SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Yijie Feng,Wenjiao Sang,Zhiyi Deng,Shiyang Zhang,Cuihua Li
Co-N-C@SiO 2 with Co, N doped carbon as core and SiO 2 as shell was successfully synthesized by template method, and SiO 2 shell was about 43 wt%. Impressively, the SiO 2 shell increased the active sites of the core in Co-N-C@SiO 2 preparation, and reduced the loss of active sites during use. Co-N-C@SiO 2 /PMS was a 1 O 2 dominated non-radical reaction, which was less interfered by solution pH and water constituents. In addition, Co-N-C@SiO 2 possessed better cycling performance compared with Co-N-C. Finally, the possible SMX degradation pathways were presented based on the identified intermediate products.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Shiping Shao,Shuzhi Xing,Ke Bi,Tingting Zhao,Hao Wang,Yunxiang Tang,Jiurong Liu,Fenglong Wang
The fabrication of dielectric/magnetic multicomponent hybrids represents a promising strategy for achieving advanced electromagnetic wave (EMW) absorption performances. However, it also poses a significant challenge due to the difficulty in fully utilizing the properties of each component. Here, in this work, metal–organic frameworks (MOFs) derived Co-N-C species were combined with graphene oxide/polyamide acid and then freeze-dried and annealed to produce PI/rGO/CNC aerogels. These aerogels exhibit outstanding EMW absorption properties owing to their multiple heterogeneous interfaces and synergetic electromagnetic losses while retaining satisfying mechanical properties and lightweight features of PI/rGO aerogels. In particular, PI/rGO/CNC-1 aerogel shows the optimal EMW attenuation performance with a minimal reflection loss (RL min ) value of –75 dB, and its maximal effective absorption bandwidth (EAB max ) is as broad as 7.28 GHz. Moreover, the lightweight nature, elastic feature, structural stability, thermal insulation and hydrophobicity of the PI/rGO/CNC aerogels ensure that they have vast application prospects as advanced EMW absorption materials in complicated environment.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2019
·
IF 4.182
Junmei Luo,Shufeng Bo,Qingda An,Zuoyi Xiao,Haisong Wang,Weijie Cai,Shangru Zhai,Zhongcheng Li
Rational design of ordered catalytic composites with high performance and facile preparation method for environmental remediation still remains a tremendous challenge. For this vision, ordered composites with confined cobalt intercalated N/C layers (Co–N/C) were successfully prepared via carbonizing a mixture of cobalt species, histidine (His) and zirconium-containing SBA-15 (ZS) utilizing a simple non-solvent method. Taking the confinement effect and inherent hydrophilic groups (Si–OH) of mesoporous silica as the foothold, the strong Co 2+ /N or Co 2+ /O coordination (Co 2+ (–COO - or –NH 2 ) 2 and Co 2+ (–O - ) 2 ) and silica/His or His/His adhesive/cohesive interactions endowed the Co-based catalyst with optimal interfacial properties , cycling stability and magnetic separability for degradation of several pollutants (phenol, antibiotics and dyes). The degradation efficiency of Co@NC-ZS-700 for bisphenol A was superior to Co-ZS-700, NC-ZS-700 and Co@NC-SBA-700 due to the flaky structure with confined Co–N/C layers, which could achieve 95.0% within 20 min. In addition, the catalyst could still degrade more than 84.4% bisphenol A after five consecutive reactions. Based on the characterization analysis, tested active species (SO 4 •– , • OH and 1 O 2 ) and degradation products, double-process activation mechanism and degradation pathways were plausibly proposed (radical and non-radical processes). Additionally, various influencing factors, including carbonization temperature, amount of cobalt species, peroxymonosulfate (PMS)/catalyst dosage, pH value, coexisting ions and real water environment, were also systematically studied. This work might pave a feasible way for contaminant treatment utilizing ordered mesoporous silica composites with diffusion promoted channels involved under aqueous systems.
研究领域:
环境科学
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催化化学
✓ 已验证
DOI
高影响因子
NANOTECHNOLOGY
·
2021
·Vol. 33
·期 10
·105601
·
IF 3.874
Li Lin,Xing Du,Junjie Wang,Hui Chen,Xuan He,Wei Fang,Yang Li,Zhen Chen,Lei Zhao
Two-dimensional (2D) cobalt zeolitic imidazolate frameworks (ZIF-67) have attracted significant research interests to synthesize cobalt and nitrogen co-doped carbon-based (Co–N–C) catalyst for oxygen reduction reaction (ORR). However, most of the current synthetic approaches of 2D ZIF-67 are energy-intensive, environmentally hazardous and low-yield. Herein, a feasible and efficient 'morphology-retaining method via a high-pressure vapor-solid reaction' are reported to synthesize 2D ZIF-67 nanosheets by using 2D cobalt carbonate hydroxide template. In the strategy, the high-pressure vapor caused by sublimation of 2-Melm and the pores formed from effusion of CO2 during transformation ensure the complete transformation from 2D template to 2D ZIF-67. The corresponding 2D Co–N–C catalyst exhibits comparable ORR electrocatalytic activity and better stability than Pt/C in alkaline media. The present method is expected to offer a feasible and universal way to efficiently synthesize 2D M–N–C catalysts.
研究领域:
材料科学
·
电化学
·
催化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Dege Xili,Qian Zhou,Lijuan Zhang
Non-precious metal nitrogen-carbon composites (M-N-C) derived from ZIFs are an excellent non-precious metal catalyst for use in energy conversion and storage devices such as fuel cells and metal-air batteries. Herein ZIF-67 precursor with good dispersion, perfect crystal structure and size of below 270 nm was synthesized by consuming low amount of 2-methylimidazole ligand using a mixture of ethanol (EA) and methanol (MT) as the reaction medium. Compared with the traditional method of reducing the size of ZIF-67 by increasing the amount of ligands in methanol, this method avoids the waste of raw materials and saves the cost. The Co-N-C-MT/EA catalysts derived from ZIF-67 exhibits good ORR activity in alkaline media (0.1 M KOH) with a half-wave potential of 0.81 V vs RHE. After 5000 cycles, the initial potential and half-wave potential basically remain no change, showing excellent long-term stability. And remarkable methanol resistance is also displayed comparing with commercial Pt/C. The present experimental result shows that the improved synthesis method of ZIF-67 precursors has far-reaching implications for the field of catalyst research.
研究领域:
材料科学
·
催化化学
·
能源转换与存储
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Yiting Bu,Jiaxi Liu,Dan Cai,Pengru Huang,Sheng Wei,Xiaoshuang Luo,Zhaoyu Liu,Fen Xu,Lixian Sun,Xueying Wei
NaBH 4 (10.8 wt% theoretical hydrogen storage capacity) is an ideal hydrogen carrier, but its hydrolysis reaction at room temperature requires high-efficiency catalysts for activation and acceleration. Structured catalysts can effectively inhibit metal particle agglomeration . However, metal particles fall off the surface of the support during testing. Therefore, we report a magnetic recyclable hollow shell material H-Co/N/C-Ru@C-T. The dual protection of carbonized ZIF-67 as a framework and surface-coated carbon film makes it show good catalytic activity and durability in NaBH 4 hydrolysis reaction. The hydrogen generation rate (HGR) is as high as 9815.82 mL H2 min −1 g −1 , and the activation energy ( E a ) is reduced to 26.9 kJ mol −1 . Moreover, it retains 81.3% of its initial catalytic activity even after 25 hydrolysis cycles. Through a series of characterization, such as electron scanning spectroscopy and inductively coupled plasma atomic emission, the improvement effect of using hollow Co/N/C as framework and coating carbon film on surface on the catalytic activity and durability of H-Co/N/C-Ru@C-650 is systematically revealed. We believe this work is of unusual significance on exploring novel hydrogen storage material catalysts, especially providing opportunities for the improvement of catalytic activity and durability of catalysts.
研究领域:
材料科学
·
催化化学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Yang Chen,Tianyi Ma,Ruiqing Ke,Mengyu Lu,Jiaxing An,Yijia Wang,Kunlun Huang,Yunbo Luo,Jin-Cheng Li,Nan Cheng
The consumption of Se-rich foods is a highly effective means of augmenting a person’s intake of Se, which plays a critical role in human health; however, excessive Se consumption can be toxic. The determination of Se levels is therefore of paramount importance to ensure the safety of both the production and consumption of selenium-rich foods. In this study, a rapid and user-friendly method is developed for the analysis of selenium-rich foods wherein the detection process is similar to watching three-dimensional movies in a theater. A portable 3D-printed colorimetric device called the Detection THEATER ( T ime-saving, H igh-sensitive, E asy, A ccurate, T elling, E conomical, and R apid) is first constructed for the rapid and visually accessible colorimetric analysis of samples in nonlaboratory settings. Subsequently, the Co-N-C nanozyme is doped with Pt to produce a Pt-Co-N-C nanozyme with superior peroxidase-like activity, which serves as the viewing glasses for signal amplification in the Detection THEATER. The Detection THEATER exhibits excellent sensitivity and accuracy, including a linear range of 0.5–1.2 μg/mL and a low detection limit of 0.026 μg/mL. The pretreatment of food samples is also optimized and simplified, thereby reducing processing times three-fold and enhancing accessibility and usability. The Pt-Co-N-C nanozyme-based Detection THEATER, demonstrated outstanding specificity and practicality, opening up a new avenue for the analysis of selenium-rich foods.
研究领域:
分析化学
·
食品科学
·
纳米技术
·
公共卫生
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2022
·
IF 11.307
Dangcheng Su,Yuanhua Xiao,Yingliang Liu,Shengang Xu,Shaoming Fang,Shaokui Cao,Xuezhao Wang
2D MXenes (transition metal carbides, Ti 3 C 2 T x ) with large surface area and metallic conductivity are widely used as supporters in catalysts. Unfortunately, the single MXene sheets would deteriorate in the presence of oxygen and water, which is almost the same as the environment of oxygen reduction reaction (ORR). Herein, an “armor” was constructed to encapsulate the oxidizable MXene by a confined in-situ oxidative polymerization strategy, employing the electrostatic interaction between the exfoliated MXene sheets (negatively charged) and oxidant (Fe 3+ , positively charged). The ultra-dispersed binary Fe 3 N and Co sits coupled with the large surface area MXene supporter synergy to endow more exposed active sites, meanwhile, the density functional theory (DFT) studies reveal that a moderate binding strength between the intermediates and the binary active sites was effectively modulated to enhance the ORR performance. The synthesized Fe 3 N/Co–N–C@MXene exhibits an impressive half-wave potential (E 1/2 , 0.871V) and a lower Tafel slope of 52.56 mV dec −1 than that of Pt–C-20% (74.89 mV dec −1 ). The Fe 3 N/Co–N–C@MXene based ZAB exhibits a four times higher peak power density (189.16 mW cm −2 ) than the Pt–C-20% based ZABs and superior cycle stability within 320 h. Furthermore, the assembled flexible ZABs shows high flexibility and stability in different bending scenarios.
研究领域:
材料科学
·
电化学
·
纳米催化
·
能源存储与转换
·
功能材料
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Rui Wang,Hongcen Yang,Niandi Lu,Shulai Lei,Dali Jia,Zhixia Wang,Zhenhua Liu,Xiaogang Wu,Hanzhen Zheng,Salamat Ali,Fei Ma,Shanglong Peng
Developing highly active and robust non-noble metal bifunctional electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is of dominant significance for global applications in rechargeable Metal-air Batteries. Fine-tuning the exposed active sites is a competent way to improve their performance. Herein, the NaCl template-assisted strategy for rationally designing a three-dimensional cellular structured nitrogen-doped carbon matrix integrated with nano-scaled Co species has been developed. The resulting electrocatalyst (3D Co/N-C) exhibits a positive half-wave potential of 0.84 V (vs RHE) in ORR, and a low potential of 1.56 V (vs RHE) at 10 mA cm −2 during OER process. Moreover, 3D Co/N-C based Zn-air Batteries (ZABs) exhibit excellent battery performance, especially remarkable power density. The poisoning experiments and DFT calculations identify active sites as pyridinic N and Co during ORR and OER processes, respectively. This work provides a general and easy-to-perform tactic to design bifunctional catalysts, thus helps precisely modulate effective components for ZABs.
研究领域:
电化学
·
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Yi Gao,Xinyang Tan,Guanlong Wang,Xiaoli Dong,Xiufang Zhang
The water treatment performance of membrane filtration is usually restricted via the paradox between permeability and selectivity. Herein, the nitrogen doped porous carbon supported Co catalysts (CoNPC), serving as both porous filler and peroxymonosulfate (PMS) activator, were firstly filled into polyvinylidene fluoride (PVDF) matrix to construct a novel mixed matrix catalytic membrane (CoNPC@PVDF) for enhanced water purification. Owing to the robust binding between CoNPC and PVDF, a high loading (50 wt%) and even dispersion of CoNPC were realized in CoNPC@PVDF, and its permeability and selectivity were both improved with the increase of CoNPC content. The optimum CoNPC@PVDF with PMS activation assistance (FCP) exhibited effective phenol removal at short retention time (1.5 s) and high permeability (256.6 L m −2 h −1 bar −1 ). The performance of CoNPC@PVDF FCP was 2.9 and 2.5 times higher than that of filtration alone and PMS activation alone, respectively, and even dramatically outweighed the reported catalytic membranes and heterogeneous catalysts. The outstanding performance of CoNPC@PVDF catalytic membrane was mainly attributed to its thin membrane structure and high filling degree of CoNPC, resulting in ultrahigh mass transfer rate (1.8 × 10 −4 m s −1 ) and more exposed active sites for enhanced PMS activation into radicals (mainly •OH and SO 4 •− ) towards pollutant removal.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2021
·
IF 10.588
Huiwang Dai,Wenjun Zhou,Wei Wang,Zhiqi Liu
In this study, three Co/N-C catalysts were prepared by pyrolysis of bimetallic zeolitic imidazole frameworks with different Co/Zn ratio, and the critical active Co species in peroxymonosulfate (PMS) activation was investigated. The three catalysts had distinct cobalt species but similar N configuration and graphitization degree. The Co species were distributed as single atoms (Co SAs) at a Co/Zn molar ratio of 1:8, while Co nanoclusters (Co NCs) and Co nanoparticles (NPs) would be formed with further increase in Co content. The degradation efficiency of BPA did not show correlation with the increasing of Co content in catalyst. Based on the catalytic performance comparison and reactive species detection, Co SAs was identified as active sites, which could interact with PMS to generate 1 O 2 via path of PMS→HOO*→O*→ 1 O 2 . However, the role of NCs and NPs in directly activating PMS was negligible. In addition, the increase of Co content in Co/N-C catalyst would result in mass cobalt leaching, which enhanced the BPA degradation via homogeneous catalytic reactions with Co IV as reactive species. It is an effective way to design the Co/N-C catalyst with high catalytic activity and stability via regulating the formation of Co SAs.
研究领域:
环境化学
·
催化
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Catalysis
·
2021
·
IF 13.084
Lipeng Wu,Bin Li,Yang Li,Xiaobin Fan,Fengbao Zhang,Guoliang Zhang,Qing Xia,Wenchao Peng
Herein, a series of Co@N–C materials are synthesized using nitrates (LiNO3, NaNO3, and KNO3) as templates to control the preferential growth of the cobalt (200) facet. Co@N–C–X (X = LiNO3, NaNO3, and KNO3) exhibit excellent activities and long-term stabilities for Fenton-like degradation of bisphenol A (BPA) with peroxymonosulfate (PMS) as an oxidant. The texture coefficient (TC) is used to investigate the relationship between the Co facets and their catalytic activities, and a linear relation is built between the TC of Co(200) and the reaction rate constant (k). Co(200) is therefore the most active facet for PMS activation, while nitrates can promote the preferential growth of the Co(200) facet. Moreover, the Co(200) facet is more stable against leaching and can achieve more quick transformation between Co2+/Co3+. Quenching tests, electron paramagnetic resonance spectra, and electrochemical tests show that singlet oxygen (1O2) plays the dominant role for BPA degradation. Density functional theory verifies that Co nanoparticles coated with a graphitic nitrogen-doped carbon layer have the best activity for PMS activation. This work first proposes the strategy of using nitrates to control the preferential growth of Co facets and reveals the relationship between the TC value and k, thus attracting great interest in the environmental field.
研究领域:
环境科学
·
催化
·
材料科学
✓ 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）