Journal of Physical Chemistry C
·
2019
·
IF 4.309
Xueyang Song,Li Huang,Wenxue He,Chengyong Liu,Fengchun Hu,Yong Jiang,Zhihu Sun,Shiqiang Wei
Electronic metal–support interactions (EMSIs) have opened a new way to tailor the electronic and catalytic properties of supported catalysts. Herein, we demonstrate the EMSIs between Pt nanoparticles and Co(OH)2 flakes grown on SiO2 and show its beneficial effect on enhancing the CO oxidation activity. The EMSI characteristics of the Pt–Co(OH)2/SiO2 catalyst are identified by in situ X-ray absorption fine structure (XAFS) spectroscopy, in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), and transmission electron microscopy. Quantitative XAFS analysis reveals the presence of metallic-like Pt–Co bonds. The formation of Pt–Co intermetallic bonds allows for electron donation form Co to Pt, leading to the negative charging of the Pt atoms as evidenced by reduced Pt 2p-to-5d electron-transition intensity detected by XAFS spectroscopy and the emergence of a CO adsorption band at 2063 cm–1 in DRIFTS. The significance of EMSIs is manifested by comparing the CO oxidation activity over the Pt–Co(OH)2/SiO2 and Pt/SiO2 catalysts with similar Pt loadings. Pt–Co(OH)2/SiO2 is superior to Pt/SiO2 in both the apparent activation energy (19 vs 64 kJ/mol) and the turnover frequency (0.03 vs 0.003 s–1 at 37 °C). The enhanced activity is attributed to the negative charging of Pt, which downshifts the d-band center and reduces the CO adsorption strength.
研究领域:
催化化学
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材料科学
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纳米技术
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表面化学
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高影响因子
Catalysis Science & Technology
·
2025
·
IF 4.2
Canyang Zhang,Yin Liang,Chao Chen,Wei Zhao,Bolong Li,Jianghao Wang,Zhenyu Zhang,Huiping Ji,Feng Zhou,Kaige Wang,Reinout Meijboom,Jie Fu
The decarbonylation of biomass-derived fatty acids (CnH2n+1COOH) presents a sustainable method for producing high-value alkenes (CnH2n). However, the development of efficient and highly selective catalysts for fatty acid decarbonylation remains challenging. In this work, we prepared a series of CoPhPhen/MWCNT-X catalysts by pyrolyzing a 4,7-diphenyl-1,10-phenanthroline (PhPhen) Co complex immobilized on multi-walled carbon nanotubes. In the model decarbonylation reaction of stearic acid, the optimized CoPhPhen/MWCNT-900 catalyst demonstrated remarkable catalytic efficacy, with 81.6% conversion of stearic acid and 58.3% yield of heptadecene. Characterization and comparative experiments demonstrated that the substantial phenyl groups in the PhPhen ligand engage in strong π-π interactions with the MWCNT, effectively inhibiting the migration and aggregation of cobalt single atoms during pyrolysis and thus maintaining a high density of active Co single-atom sites. Further electronic structure investigation revealed that the local electron density around the cobalt species markedly rises with higher pyrolysis temperatures, and this electronic impact exhibits a distinct positive association with the decarbonylation performance of catalysts. In situ DRIFTS was employed to reveal the adsorption and reaction process of fatty acids on the Co single-atom active sites: The fatty acid molecule first coordinates to the cobalt center via the carbonyl oxygen, followed by successive dehydration and decarbonylation processes, finally yielding H2O, CO, and olefins.
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COLLOID AND POLYMER SCIENCE
·
2023
·Vol. 301
·期 5
·445-453
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IF 2.4
Li Bin,Hao Wenrui,Xu Xiaojia,Liu Jizhen,Fu Dandan,Zhou Mengjing,Hu Zhigang
Choline chloride (ChCl) was used as the hydrogen bond acceptor (HBA) and acrylic acid (AA) and acrylamide (AM) as the hydrogen bond donor (HBD), and the three materials were mixed in a certain molar ratio to obtain deep eutectic solvent (DES). Subsequently, P(IA-co-AA-co-AM) composite hydrogels were prepared by adding itaconic acid (IA) to DES using the frontal polymerization (FP) method. The hydrogels were characterized by Fourier infrared spectroscopy (FTIR) and scanning electron microscopy (SEM), and the influence patterns of IA content on the mechanical properties, swelling properties, and pH responsiveness of the composite hydrogels were investigated. The results showed that the composite hydrogel exhibited a homogeneous porous structure. The elongation at the break of the composite hydrogel gradually increased with the increase of IA content, and the elongation of the FP4 sample reached 167%. The addition of IA increased the number of hydrophilic groups, resulting in a 2.14-fold increase in the equilibrium swelling of the composite hydrogel in distilled water. P(IA-co-AA-co-AM) composite hydrogels exhibit different swelling patterns in acidic and alkaline environments, making them promising for acid–base indicators, biosensors, and other applications. In this study, a simpler and greener method was proposed to prepare P(IA-co-AA-co-AM) composite hydrogels with pH responsiveness.
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高影响因子
JOURNAL OF ELECTRONIC MATERIALS
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2022
·Vol. 52
·期 2
·1375-1384
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IF 2.047
Shi Chonghua,Fu Hang,Nie Jiajin,Yao Shaowei
A composite material of Co/N-doped porous carbon was derived from a zeolite imidazolate framework (Zn/Co-ZIF) precursor, which exhibited a controllable microstructure and high specific surface area. In order to study the microwave absorption properties of the composites, the Zn/Co-ZIFs were heat-treated at 930°C in a N 2 atmosphere to obtain the composites, in which Co nanoparticles were distributed uniformly in N-doped porous carbon (Co/C composites). Through N 2 adsorption and desorption testing, the specific surface area of the Co/C composites was about 333.5 m 2 g −1 , and the Barrett−Joyner−Halenda (BJH) pore size distribution was 5.7131 nm, with the majority of pores at mesoporous scale. The microwave absorption properties of Co/C composites with different content were then analyzed, revealing that the Co/C composite with absorbent content of 15 wt.% had the smallest reflection loss (−46.36 dB) at a thickness of 3.1 mm. Based on these results, the Co/C composites not only have the advantages of high specific surface area and special porous structure, but with the appropriate absorbent content, the Co/C composites show excellent microwave absorption performance.
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高影响因子
Aggregate
·
2023
·
IF 18.8
Xiao Chen,Lei Wang,Yan Gao,Yang Li,Xiaowei Zhang,Yu Jiang,Ge Wang
The photothermal conversion capacity of pristine organic phase change materials (PCMs) is inherently insufficient in solar energy utilization. To upgrade their photothermal conversion capacity, we developed bimetallic zeolitic imidazolate framework (ZIF) derived Co/N co-doped flower-like carbon (Co/N-FLC)-based composite PCMs toward solar energy harvesting. 3D interconnected carbon framework with low interfacial thermal resistance, abundant carbon defects and high content of nitrogen doping, excellent localized surface plasmon resonance (LSPR) effect of Co nanoparticles, and light absorber Co 3 ZnC in Co/N-FLC synergistically upgrade the photothermal capacity of (polyethylene glycol) PEG@Co/N-FLC composite PCMs with an ultrahigh photothermal conversion efficiency of 94.8% under 0.16 W/cm 2 . Uniformly anchored Co and Co 3 ZnC nanoparticles in carbon framework guarantee excellent photon capture ability. Bridging carbon nanotubes (CNTs) in 2D carbon nanosheets further accelerate the rapid transport of phonons by constructing cross-connected heat transfer paths. Additionally, PEG@Co/N-FLC exhibits a thermal energy storage density of 100.69 J/g and excellent thermal stability and durable reliability. Therefore, PEG@Co/N-FLC composite PCMs are promising candidates to accelerate the efficient utilization of solar energy.
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高影响因子
JOURNAL OF CHEMICAL SCIENCES
·
2022
·Vol. 134
·期 2
·1-11
·
IF 2.15
Yu Miao,Ji Shuai,Li Zhifang,Song Kun,Li Yueyu,Yang Jian,Yang Changlong
A simple ion-exchange method is used to prepare Mn and Co-supported TNU-9 denitration catalyst for NH 3 -SCR. The denitration activity and H 2 O/SO 2 resistance performance of the catalyst are systematically studied. The denitration activity test exhibits that the NO x removal rate of Mn-Co/TNU-9 is higher than that of Mn/TNU-9 and Co/TNU-9, the NO x removal rate is greater than 90% and the N 2 selectivity is greater than 99% in the range of 150 ~ 450 °C. It is because the redox cycle of Mn 4+ + Co 2+ ↔ Mn 3+ + Co 3+ improves the redox performance of the catalyst, which is conducive to the conduction of electrons, and then accelerates the oxidation of NO to NO 2 to produce a "fast SCR" reaction, and finally optimizes the overall SCR performance. Furthermore, the change is not significant for the catalytic activity over Mn-Co/TNU-9 in the presence of water. However, the sulfur resistance is poor at low temperatures due to the presence of ammonium bisulfate. It also has excellent catalytic stability. Therefore, supported TNU-9 catalysts will have a good development prospect in denitrification. Graphical abstract Mn-Co co-doped TNU-9 catalyst was successfully synthesized by simple ion exchange method and applied in the NH 3 -SCR. The results show that Mn-Co/TNU-9 catalyst has an excellent wide activity window in a wide temperature range of 150-450°C (NO x conversion over 90%), which is because Mn+Co 2+ ↔Mn+Co improves the redox performance and facilitates the electron transfer, which further accelerates the oxidation of NO into NO 2 that could result in the “Fast SCR” reaction. The synergistic effect between Mn and Co bimetallic can also improve activity. Moreover, Mn-Co/TNU-9 has very good catalytic stability.
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高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2023
·
IF 6.2
Xinle Wang,Jin Chen,Yuzhao Ma,Jianye Shi,Yueying Wang,Xiaofeng Yang,Meidan Que,Yuxi Zhou,Yanjun Li
Two-dimensional (2D) transition metal carbide MXene (Ti 3 C 2 T x ) exhibits great potential in electromagnetic wave (EMW) absorbing materials due to its abundant surface functional groups and defects, tunable conductivity and high specific surface area. The Co@NC/TiO 2 /C composites were successfully synthesized through a solvothermal method and carbonization process using Ti 3 C 2 T x /Co-BTC as precursor. The incorporation of magnetic metal Co nanoparticles and Rutile-TiO 2 effectively addresses the issue of single loss mechanism in Ti 3 C 2 T x . The results show that CTC-100 exhibits excellent EMW absorption performance with a minimum reflection loss (RL) value of −51.3 dB at a thickness of only 1.48 mm, and the corresponding effective absorption bandwidth is (EAB, RL < −10 dB) 4.3 GHz. Simultaneously, by adjusting the matching thickness of the material from 1.29 mm to 5.0 mm, the EAB can achieve 15.42 GHz (from 2.85 GHz to 18 GHz). The excellent EMW absorption performance of CTC-100 composite is primarily attributed to the synergistic effect of magnetic loss and dielectric loss. This study provided an effective strategy for the design of Ti 3 C 2 T x -based EMW absorbing materials with high absorption intensity, reduced thickness, and broad effective absorption bandwidth (EAB).
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高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2020
·
IF 7.489
Hao Gu,Qin Zhong,Yiqing Zeng,Shule Zhang,Yunfei Bu
The supercapacitive performance of high-rate capacity and long-term cycling stability is still a big challenge for electroactive materials. Herein, Ni and Zn co-substituted Co carbonate hydroxide (NiZn-CoCH) flowers array is self-assembled on nickel foams (NFs) using l -ascorbic acid as a nanostructure inducer. The NiZn-CoCH flowers, consisting of silk-like nanosheets, are deservedly large electrode-electrolyte contact area and suitable ion-diffusion channel. The nanostructure and Ni and Zn co-substitution significantly improve energy storage performance. This electrode exhibits a high specific capacitance of 2020.8 F g −1 at 1 A g −1 with high-rate capacity (remain 80.2% at 10 A g −1 ) and 5000-cycle stability (almost unchanged after 1500 cycles at 10 A g −1 ). Additionally, an assembled asymmetric supercapacitor (ASC) device of NiZn-CoCH//activated carbon (AC) achieves a high energy density of 29.6 Wh kg −1 at a power density of 375 W kg −1 and only a 0.5% decrease of the capacitance after 2500 cycles. This facile and novel preparation method, using l -ascorbic acid, may be promising for industrial production of electroactive materials for the high-performance energy storage and conversion devices.
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DOI
PubMed
高影响因子
Molecular Catalysis
·
2017
·
IF 0
Fang Dong,Yinshuang Zhao,Weiliang Han,Haijun Zhao,Gongxuan Lu,Zhicheng Tang
Despite tremendous efforts, developing a series of heterogeneous catalysts for CO oxidation elimination with high activity at low cost remains a great challenge. Here, we report a bifunctional Co-based nanocrystals anchoring in the graphene oxide layer as a high-performance catalyst for CO oxidation. Although a single cobalt or graphene oxide catalysts alone have the lower catalytic activity, their combination exhibits an unexpected, surprisingly high CO activity that is further enhanced by a series of oxygen-containing functional groups on the surface of graphene oxide sheets. The Co/graphene oxide calcined at 300 °C (Co/GO–300 °C) exhibits the outstanding catalytic activity with T 100 = 51 °C but superior stability, producing a high-performance non-precious metal-based catalyst for CO oxidation elimination. Under a series of critical characterizations, the unusual catalytic activity of Co/GO–300 °C sample is attributed to the synergistic effect between the oxygen-containing functional groups of graphene oxide sheets and Co species. Especially, the existence of Co 3+ species could promote the adsorption and activation of CO molecules.
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INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Meijing Cao,Jing Tian,Yang Zhou,WenLong Liu,Jin Dang,Weibing Li,Jiarun Li,Lei Wang
The low electrical conductivity and catalytic activity of transition metal sulfides have been identified as the primary factors limiting their application in the field of electrocatalytic water splitting. In this study, FeS 2 and Co-FeS x were initially synthesized through a hydrothermal method, followed by further annealing in an NH 3 atmosphere to obtain Co,N-FeS x . The introduction of Co led to adjustments in the electronic structure, resulting in the formation of FeS 2 /FeS (FeS x ) heterojunctions that facilitated accelerated charge transfer. Simultaneously, Co element doping increased the electrochemical active surface area, providing more active sites for the reactions. N element doping, on the other hand, introduced sulfur vacancies, thereby enhancing electrical conductivity and improving charge transfer efficiency. As a result, Co,N-FeS x exhibited significantly higher activities for the oxygen evolution reaction (OER) and overall water splitting compared to FeS 2 , with overpotentials of 290 mV and 330 mV, respectively, at a current density of 10 mA cm −2 . Furthermore, the catalyst demonstrated excellent stability. The designed structure of the catalyst provides theoretical support for the study of Fe-based catalysts in OER and overall water splitting.
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高影响因子
Small
·
2024
·
IF 13
Diancheng Duan,Junlang Huo,Jiaxiang Chen,Bin Chi,Zhangsen Chen,Shuhui Sun,Yang Zhao,He Zhao,Zhiming Cui,Shijun Liao
Single-atom metal-doped M–N–C (M═Fe, Co, Mn, or Ni) catalysts exhibit excellent catalytic activity toward oxygen reduction reactions (ORR). However, their performance still has a large gap considering the demand for their practical applications. This study reports a high-performance dual single-atom doped carbon catalyst (HfCo–N–C), which is prepared by pyrolyzing Co and Hf co-doped ZIF-8 . Co and Hf are atomically dispersed in the carbon framework and coordinated with N to form Co–N 4 and Hf–N 4 active moieties. The synergetic effect between Co–N 4 and Hf–N 4 significantly enhance the catalytic activity and durability of the catalyst. In an acidic medium, the ORR half-wave potential ( E 1/2 ) of the catalyst is up to 0.82 V , which is much higher than that of the Co–N–C catalyst without Hf co-doping (0.80 V). The kinetic current density of the catalyst is up to 2.49 A cm −2 at 0.85 V , which is 1.74 times that of the Co–N–C catalyst without Hf co-doping. Moreover, the catalyst exhibits excellent cathodic performance in single proton exchange membrane fuel cells and Zn–air batteries. Furthermore, Hf co-doping can effectively suppress the formation of H 2 O 2 , resulting in significantly improved stability and durability.
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PubMed
高影响因子
FOOD HYDROCOLLOIDS
·
2024
·
IF 11
Xin Guan,Zhuocheng Fei,Luyi Wang,Guohui Ji,Guocheng Du,Zhenwu Ma,Jingwen Zhou
Cultured meat has attracted widespread interest and research due to its sustainable meat production through innovative technologies. Recently, studies have been carried out on manufacturing muscle or fat tissue for application in cultured meat, but it remains a challenge to engineer and produce cultured meat integrating both muscle and fat tissues. Herein, it is aimed to simultaneously assemble porcine muscle stem cells (pMuSCs) and adipose-derived mesenchymal stem cells (pAMSCs) by 3D bioprinting and to develop a co-differentiation approach to manufacture cultured streaky pork (CSP) with well-defined muscle and fat compositions. Previously, we have fabricated a collagen-chitosan composite hydrogel that efficiently supported the 3D proliferation and differentiation of pMuSCs. In this work, we first determined a composite hydrogel consisting of fibrinogen and sodium alginate for the 3D culture of pAMSCs. Next, for the two bioinks encapsulating pMuSCs and pAMSCs, respectively, we obtained the optimal cell loading number and printing parameters (pressure and speed) of an extrusion bioprinter and developed a co-differentiation approach that induced both myogenic differentiation of pMuSCs and adipogenic differentiation of pAMSCs. Furthermore, we fabricated meat-like 3D constructs by co-printing two bioinks and then induced both myogenesis and adipogenesis with the co-differentiation approach, thereby producing CSP containing both muscle and fat tissues. The textural and nutritional assessment demonstrated that the CSP possessed the cooking properties and eating qualities of meat products. This work provides innovative strategies and technical references for the production of cultured meat with tissue composition and spatial structure closer to real meat.
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高影响因子
危险品化学品经营许可证（带存储）