INTERNATIONAL JOURNAL OF CHEMICAL KINETICS
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2024
·Vol. 56
·期 10
·596-612
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IF 1.5
Xue-qi Zhang,Qing-xian Yue,Rui Ding,Jie Liu
Corrosion protection of steel bars in alkaline concrete environments poses a common challenge in marine engineering. One approach to mitigate steel bar corrosion is the addition of corrosion inhibitors to the concrete. In alkaline environments, the passivation of rebars occurs through anodic passivation coupled with the cathodic oxygen reduction reaction (ORR). The catalysis of ORR can expedite anode passivation. To investigate the corrosion inhibition of steel bars in alkaline environments, meso-tetra(4-carboxyphenyl)porphine (TCPP), known for its ORR catalytic properties, is selected. TCPP forms adsorption films on the surface of steel bars, facilitating the formation of passivation films. TCPP primarily adsorbs onto active sites on the surface of the passivation film, where lattice iron ions have leached. The adsorbed TCPP accelerates the formation of the passivation film through ORR catalysis, inhibiting the development of passivation film defects and enhancing the integrity and protection of the passivation film. The most significant effect is observed when the concentration of TCPP is 0.5 mmol/L. The physical adsorption of TCPP is primarily determined by the negative charge centers, namely the carboxyl group O and the pyrrole N. However, due to steric hindrance caused by the unrestricted rotation of the carboxyl benzene, the pyrrole N does not play a dominant role in chemical adsorption. Instead, the active site for chemical adsorption is the carboxyl group O. The adsorption process significantly reduces the diffusion coefficient of TCPP molecules, providing a robust and stable adsorption binding. Phthalocyanine molecules without carboxyl benzene groups adopt a planar structure, allowing them to form stable adsorption configurations on the iron surface through flat adsorption. This observation provides guidance for the design of novel metal phthalocyanine molecules. Specifically, the development of metal phthalocyanine molecules with modifying groups that are coplanar with the phthalocyanine ring and possess restricted rotation can achieve flat adsorption, improve coverage rate, and enhance adsorption configuration stability.
研究领域:
材料科学
·
腐蚀工程
✓ 已验证
DOI
高影响因子
CATALYSIS TODAY
·
2025
·
IF 5.3
Xi Shen,Zhenyu Zhao,Hong Li,Xin Gao
The recycling and upcycling of waste plastics into high-value products by pyrolysis is a critical challenge caused by its time/energy-consuming problems, which can be overcome by employing microwave-assisted catalytic pyrolysis due to its rapid pyrolysis rates and high product yields. This study presents a facile method for the synthesis of catalysts for microwave-assisted pyrolysis of waste plastics, utilizing the pyrolytic products as raw materials. In this case, a microwave thermal shock strategy is developed to efficiently anchor iron nanoparticles on carbon nanotubes (CNTs). This method recycles a portion of pyrolysis products back into the catalyst pool for plastic transformation into new CNTs, reducing the consumption for preparing additional catalysts. The precursors exposed to 50 W microwave irradiation reaches above 2000 °C within seconds, allowing Fe nanoparticles to be uniformly impregnated within the carbon nanotube matrix. The formed iron-doped CNTs shows high activity for microwave-assisted pyrolysis, generating CNTs with D/G ratios at 0.31. The recycling and reconstruction of CNTs after multiple pyrolysis form a cross-lined network structure, which facilitates electron transition and can be utilized for fabricating electrocatalysts. Nitrogen doping further improves the onset potential to 0.923 V vs. RHE, making them viable candidates for electrocatalytic applications in oxygen reduction reactions. In summary, our findings demonstrate the feasibility of this approach to reactive pyrolysis products that serve as catalysis for microwave-assisted pyrolysis, with the potential to reduce volatile organic compound emissions and capital expenditure in catalyst preparation, offering a greener and more efficient pathway for plastic waste management and catalyst production.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
RUSSIAN JOURNAL OF GENERAL CHEMISTRY
·
2025
·Vol. 95
·期 6
·1455-1463
·
IF 0.8
Chen X.,Xiu X.,Zhuang X.,Sun H.,Dong C.
Developing cost-effective and efficient non-precious metal oxygen reduction catalysts (ORRs) is crucial for advancing renewable energy technologies. This study reports the synthesis and characterization of a novel non-precious metal catalyst, N–C–Fe-600, synthesized via a simple two-step method. Pyrolysis of NH 2 –MIL-88(Fe) under an inert atmosphere, followed by acidic treatment, yielded a porous N–C–Fe-600 material featuring a high surface area and a substantial concentration of active Fe–N x sites. Electrochemical characterization revealed that N–C–Fe-600 exhibits ORR activity comparable to commercial Pt/C catalysts, along with significantly enhanced stability and methanol tolerance. The catalyst demonstrates a near-ideal four-electron transfer pathway, suggesting its potential as a viable alternative to platinum-based catalysts in fuel cells.
研究领域:
材料科学
·
电化学
·
催化
·
纳米技术
·
能源技术
✓ 已验证
DOI
高影响因子
FUEL
·
2024
·
IF 6.7
Yuxi Sun,Chuangang Yao,Zhe Zhang,Baixi Xia,Haixia Zhang,Jingyi Ding,Li Zhang,Wenwen Zhang,Xiaoshi Lang,Kedi Cai
The sluggish of the oxygen reduction reaction (ORR) kinetics and the susceptibility to CO 2 interactions are major barriers to the widespread application of solid oxide fuel cells (SOFCs). In this study, a non-metal cation doping strategy was employed to enhance the ORR catalytic activity and CO 2 tolerance of SrFeO 3- δ cathode. SrFe 1- x P x O 3- δ (SFP x , x = 0, 0.05, 0.1, 0.15, 0.2) materials were synthesized by substituting phosphorus (P) for Fe in SrFeO 3- δ . The doping of P facilitated the formation of oxygen vacancies in SrFeO 3- δ , enhancing oxygen adsorption, dissociation, diffusion, and charge transfer processes, leading to a notable increase in ORR catalytic activity. At 800 ℃, the polarization resistance of SFP 0.15 was 0.08 Ω cm 2 , a reduction of 42.86 % compared to undoped SrFeO 3- δ . Additionally, SFP 0.15 achieved a peak power density of 749.36 mW cm 2 , representing a 91.99 % enhancement over SrFeO 3- δ . These findings suggest that non-metal cation doping is an effective approach to boost the performance of SrFeO 3- δ perovskite cathode.
研究领域:
材料科学
·
电化学
·
能源材料
·
燃料电池
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Chen Li,Yaowen Zhang,Min Yuan,Yang Liu,Haikuo Lan,Zhenjiang Li,Kang Liu,Lei Wang
Regulating the atomic coordination ambiance of uniformly distributed single atoms (SAs) via heteroatom doping is an up-and-coming method to facilitate the catalytic activity for oxygen reduction reactions (ORR). With the cooperative interaction of dual heteroatom doping supplied extra degrees of freedom, a greater efficiency of ORR can be realized via a reduction in intermediate energy barrier during catalytic reactions. Here, we explore a fresh approach to generate N, S co-doped Fe-SA in embedded porous carbon nanosheets/carbon nanotubes (Fe-N X @NSCST-ZL) utilizing a 2D leaf-shaped MOF as a template in this work. Taking advantage of the combined effect of carbon matrix and nanotubes as well as the abundance of Fe-N X active sites and thiophene-S, the Fe-N X @NSCST-ZL provides exceptional performance for ORRs with a half-wave potential of 0.94 V at alkaline conditions, 0.77 V at acidic conditions, and 0.74 V at neutral conditions (V vs. RHE). Furthermore, Fe-N X @NSCST-ZL-based Zn-air battery, as well as quasi solid-state flexible battery, maintain steady operation for 765 h and 30 h with a small discharge/charge interval, respectively. This work contributes perspectives on the reasonable design of economical single-atom catalysts (SACs) for applications in energy conversion that have outstanding electrocatalytic potential.
研究领域:
材料科学
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电化学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2018
·
IF 5.091
Dong Xiang,Xiangjie Bo,Xiaohui Gao,Cheng Du,Ping Li,Liande Zhu,Wei Chen
Nonprecious-metal electrocatalysts have been intensively investigated, but how to keep a balance between their sustainability and competitive performance for the oxygen reduction reaction (ORR) is still a big challenge for energy applications. In this work, a type of bimetal- and nitrogen-codoped mesoporous carbon electrocatalyst (FeCo-N/C-800) was successfully synthesized via a simple hydrothermal method , followed by a calcination process at 800 °C in nitrogen atmosphere and an acid-etching process. The obtained FeCo-N/C-800 can act as a high-performance ORR catalyst with high onset and half-wave potentials (0.94 and 0.85 V), a large limiting current density (5.94 mA cm −2 ) and a four-electron reaction process in 0.1 M KOH solution, which can be comparable with commercial Pt/C catalyst. Additionally, the FeCo-N/C-800 exhibited superior long-term durability and high methanol tolerance. The excellent electrocatalytic performance of the FeCo-N/C-800 can be ascribed to the mesoporous structure (bimodal pores system), the synergetic interaction of the multiple ORR active sites, suitable N-doping level and the highly conductive carbon matrix. These structural features can promote efficiently the mass and electron transfer , provide abundant active sites for the adsorption and reaction of oxygen molecules, and thus improve the reaction kinetics. The present study not only provides a strategy for the synthesis of carbon-based electrocatalyst with high ORR catalytic activity and stability, but also demonstrates that the bimetal- and nitrogen-codoped carbon materials could be a class of competitive candidate for non-noble metal-based electrocatalysts.
研究领域:
电化学
·
材料科学
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能源材料
·
催化
✓ 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）