JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2025
·
IF 6.2
Xiong Xiao,Linpeng Zheng,Qian Li,Chunhua Chen,Duanwei He,Xiuyan Wei,Zuguang Hu,Jianyun Yang,Guodong (David) Zhan
Chemical vapour deposition (CVD) rates are limited, making the preparation of thick diamonds challenging. We propose an efficient high pressure high temperature (HPHT) welding method for polycrystalline CVD diamond films. Multiple layers of CVD polycrystalline diamond films are welded into a monolithic structure under 15 GPa and 2100 °C. HPHT treated samples have an extremely high bond strength and the hardness of the weld layer exceeds 120 GPa. Microstructural analyses suggest the mechanism of HPHT welding: laser treatment transforms the carbon atoms on the CVD diamond film surface from SP3 to SP2 hybridization, forming a non-diamond-carbon/diamond coherent interface. Under HPHT conditions, the carbon atoms are again transformed from SP2 to SP3 hybridization, forming a strong interlayer bond through diffusion at the coherent interface. This method provides a new approach for rapidly preparing diamond bulk materials.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2021
·
IF 7.963
Qiang Zhao,Chiheng Chu,Xin Xiao,Baoliang Chen
The precisely coupling of metal nanoparticles with support domain are crucial to enhance the catalytic activity and stability of supported metal nanoparticle catalysts (MNPs). Here we selectively anchor Pd nanoparticles to the sp 2 domain in graphene-based aerogel constructed with base-washed graphene oxide (BGO) by removing oxidative debris (OD). The effects of OD on the size and chemical composition of Pd nanoparticles in aerogels are initially unveiled. The removal of OD nanoparticles prompt selective coupling of Pd nanoparticles to the exposed sp 2 -hybridized domain on BGO nanosheets, and then prevent it from agglomeration. As a result, the Pd nanoparticle size of self-assembled Pd/BGA is 4.67 times smaller than that of traditional Pd/graphene oxide aerogel (Pd/GA). The optimal catalytic activity of Pd/BGA for the model catalytic reduction of 4-nitrophenol is 15 times higher than that of Pd/GA. Pd/BGA could maintain its superior catalytic activity and achieves 98.72% conversion in the fifth cycle. The superior catalytic performance could be ascribed to the small Pd nanoparticles and high percentage of Pd(0) in Pd/BGA, and the enhanced electronic conductivity of Pd/BGA. These integrated merits of Pd/BGA as heterogeneous catalysts are attributed to selectively anchor Pd nanoparticles on sp 2 -hybridized domain of graphene-based aerogel, and strongly coupled interaction of MNPs with support. The structure-regulated BGO nanosheets could serve as versatile building blocks for fabricating MNPs/graphene aerogels with superior performance for catalytic transformation of water pollutants .
研究领域:
材料科学
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催化化学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2022
·
IF 9.224
Juan Zhang,Juncheng Wu,Taotao Guan,Guoli Zhang,Shengqin Guan,Jie Han,Jianlong Wang,Kaixi Li,Zhichang Liu
Advances in high-performance transition-metal–nitrogen–carbon catalysts (M–N–Cs) for the oxygen reduction reactions (ORR) are high-profile efforts to realize the large-scale implementations of rechargeable zinc–air batteries. However, it is extremely desirable but challenging to achieve stable active sites and excellent electron transport capability for M–N–C catalysts. Herein, spherical porous M–N–Cs (denoted as NPCS-Fc) with tailoring of the sp2-C/sp3-C ratio in carbon shell were prepared from low-cost coal tar pitch (CTP) via an acid-treatment-introduced defect-assisted one-step pyrolysis strategy. Due to the tradeoff among activity, conductivity, and stability, NPCS-Fc exhibits excellent ORR performance with a half-wave potential (E1/2) of 0.863 V, a low Tafel slope of 59 mV dec–1, and long-cycle durability in alkaline media. As the air cathode, the assembled rechargeable zinc–air battery delivers a high OCV of 1.538 V and a specific capacity of 870 mAh gzn–1. The enriched sp2-C atom strategy to give M–N–C materials opens up a facile way for developing high-performance catalysts in flexible, rechargeable zinc–air batteries.
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
JOURNAL OF POWER SOURCES
·
2025
·
IF 7.9
Kunyu Zhao,Yuhang Xin,Qingbo Zhou,Bojian Fan,Hexiao Zhang,Shaowen Huang,Feng Wu,Hongcai Gao
The sodium storage performance of hard carbon (HC) derived from biomass is influenced by the composition and structure of the precursor. The changes in carbon structure resulting from pyrolysis pretreatment, and their modulation of HC properties, require systematic investigation. Herein, different pretreatments were employed to obtain HC containing varying degrees of oxygen functionalities, which are demonstrated to result in a non-negligible effect. We confirmed the presence of the effective oxygen-containing functional groups by Fourier transform infrared spectroscopy (FTIR) and found these further affected the structure of HC. Intriguingly, the controlled effect was found to enhance the proportion of sp 2 -hybridized carbon configuration so that the diffusion of sodium ions and the transport of electrons were tuned. Furthermore, rich defects caused by variation of oxygen functionalities serve as reversible active sites for sodium storage. The HC showcases an excellent specific capacity (378.1 mAh g −1 at 0.1 C), based on the participation of oxygen functionalities in the formation process, accounting for 302.0 Wh kg −1 of full cell. The insights for the mechanism by which the electrochemical performance of HC is affected by oxygen functionalities, which provide a rational method to design biomass-based HC anode with high performance.
研究领域:
储能
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材料科学
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电化学
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纳米技术
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可持续能源
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2018
·Vol. 10
·期 23
·10999-11005
·
IF 7.233
Chunping Ruan,Zhi Yang,Huagui Nie,Xuemei Zhou,Zeqing Guo,Lu Wang,Xingwei Ding,Xi'an Chen,Shaoming Huang
The current challenge in the development of high-performance lithium–sulfur (Li–S) batteries is to facilitate the redox kinetics of sulfur species as well as to suppress the shuttle effect of polysulfides, especially at high current rates. Herein, aiming the application of Li–S at high current rates, we coupled a sp2 carbon configuration consisting of 3D carbon nanotubes/graphene prepared by ultrahigh temperature treatment (2850 °C) with S (2850CNTs–Gra–S) for application in Li–S batteries. The 2850CNTs–Gra as the host material exhibits a nearly perfect sp2 hybridized structure because ultrahigh temperature treatment not only repairs the raw defects in CNTs and graphene, but it also forms new sp2 C–C bonds between them. The 3D sp2 carbon network ensures ultrafast ion/electron transfer and efficient heat dissipation to protect the integrity of the separator when the Li–S battery is running at an ultrahigh rate. Based on these unique advantages, the 2850CNTs–Gra–S cathode shows a high current rate performance. Critically, it still delivers a considerable specific capacity after 1500 cycles even at a current rate of 15C and exhibits an extremely low capacity degradation rate of 0.0087% per cycle.
研究领域:
电化学储能
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材料科学
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纳米碳材料
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能源化学
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电池技术
✓ 已验证
DOI
高影响因子
Catalysts
·
2025
·Vol. 15
·期 9
·850
·
IF 4
Qiongqiong He,Xuewen Wu,Ping Ma,Zhaoyang Song,Xiaoqi Wu,Ruize Gao,Zhenyong Miao
Phenol is a refractory organic pollutant that is difficult to degrade in wastewater treatment, and efficiently and stably degrading phenol presents a significant challenge. In this study, iron-doped humic acid-based nitrogen–carbon materials were prepared to activate peroxymonosulfate (PMS) for the degradation of phenol. The Fe-N-C/PMS system achieved a phenol degradation rate of 99.71%, which follows a first-order kinetic model, with the reaction rate constant of 0.1419 min−1. The phenol degradation rate remained above 92% in inorganic anions (Cl−, SO42−, HCO3−) and humic acid and the system maintained a 100% phenol removal rate over a wide pH range (3–9). The iron in the catalyst predominantly exists in the forms of Fe0and Fe3C, and Fe0, Fe2+/Fe3+are the main active sites that promote PMS activation during the reaction. Additionally, Fe-N-C has a large specific surface area (1041.36 m2/g). Quenching experiments and electron spin resonance (ESR) spectroscopy detected the active free radicals in the Fe-N-C/PMS system: SO4•−, •OH, O2•−, and1O2. The mechanism for phenol degradation was discussed, involving radical pathways (SO4•−, •OH, O2•−) and the non-radical pathway (1O2), in the Fe-N-C/PMS system activated by Fe0, Fe2+/Fe3+, sp2hybridized carbon, C-O/C-N, C=O, and graphitic nitrogen active sites. This study provides new insights into the synthesis of efficient carbon-based catalysts for phenol degradation and water remediation.
研究领域:
环境科学
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材料化学
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水体修复
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催化
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污染物降解
✓ 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）