CHEMICAL ENGINEERING JOURNAL
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2020
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IF 10.652
Fang Wang,Ting Feng,Xiujuan Jin,Yulin Zhou,Yanjie Xu,Yahui Gao,Haisheng Li,Jianfei Lei
Herein, a robust MOFs-derived super-carbon embedding with single atom Co/Ni anode materials for LIBs is developed by one-step annealing of the core–shell precursor ZIF-8@ZIF-67 with the introduction of dimethylglyoxime nickel as Ni source. The characterization results clearly indicate that atomic Co/Ni active sites accompanied with suitable CoNi nanoparticles are evenly embedded in the MOF-derived hollow rich-nitrogen carbon matrix. Simultaneously, moderate short carbon nanotubes root in polyhedral surface under the catalytic effect from the CoNi nanoparticles and construct an advanced conductive network. As a result, it delivers a high reversible lithium-ion storage capacity of 462.1 mAh g −1 at a current density of 0.5 A g −1 over 500 cycles, excellent rate performance of 223.28 mAh g −1 even at a high current density of 2 A g −1 , which is much higher than most of reported carbon-based electrode materials. The enhanced lithium storage performance mainly derives from the moderate affinity of the Li by the atomic Co/Ni active sites incorporated with their powerful catalytic effect assisting MOF-derived rich-N doped carbon base. Moreover, the superior nano-structure of the hollow rich-nitrogen carbon skeleton with in-situ grown short carbon nanotubes improves the conductivity of electrode materials, relieves the volume expansion and accelerates the migration rate of lithium ions and electrons. The theoretical calculation further confirms the superior affinity of the Li on atomic Co/Ni active sties.
研究领域:
材料科学
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能源存储
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产品关联
DOI
高影响因子
Advanced Energy Materials
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2025
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IF 26
Zongge Li,Wenjun Kang,Jingkai Lin,Rui Li,Konggang Qu,Suyuan Zeng,Lei Wang,Fanpeng Meng,Huayang Zhang,Haibo Li
The oxygen electrocatalytic activity of transition metal catalysts can be tuned by tailoring their microstructure to optimize electronic configuration. Here, a one-step Coordination-Selective Synthesis strategy is developed to integrate Co single-atom sites and Fe-based nanoparticles within the same matrix, enabling long-range electronic interactions that enhance Co-N 4 reactivity and improve oxygen reduction reaction performance. X-ray absorption spectroscopy confirmed that remote Fe-based nanoparticles modulate the electron distribution at Co-N 4 sites. Structural characterizations reveal that the optimal catalyst, Co 50% Fe 50% -NC, contains metallic Fe, Fe 3 O 4 , and Fe 4 N species. Electrochemical measurements show that it achieves onset and half-wave potentials of 0.984 and 0.927 V versus RHE, surpassing Co 100% -NC with only Co-N 4 sites. Additionally, it demonstrates efficient oxygen evolution reaction performance, achieving an overpotential of 298 mV at 20 mA cm −2 , comparable to RuO 2 . Density functional theory calculations reveal that Fe 4 N optimizes O-containing intermediate adsorption/desorption, lowering the theoretical overpotential. Zn-air batteries assembled with Co 50% Fe 50% -NC exhibited superior performance to Pt/C, highlighting its potential for bifunctional oxygen electrocatalysis. This study provides an approach for designing high-performance catalysts by utilizing synergistic interactions between atomic and nanoscale metal species.
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
高影响因子
Advanced Composites and Hybrid Materials
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2021
·Vol. 4
·期 4
·1292-1301
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IF 5.693
Zhang Pengxiang,Zhang Xihua,Li Bin,Xu Lingan,Dang Feng,Li Bao-Wen
Improving the interfacial impedance matching and attenuation ability of a microwave absorber is an important strategy to obtain excellent microwave absorbing performance. Here, we prepared an ultralight, hierarchical porous single-atom Co–N–C microwave absorber, in which evenly distributed single-atom Co is anchored in a porous N-doped carbon framework by N–Co bond via a facile bio-inspired method. These doped single atoms provide abundant highly active atomic absorption sites on the carbon skeleton, and considerable defects including pyridinic-N, pyrrolic-N, oxidized N, and so forth are introduced into the carbon framework owing to single Co atom doping. These doped single Co atoms and introduced defects act together as strong dipolar/interfacial polarization units, which lead to better impedance matching and a significant increase in attenuation capability of the absorber. The metal Co exists in form of a single atom, benefiting light weight of the absorber. Therefore, an extremely strong reflection loss (RL) value of − 60.9 dB is achieved at a lower filler content of 10 wt% with the absorber thickness of 2.5 mm, and the effective frequency bandwidth covered from 10.4 to 15.1 GHz with a thickness of 2.0 mm at a low filler content of 10 wt%. This research offers a novel route for designing a microwave absorber to improve microwave absorption performance and is expected to a wider range of absorbing materials with different structures. Graphical abstract
研究领域:
材料科学
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电磁学
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产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2018
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IF 6.14
Lanhua Yi,Fujun Lan,Jinge Li,Caixian Zhao
Photocatalytic water splitting for H2 evolution is appealing for transforming solar energy into clean chemical fuel. This technique generally requires noble metals as H2 evolution cocatalysts to facilitate efficient cleavage of water. Herein, we report a noble-metal-free TiO2 nanobelts composite photocatalyst, in which TiO2 nanobelts are supported by nitrogen-doped graphene coordinated with a single Co atom (Co-NG). The results show that Co-NG is an efficient cocatalytst for the photocatalytic H2 production over TiO2. The optimal amount of Co-NG loading is found to be 3.5 wt %, showing a H2 evolution rate of 677.44 μmol h–1 g–1 under illumination of AM 1.5 G simulated sunlight, which is close to that of platinized TiO2 nanobelts and 2.6 and 31.2 times greater than that of 3.5 wt % NG/TiO2 nanobelts composite and pure TiO2 nanobelts, respectively. The significantly improved photocatalytic activity is ascribed to the remarkable synergistic effect between single-atom Co and N-doped graphene, which serve as effective H+ reduction sites and efficient electron acceptors, respectively. Besides, the Co-NG cocatalyst also effectively retards the recombination of photoinduced charge carriers and leads to a prolonged lifetime of charge pairs. This study reveals that Co-NG is an up-and-coming candidate as cocatalyst for development of cost-effective photocatalysts for efficient solar-driven H2 evolution.
研究领域:
材料科学
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可再生能源
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Nano
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2021
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IF 15.881
Ting Huang,Yingjie Sun,Jianghua Wu,Jia Jin,Chaohui Wei,Zixiong Shi,Menglei Wang,Jingsheng Cai,Xing-Tao An,Peng Wang,Chenliang Su,Ya-yun Li,Jingyu Sun
Although lithium–sulfur (Li–S) batteries have long been touted as next-generation energy storage devices, the rampant dendrite growth at the anode side and sluggish redox kinetics at the cathode side drastically impede their practical application. Herein, a dual-functional fibrous skeleton implanted with single-atom Co–Nx dispersion is devised as an advanced modificator to realize concurrent regulation of both electrodes. The rational integration of single-atomic Co–Nx sites could convert the fibrous carbon skeleton from lithiophobic to lithiophilic, helping assuage the dendritic formation for the Li anode. Meanwhile, the favorable electrocatalytic activity from the Co–Nx species affording a lightweight feature effectively enables expedited bidirectional conversion kinetics of sulfur electrochemistry, thereby inhibiting the polysulfide shuttle. Moreover, the interconnected porous framework endows the entire skeleton with good mechanical robustness and fast electron/ion transportation. Benefiting from the synergistic effects between atomically dispersed Co–Nx sites and three-dimensional conductive networks, the integrated Li–S full batteries can achieve a reversible areal capacity (>7.0 mAh cm–2) at a sulfur loading of 6.9 mg cm–2. This work might be beneficial to the development of practically viable Li–S batteries harnessing single-atom mediators.
研究领域:
材料科学
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能源存储与转换
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
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IF 9.136
Gaozu Liao,Peng Xu,Ping Lu,Xiaojiao Qing,Zhanjiang Yu,Yu Chang,Weirui Chen,Yiming Tang,Jing Wang,Xi Wang,Xukai Li,Laisheng Li,Dehua Xia
Single Co atoms dispersed on CMK-3 was synthesized and employed as efficient catalyst to degrade APAP in O 3 /PMS process. The results of morphology and structure characterization indicated that the as prepared catalyst possessed uniform array of mesoporous channel structure with a long-range. Co atoms were single atomic dispersed in CMK-3 skeleton with the form of CoN 4 coordination. The BET surface area and average pore diameter of 3.6% SA Co/CMK-3 were measured as 956 m 2 /g and 3.6 nm, respectively. For APAP degradation by 3.6% SA Co/CMK-3 + PMS/O 3 process, TOC removal efficiency reached to 60% and 78.9% in initial 1 min and 15 min, respectively. The influence of initial pH was investigated and demonstrated that APAP could be efficiently mineralized in a wide pH range. In addition, high mineralization rates were also achieved for other refractory organics (nitrobenzene and sulfamethoxazole). Radical quenching experiments and ESR indicated that SO 4 •− , •OH and 1 O 2 were all responsible for APAP degradation. DFT simulations elucidated that single Co atoms and N-heteroatoms on 3.6% SA Co/CMK-3 served as dual reaction sites for PMS and O 3 decomposition, which enhanced the ROS generation and APAP mineralization.
研究领域:
环境科学
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催化
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水处理
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DOI
高影响因子
Small
·
2023
·Vol. 19
·期 33
·2301391
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IF 13.3
Wenjing Zhang,Jian Zheng,Ruoyu Wang,Li Huang,Junkai Wang,Tianran Zhang,Xiangfeng Liu
Lithium–oxygen (Li–O 2 ) batteries have received extensive attention owing to ultrahigh theoretical energy density. Compared to typical discharge product Li 2 O 2 , LiOH has attracted much attention for its better chemical and electrochemical stability. Large-scale applications of Li–O 2 batteries with LiOH chemistry are hampered by the serious internal shuttling of the water additives with the desired 4e − electrochemical reactions. Here, a metal organic framework-derived “water-trapping” single-atom-Co-N 4 /graphene catalyst (Co-SA-rGO) is provided that successfully mitigates the water shuttling and enables the direct 4e − catalytic reaction of LiOH in the aprotic Li–O 2 battery. The Co-N 4 center is more active toward proton-coupled electron transfer, benefiting - direction 4e − formation of LiOH. 3D interlinked networks also provide large surface area and mesoporous structures to trap ≈12 wt% H 2 O molecules and offer rapid tunnels for O 2 diffusion and Li + transportation. With these unique features, the Co-SA-rGO based Li–O 2 battery delivers a high discharge platform of 2.83 V and a large discharge capacity of 12 760.8 mAh g −1 . Also, the battery can withstand corrosion in the air and maintain a stable discharge platform for 220 cycles. This work points out the direction of enhanced electron/proton transfer for the single-atom catalyst design in Li–O 2 batteries.
研究领域:
材料科学
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电化学
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能源存储
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电池技术
✓ 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）