CHEMICAL ENGINEERING JOURNAL
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2022
·
IF 16.744
Yaqian Dong,Zhi Fang,Deliu Ou,Qing Shi,Yu Ma,Weiyou Yang,Bin Tang,Qiao Liu
Constructing inexpensive, efficient, and stable pH-universal oxygen reduction electrocatalysts with controlled distribution of active species is of great importance for the exploration of green energy conversion devices. Herein, we demonstrated the rational preparation of S-modified Fe–N–C nanosheet catalysts with hierarchical porous architecture, large specific surface area (up to 1471 m 2 g −1 ) and controlled S doping (up to 12.3 at.%) by the co-pyrolysis of cysteine, FeCl 3 with Zn-mediated MgO template. Merited from rich and accessible active sites, the catalysts display outstanding oxygen reduction reaction (ORR) activity in terms of very small E j3 (potential@3 mA cm −2 , 0.87 V in 0.1 M KOH, 0.66 V in 0.1 M PBS (pH7.4) and 0.64 V in 0.5 M H 2 SO 4 ) and overwhelming diffusion-limited current density (9.8, 6.1, 10.3 mA cm −2 in alkaline, neutral, acidic media, respectively), along with extremely respectable stability (∼90% activity retention for 53200, 26728, 43200 s in alkaline, neutral, acidic media, respectively), which underscore comparable or even better overall performance than commercial Pt/C and advanced pH-universal ORR catalysts ever reported. The as-assembled primary alkaline zinc–air battery delivers considerately large peak power density of 205 mW cm −2 and energy density up to 990.6 Wh kg Zn −1 at 10 mA cm −2 (115 mW cm −2 and 676.7 Wh kg Zn −1 for Pt/C-based battery), implying its highly promising application in practical energy conversion devices.
研究领域:
材料科学
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能源化学
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DOI
高影响因子
Nanoscale
·
2024
·Vol. 16
·期 10
·5215-5221
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IF 5.8
Yangdong Zhou,Junda Chen,Zhiyin Huang,Yuqin Peng,Lixin Xing,Chunmei Tang,Ning Wang,Ling Meng,Mingjie Wu,Lei Du,Siyu Ye
The cathodic oxygen reduction reaction (ORR) has been continuously attracting worldwide interest due to the increasing popularity of proton exchange membrane (PEM) fuel cells. So far, various Pt-group metal (PGM) or PGM-free catalysts have been developed to facilitate the ORR. However, there is still a gap to achieve the expected goals as proposed by the U.S. Department of Energy (DoE). Recently, PGM-free@PGM hybrid catalysts, such as the M/N/C@PtM catalyst, have achieved the milestones of oxygen reduction, as reviewed in our recent work. It is, nevertheless, still challenging to unravel the underlying structure–property relationships. Here, by applying different Pt/Co ratios, a series of Co/N/C@PtxCo catalysts are synthesized. Interestingly, the ORR activity and stability are not linear with the Pt content, but show a volcano-like curve with increased Pt usage. This relationship has been deeply unraveled to be closely related to the contents of pyrrolic N, pyridinic N, and graphitized carbon in catalysts. This work provides guidelines to rationally design the coupled PGM-free@PGM catalysts toward the ORR by appropriate surface engineering.
研究领域:
材料科学
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电化学
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催化科学
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产品关联
DOI
PubMed
高影响因子
CATALYSIS LETTERS
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2021
·Vol. 151
·期 10
·3004-3010
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IF 3.186
Zhou Junjie,Huang Yu,Shen Jialu,Liu Xiang
The production of H 2 from non-fossil sources is a key research challenge to contributing solving the forthcoming energy problem. Aqueous solutions of tetrahydroxydiboron have very recently appeared as a H 2 source, from which both hydrogen atoms are provided by water, in the presence of highly sophisticated nanocatalysts. Herein, commercial and cheap Pd/C is shown to be an efficient and recyclable catalyst for H 2 evolution upon tetrahydroxydiboron hydrolysis. Graphic Abstract
研究领域:
化学
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能源科学
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产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2019
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IF 14.229
Anquan Zhu,Lulu Qiao,Pengfei Tan,Yongjin Ma,Weixuan Zeng,Rui Dong,Cheng Ma,Jun Pan
It still requires further investigations on the status of iron-based compounds and actual active sites in iron and nitrogen modified carbon based oxygen reduction catalysts (Fe N C), even though Fe-N x groups have been confirmed as a type of dominating active site for most Fe N C systems. Herein, a facile and practical surface engineering process is adopted to transform metallic iron and iron trioxide nanoparticles into Fe 2 N nanocrystals, meanwhile to make their coated graphitic carbon shells interrupted and broken. This sufficiently facilitates the elimination of embedded Fe 2 N with a subsequent acid-etching process, eventually obtaining AA-Fe 2 N@NC sample. Based on various physicochemical characterizations, it is found that the relative concentrations of defective carbon and pyridinic N for AA-Fe 2 N@NC are clearly enhanced, compared to its counterpart (Fe 2 N@NC sample). Electrochemical measurements demonstrate that AA-Fe 2 N@NC instead of Fe 2 N@NC has optimal onset potential (72 mV positive shift), half-wave potential (45 mV positive shift) and limiting current density values (increased by 0.97 mA cm −2 ). When used as an air cathode of rechargeable Zn-air battery, it delivers a high power density of 168.15 mW cm −2 , meanwhile a long-life cycling durability (60 h operation with an increased voltage gap of only 70 mV) is realized at 5 mA cm −2 . Combined with the calculation of TOF values and SCN - inhibition test, we make a conclusion and highlight that, in alkaline electrolyte, carbon defects and pyridinic N for this Fe N C system rather than Fe 2 N compounds or Fe-N x groups actually serve as the dominant active sites to afford a high-performance output of ORR activity.
研究领域:
材料科学
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电化学
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能源存储与转换
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产品关联
DOI
高影响因子
ACS Catalysis
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2019
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IF 12.221
Chao Hu,Silin Bai,Lijun Gao,Sucen Liang,Juan Yang,Shao-Dong Cheng,Shao-Bo Mi,Jieshan Qiu
Metal-doped zeolitic imidazolate framework-8 (ZIF-8)-derived carbon materials are attractive for the electrocatalytic reduction of CO2 into CO. In such carbon materials, due to the fusion and aggregation of ZIF-8 precursors during the high-temperature pyrolysis process, it is desirable yet still challenging to create a high specific surface area with more active sites available for reacting with reactants. Using SiO2 as a protective coating on the ZIF-8 surface, we synthesize Fe, N-co-doped porous carbon nanoparticles (Fe-CNPs) which possess a hierarchical pore structure with a specific surface area as high as 1156.6 m2 g–1, much higher than the counterparts without a SiO2 coating (360.1 m2 g–1). Over these highly porous Fe-CNPs, the total current densities are more than 3 times higher than those of the lowly porous ones for the electrochemical CO2 reduction. More importantly, the maximum CO Faradaic efficiency for Fe-CNPs increases from ca. 75.0 to 98.8% in a concentrated KHCO3 solution (1 mol L–1). The porosity-induced high selectivity for CO production is also revealed on Ni-doped and Co-doped ZIF-derived CNPs, suggesting a new pathway for designing high-performance carbon catalysts through engineering the porosity for the electrochemical CO2 reduction.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
Scientific Programming
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2022
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IF 1.672
Xiaojun Pei,Haojun Shu,Yisi Feng
In the field of catalysis, the support of the catalyst is often composed of hollow carbon materials. In order to monitor the preparation of nitrogen-doped carbon-based bimetallic copper-cobalt catalysis and its hydrogenation reaction in furfural, using m-aminophenol as the nitrogen source, formaldehyde as a carbon source, and P123 as a template agent, a nitrogen-doped bimetallic copper-cobalt mesoporous carbon catalyst Cu-Co@N-MPC-500 was synthesized by the hydrothermal method. The morphology, structure, and chemical composition of the catalyst were analyzed by means of TEM, XRD, BET, and XPS, respectively. The results show that the nitrogen-doped mesoporous carbon has a stable structure, uniform pore size distribution, and the nano-copper-cobalt particles are uniformly dispersed in the mesoporous carbon surface. Through furfural hydrogenation, the catalyst selectivity and cycle stability were discussed. Under the furfural conversion rate of 96.1%, the yield of cyclopentanone could reach 76.2%. After 5 cycles, the catalytic efficiency of the catalyst did not decrease significantly. It shows that Cu-Co@N-MPC-500 has excellent application prospects in the field of industrial production.
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2021
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IF 5.316
Chen Zhe-qin,Zhong Xiao-cong,Xie Yong-min,Liu Jia-ming,Xu Zhi-feng,Wang Rui-xiang
Metal–air batteries have shown tremendous potential as devices for electrical energy storage and conversion; however, their commercial applications are limited owing to the high costs of precious metal catalysts. In this study, urea was employed as a dispersant and as an additional nitrogen source to synthesize zeolitic imidazolate framework-derived iron-nitrogen-carbon catalysts (ZIF-8-derived Fe-NCs). The fabricated nitrogen-rich catalyst was found to have a high specific surface area and numerous surface defects, while maintaining the original ZIF-8 morphology. Electrochemical analysis with a rotating ring-disk electrode revealed that the onset potential of nitrogen-rich Fe-NC was 0.91 V at 1600 rpm with a limiting current density of 5.38 mA·cm −2 , which indicated a high catalytic activity for the oxygen reduction reaction. Additionally, the decent stability of the catalyst was confirmed by a 2 h cycle test.
研究领域:
材料科学
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电化学
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能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Energy
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2021
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IF 7.311
Huiyu Gai,Song Xue,Xingkun Wang,Jian Zhou,Heqing Jiang,Minghua Huang
Fabricating highly efficient catalysts toward oxygen reduction reaction (ORR), especially carbon-based metal-free ones, plays a crucial role in large-scale applications of various renewable energy conversion devices. However, the poor electrocatalytic performance of these carbon catalysts severely hinders their application because most active sites are deeply buried inside the carbon framework and fail to be accessible for the reactants. In this work, we fabricate multimodally porous N-doped dual-carbon catalyst with a sandwich-like structure, that is, N-doped mesoporous carbon spheres loaded on reduced graphene oxide nanosheets (N-MCS@rGO). The obtained catalysts exhibit interconnected hierarchical microporous/mesoporous/macroporous structure and a high specific surface area, which can simultaneously maximize the efficient utilization of active sites and facilitate mass transport, resulting in superior alkaline ORR activities. The half-wave potential of the N-MCS@rGO was ~0.85 V vs. reversible hydrogen electrode (RHE) in 0.1 M KOH, preceding most of the non-noble metal catalysts and comparable with ~0.86 V vs. RHE of commercial 20 wt% Pt/C catalysts. The established Zn-air batteries using the N-MCS@rGO as the air cathode exhibit a high power density of 100 mW/cm 2 , outperforming the commercial Pt/C catalyst-based battery. This work supplies an interesting avenue in the rational construction of multidimensional hierarchically porous materials for advanced energy conversion technologies.
研究领域:
材料科学
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能源化学
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产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
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2022
·Vol. 97
·期 10
·2805-2814
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IF 3.709
Shuaibin Zhang,Bochao Yan,Zhihui Chen,Suping Zhang
BACKGROUND Levulinic acid, an important platform compound, is extensively used in textiles, dyes, antifreeze, animal feed, solvents and food additives. However, the use of lignocellulosic biomass to produce levulinic acid is difficult because of poor accessibility to cellulose and low hydrolytic yield. Thus a viable hydrolysis strategy and a suitable catalyst must be developed. RESULTS In this study, a bifunctional solid acid catalyst (HTC-SO 3 H) containing both cellulose binding sites ( Cl, COOH and OH) and catalytic sites ( SO 3 H) was prepared by a carbonization–grafting–oxidization method. X-ray photoelectron spectroscopy and Fourier transform infrared characterization confirmed the existence of Cl and the successful modification of the SO 3 H grafted hydrothermal carbon. The hydrogen bonds formed between cellulose and the binding sites ( Cl, OH and COOH) in the catalyst showed synergistic effects with the catalytic sites ( SO 3 H), leading to efficient hydrolysis of the furfural residue. A total of 74.81% (non-magnetic) and 70.18% (magnetic) levulinic acid yields were obtained after hydrolysis at 190 °C and 180 min in γ-valerolactone–H 2 O (1:1, v/v). Magnetic catalysts were synthesized using a co-precipitation method. Catalysts were recycled without any obvious reduction in catalytic activity. CONCLUSION Using sucralose as a raw material, the as-synthesized bifunctional solid acid catalyst improved the accessibility to cellulose and increased levulinic acid yield. Moreover, the grafted SO 3 H formed by hydroxyl hydration condensation exhibited superior stability. This study provides a valuable strategy for the efficient hydrolysis of lignocellulosic biomass. © 2022 Society of Chemical Industry (SCI).
研究领域:
生物化学
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催化化学
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可再生能源
✓ 已验证
产品关联
DOI
高影响因子
BIORESOURCE TECHNOLOGY
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2022
·
IF 11.889
Chihe Sun,Wenbo Wu,Haixing Chang,Rupeng Wang,Ke Wang,Nianbing Zhong,Ting Zhang,Xuefeng He,Fubao Sun,Ezhen Zhang,Shih-Hsin Ho
This study proposed a mild chlorination-sulfonation approach to synthesize magnetic carbon acid bearing with catalytic SO 3 H and adsorption Cl bifunctional sites on polydopamine coating. The catalysts exerted good textural structure and surface chemical properties (i.e., porosity, high specific surface area of >70 m 2 /g, high catalytic activity with 0.86–1.1 mmol/g of SO 3 H sites and 0.8%–1.9% of Cl sites, and abundant hydrophilic functional groups), rendering a maximum cellobiose adsorption efficiency of ∼40% within 6 h. Moreover, the catalysts had strong fracture characteristics on different α–/β–glycosidic bonds with 85.4%–93.9% of disaccharide conversion, while selectively fractionating hemicellulose from wheat straw with 64.3% of xylose yield and 93.4% of cellulose retention. Due to the stable interaction between parent polydopamine support with Fe core and functional groups, the catalysts efficiently recovered by simple magnetic separation had good reusability with minimal losses in catalytic activity.
研究领域:
生物化学
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材料科学
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可再生资源工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
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2021
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IF 8.198
Xianghai Kong,Srinivasan Vinju Vasudevan,Mengjie Cao,Jin Cai,Hanping Mao,Quan Bu
A simple hydrothermal carbonization method was used to synthesize sulfonated carbon catalysts from glucose in reflux conditions. The concentration of sulfuric acid played a specific role in preparing sulfonated hydrothermal carbon microsphere (SHCS) and sulfonated hydrothermal carbon (SHC) catalysts. All of the samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) analyses, and the influence of different reaction conditions on 5-hydroxymethylfurfural (HMF) production from fructose was investigated in microwave conditions. The effect of microwave input power and energy efficiency on HMF formation was determined to understand the role of sulfonated carbon catalysts in a water medium. Results showed that the catalyst with a moderate sulfur content and spherical stacking was beneficial to enhance the heat-transfer efficiency on the catalyst surface during microwave-assisted heating, thus effectively enhancing the energy efficiency of the fructose dehydration reaction. The optimum reaction condition for HMF production was obtained at microwave input power 60 W, reaction temperature 186 °C, and reaction time 10 min. At this condition, the HMF yield and the energy efficiency were 88.3 mol % and 0.147 mmol kJ–1, respectively. Furthermore, the prepared catalyst showed good recyclability, wherein a simple reactivation process could rapidly recover the catalyst activity with 1 M sulfuric acid solution. This work provides a way to design a potential microwave-responsive catalyst that improves the energy efficiency and HMF yield for the fructose–HMF conversion process.
研究领域:
化学工程
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催化科学
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可再生资源利用
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2024
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IF 8.1
Xiaohan Sun,Xianghao Meng,Qiaoxia Li,YuLin Min,Qunjie Xu
Introducing the second metal is an effective strategy to ameliorate oxygen reduction reaction (ORR) performance of cobalt and nitrogen doped carbon materials (Co-NC). In this study, Sn modulated Co-NC catalysts with enriched active sites (CoSn-NC) were synthesized by using formamide as ligand. Co and Sn bimetals coexist on nitrogen-doped carbon carriers and coordinated with nitrogen to form M − N active centers. Compared with Co-NC, CoSn -NC exhibited outstanding catalytic activity in terms of early initial potential of 1.04 V and positive half-wave potential of 0.89 V. Electrochemical testing and XPS characterization proved that the addition of Sn enriched the active site of Co-NC. More importantly, the electronic structure of Co–N is adjusted to perfect adsorption energy of the intermediate. The study puts forward a new idea and direction for optimizing single metal Co-NC catalyst.
研究领域:
材料科学
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电化学
✓ 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）