed blue FL with a quantum efficiency of 4.28%. The FL characteristics of the N-CDs were utilized for ion detection, which demonstrated that \({\text{MnO}}_{4}^{ - }\) and \({\text{Cr}}_{{2}} {\text{O}}_{7}^{2 - }\) ions caused distinct FL quenching through static quenching, while other ions had no significant quenching effect. The detection limits for \({\text{MnO}}_{4}^{ - }\) and \({\text{Cr}}_{{2}} {\text{O}}_{7}^{2 - }\) were 37.5 and 46.2 nM, respectively. The N-CDs were subsequently employed to detect these ions in actual water samples, producing satisfactory results. Therefore, the preparation of N-CDs using durian shell as raw material and its application in practical detection work have good application feedback, which not only provides a new way for the reuse of fruit and vegetable wastes but also provides a new detection means for environmental monitoring pollutants.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Frontiers of Chemical Science and Engineering
·
2021
·Vol. 15
·期 5
·1185-1196
·
IF 4.204
Liu Wanyue,Liu Xiaoqin,Chang Jinming,Jiang Feng,Pang Shishi,Gao Hejun,Liao Yunwen,Yu Sheng
The magnetic nitrogen-doped carbon (MNC) was prepared from polypyrrole by a simple high temperature calcination process in this paper. The structure and properties of MNC were analyzed by scanning electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, Brunner-Emmet-Teller, vibrating sample magnetometer, and X-ray photoelectron spectroscopy. The capacity of MNC to adsorb Cr(VI) and Pb(II) was evaluated. The effects of the initial pH, dosage, concentration and temperature on the adsorption capacity of MNC were measured. MNC had a large specific surface area and a special porous structure. Its nitrogen and carbon sources were rich, and the ratio of carbon to nitrogen was fixed. The maximum Cr(VI)-adsorption capacity and maximum Pb(II) adsorption capacity of MNC could reach 456.63 and 507.13 mg·g −1 at 318 K, respectively. The pseudo-second-order model was used to describe the adsorption kinetics of MNC, and the Freundlich model was employed to discuss its isotherms. The adsorption process was affected by the electrostatic force, the reducing reaction, pores and chelation. The results of this study suggest that MNC is a material with superior performance, and is very easily regenerated, reused, and separated in the adsorption process.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Hao Song,Siguang Guo,Xuming Zhang,Yixuan Yang,Biao Gao,Yuancheng Pi,Chaoran Pi,Paul K. Chu,Kaifu Huo
The development of high active and cost-effective transition metal based catalysts as alternatives to Pt-based electrocatalysts for pH-universal hydrogen evolution reaction (HER) is highly desirable. Herein, we proposed a novel strategy to construct Mo 2 N uniformly embedded Mo 2 C nanobelt arrays electrocatalyst on N doped carbon framework (Mo 2 N-Mo 2 C/NC NBAs) by nitridation of MoO x /C hybrid precursors and subsequent annealing. The effect of N content towards the composition ratio of Mo 2 N to Mo 2 C and the structural evolution were studied. The in-situ formed Mo 2 N reduces the sintering of Mo 2 C phase and creates amounts of compact Mo 2 N-Mo 2 C interfaces and mesopores. Because of these high active interfaces, mesopores structure and self-supported architecture, the resultant Mo 2 N-Mo 2 C/NC catalyst exhibits remarkable HER performance and durability over a wide pH range, as exemplified by a small overpotentials of 75, 93, and 114 mV at 10 mA cm −2 , and Tafel slopes of 43, 58, and 62 mV dec −1 in the alkaline, neutral and acidic media. The results reveal a new avenue to design highly efficient electrocatalysts with tailored hetero/microstructures, which could be extended to fabricate other high-performance electrocatalyst and electrode materials for electrochemical energy conversion.
研究领域:
材料科学
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电化学
·
能源转换
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Xin Guo,Hao Zhang,Ke Chen,Xiaodie Li,Xuran Yang,Chengming Xiao,Yiyuan Yao,Minjie Song,Junwen Qi,Yujun Zhou,Yue Yang,Zhigao Zhu,Jiansheng Li
Rational design of high-performance electrode materials is crucial for enhancing desalination performance of capacitive deionization (CDI). Here, ultrathin nitrogen-doped carbon/Ti 3 C 2 T x -TiN (NC/MX-TiN) heterostructure was developed by pyrolyzing zeolite imidazolate framework-8 (ZIF-8) nanoparticles sandwiched MXene (ZSM), which were formed by assembling ultrafine ZIF-8 nanoparticles with size of 20 nm on both sides of MXene nanosheets. The introduction of ultrasmall ZIF-8 particles allowed for in situ nitridation of the MXene during pyrolysis, forming consecutive TiN layers tightly connected to the internal MXene. The two-dimensional (2D) heterostructure exhibited remarkable properties, including high specific surface area and excellent conductivity. Additionally, the resulting TiN demonstrated exceptional redox capability, which significantly enhanced the performance of CDI and ensured cycling stability. Benefiting from these advantages, the NC/MX-TiN exhibited a maximum adsorption capacity of 45.6 mg g −1 and a steady cycling performance in oxygenated saline water over 50 cycles. This work explores the rational design and construction of MXene-based 2D heterostructure and broadens new horizons for the development of novel CDI electrode materials.
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanomaterials
·
2021
·Vol. 11
·期 2
·261
·
IF 5.076
Wendi Zhang,Xiaoming Liu,Man Gao,Hong Shang,Xuanhe Liu
The oxygen reduction reaction (ORR) is a crucial step in fuel cells and metal-air batteries. It is necessary to expand the range of efficient non-precious ORR electrocatalysts on account of the low abundance and high cost of Pt/C catalysts. Herein, we synthesized crystalline cobalt-embedded N-doped carbon nanotubes (Co@CNTs-T) via facile carbonization of Co/Zn metal-organic frameworks (MOFs) with dicyandiamide at different temperatures (t = 600, 700, 800, 900 °C). Co@CNTs- 800 possessed excellent ORR activities in alkaline electrolytes with a half wave potential of 0.846 V vs. RHE (Reversible Hydrogen Electrode), which was comparable to Pt/C. This three-dimensional network, formed by Co@CNTs-T, facilitated electron migration and ion diffusion during the ORR process. The carbon shell surrounding the Co nanoparticles resulted in Co@CNTs-800 being stable as an electrocatalyst. This work provides a new strategy to design efficient and low-cost oxygen catalysts.Keywords:metal-organic frameworks;N-doped carbon;oxygen reduction reaction
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Xin Zhang,Zhuanghe Ren,Yunhao Lu,Jianhua Yao,Mingxia Gao,Yongfeng Liu,Hongge Pan
Herein, we synthesize successfully ultrafine TiN nanoparticles (<3 nm in size) embedded in N-doped carbon nanorods (nano-TiN@N–C) by a facile one-step calcination process. The prepared nano-TiN@N–C exhibits superior catalytic activity for hydrogen storage in NaAlH4. Adding 7 wt % nano-TiN@N–C induces more than 100 °C reduction in the onset dehydrogenation temperature of NaAlH4. Approximately 4.9 wt % H2 is rapidly released from the 7 wt % nano-TiN@N–C-containing NaAlH4 at 140 °C within 60 min, and the dehydrogenation product is completely hydrogenated at 100 °C within 15 min under 100 bar of hydrogen, exhibiting significantly improved desorption/absorption kinetics. No capacity loss is observed for the nano-TiN@N–C-containing sample within 25 de-/hydrogenation cycles because nano-TiN functions as an active catalyst instead of a precursor. A severe structural distortion with extended bond lengths and reduced bond strengths for Al–H bonding when the [AlH4]− group adsorbs on the TiN cluster is demonstrated for the first time by density functional theory calculations, which well-explains the reduced de-/hydrogenation temperatures of the nano-TiN@N–C-containing NaAlH4. These findings provide new insights into designing and synthesizing high-performance catalysts for hydrogen storage in complex hydrides.
研究领域:
材料科学
·
能源化学
·
理论计算
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Biomass Conversion and Biorefinery
·
2022
·
IF 4.05
Gao De,Han Feng,Waterhouse Geoffrey I. N.,Li Yan,Zhang Lili
A series of FeTPP-N/C-X catalysts were successfully prepared by adsorption of Fe tetraphenylporphine (FeTPP) onto a porous nitrogen-doped carbon (N/C) support using an ultrasonication method. The FeTPP-N/C catalysts were then used for the preparation of 5-hydroxymethyl-2-furan acid (HMFCA) by catalytic oxidation of 5-hydroxymethylfurfural (HMF) at 80 °C. The effects of reaction temperature, NaOH dosage, reaction time, and oxygen pressure on HMF conversion and HMFCA yield were systematically investigated. Under optimized testing conditions, a FeTPP-N/C-1 catalyst prepared using equal masses of FeTPP and N/C delivered a HMF conversion in water of 92.4%, with a selectivity to HMFCA of 97.2% over 6 h at an oxygen pressure of 1.0 MPa. Further, the catalyst showed good stability in five consecutive HMF oxidation tests. Based on the catalytic tests, and detailed catalyst characterization studies before and after reaction, a probable reaction mechanism was proposed for the selective oxidation of HMF to HMFCA by the FeTPP-N/C catalysts. Graphical Abstract
A series of FeTPP-N/C
catalysts were successfully prepared by the adsorption of iron
tetraphenylporphine (FeTPP) onto a porous nitrogen-doped carbon (N/C) support
using an ultrasonication method. The FeTPP-N/C catalysts were then used for the
catalytic aerobic oxidation of HMF to HMFCA. Under the optimized reaction conditions (temperature
80 °C, reaction time 6 h, O 2 pressure 1 MPa), a high HMF conversion
of 92.4% and a remarkable HMFCA selectivity of 97.2% were obtained, suggesting
that the developed noble-metal free catalyst has excellent promise for the
synthesis of valuable HMFCA from HMF.
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
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Xiangyu Jia,Kai Yuan,Guofu Wang,Shanhui Zhu,Mei Dong,Jiamin Wang,Xiaoming Li,Weibin Fan
Selective reduction of 5-hydroxymethylfurfural (HMF) to valuable 2,5-bis(hydroxymethyl)tetrahydrofuran (BHMTHF) remains a significant challenge under mild conditions. The synergistic effect between metal single atoms (SAs) and nanoparticles (NPs) can greatly enhance catalytic activity. Here, a high-performance Pd SAs catalyst supported on N-doped carbon (PdSAs/NC) was developed from Pd@UiO-66-NH 2 . It was found that partial Pd SAs were spontaneously restructured into Pd NPs during the reaction. Our catalyst exhibited 100 % conversion of HMF and 98 % selectivity towards BHMTHF at temperature as low as 0 °C. In situ FTIR spectra results and density functional theory calculations indicate that Pd SAs contribute to the C = O activation, while Pd NPs facilitated the H 2 dissociation into H* atoms, resulting in synergistic catalytic activity between Pd SAs and Pd NPs.
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
·
2020
·
IF 6.551
Songrong Li,Wenli Huang,Peizhen Yang,Zhendong Li,Baiqin Xia,Mingjie Li,Cheng Xue,Dongfang Liu
Nitrogen-doped carbon intercalated molybdenum disulfide nanohybrid (NC-MoS 2 ) with well-interconnected nanosheets was successfully fabricated using a one-pot hydrothermal method and applied as a novel adsorbent to remove tetracycline (TC) from aqueous solutions. Series material characterizations indicated that the intercalation of nitrogen-doped carbon into MoS 2 nanosheets could produce widened interlayer spacing, enlarge the specific surface area and create more extensive functional groups. The adsorption kinetics and isotherms investigations revealed that the pseudo-second-order model and Langmuir isotherm model could fit well the TC adsorption behavior of NC-MoS 2 . Particularly, NC-MoS 2 possessed a high maximum adsorption capacity (1128.4 mg/g) that was approximately 2.8 times that of pristine MoS 2 (409.84 mg/g) at 308 K and pH = 6.0 ± 0.1. Furthermore, the relevant thermodynamic parameters indicated that the adsorption process was spontaneous and endothermic. The adsorption process was dependent on multiple interactions including hydrophobicity , π-π stacking interaction and hydrogen bond . These findings demonstrated that NC-MoS 2 had potential applications for treating TC-containing water and broadened the application of metal sulfides in the environmental field.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
GREEN CHEMISTRY
·
2021
·Vol. 23
·期 18
·7065-7073
·
IF 10.182
Liang Jiang,Guangyue Xu,Yao Fu
The conversion of levulinic acid (LA) to γ-valerolactone (GVL) is one of the most important reactions from biomass-derived platform chemicals to value-added chemicals. In this work, nitrogen-doped carbon was introduced into a Ni/Al2O3 catalyst and was employed for the hydrogenation of LA to GVL with a full conversion and equivalent yield under mild conditions, at as low as ambient hydrogen pressure and 130 °C for 6 h. The doping of nitrogen introduced NiNx species and the imperfection of modified nitrogen-doped carbon were beneficial for the selective hydrogenation of carbonyl groups. This catalyst showed excellent activity and selectivity in various solvents and could be recycled for at least 6 runs with little deactivation. In addition to LA, various substrates with both carbonyl and carboxyl groups could also be selectively hydrogenated to the corresponding lactones. This study offers both theoretical foundation and practical instructions for the high-efficiency conversion of LA to GVL over non-noble metal catalysts under mild conditions, especially ambient H2 pressure.
研究领域:
催化化学
·
生物质能转化
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）