JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2024
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IF 9.4
Fang Liu,Dazhi Gao,Fangqing Wang,Pengcheng Shen,Yang Liu,Shiqing Zhang,Ying Li,Jun Zhang,Yanming Xue,Chengchun Tang
The electrocatalytic oxygen reduction reaction (ORR) is crucial for energy conversion systems such as fuel cells and metal-air batteries . Boron carbon nitrogen (BCN) is a novel functional material with a high specific surface area , excellent corrosion resistance , and outstanding electrochemical stability. These properties make BCN an effective ORR catalyst and a promising support for metal catalysts . This study leveraged the strong interaction between BCN and metals to anchor platinum nanoparticles (Pt NPs) onto the BCN surface (Pt/BCN), significantly enhancing the durability of traditional Pt/C catalysts in ORR. The half-wave potential of Pt/BCN is 0.927 V, higher than Pt/XC-72R (0.857 V) and commercial Pt/C (0.879 V). Notably, after 10,000 durability test cycles, the mass activity (MA) of Pt/XC-72R and commercial Pt/C decreased by 67 % and 75 %, respectively. Even after 50,000 cycles, Pt/BCN exhibited only a 54 % decrease in MA. Experimental data and density functional theory calculations confirmed increased electron transfer from Pt to the BCN support, indicating a strong electronic metal-support interaction (EMSI) between Pt and BCN. This strong EMSI effectively anchored the Pt NPs, preventing migration and aggregation during the ORR process. Consequently, our research introduces a novel electrocatalyst support material with significant potential for ORR and broader applications.
研究领域:
材料科学
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电化学
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能源转换系统
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产品关联
DOI
PubMed
高影响因子
FUEL
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2024
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IF 6.7
Kai Zhang,Rui Zhang,Yuxin Cui,Jiayin Shang,Xueling Wei,Sumin Wang,Siqin Jia,Ke Qin,Haiyan Zhang,Hongyan Wang,Taotao Ai,Qiguan Wang
The electrocatalytic nitrogen reduction reaction (NRR) to synthesize ammonia is an important and challenging task in chemistry, where low-cost, highly active non-metallic catalysts such as boron carbonitride (BCN) are still highly desired. Tuning the electronic environment of the active site B is an effective approach to improve the NRR performance of BCNs. However, the study on the mechanism of this effect has been seriously neglected. The diversity and controllability in atomic arrangements of BCN make it suitable for studying the relationship between the local chemical environment of boron and the catalytic properties. To this end, we design four kinds of BCN materials named as homogeneous BCN nanoribbon and BCN nanosheet enriched with B − C active sites and localized phase-separated BCN nanoribbon and BCN nanosheet rich in B − N active sites, and theoretically screen the homogeneous type BCN nanoribbons that have better NRR performances. Meanwhile, we experimentally demonstrate that the optimized charge redistribution of B atoms in BCN skeleton by tuning the electronic environment makes the B − C sites being the effective centers in NRR, and arising the excellent NH 3 productivity of 63.02 μg h −1 mg − 1 cat with a highest Faraday efficiency of 32.28 %.
研究领域:
化学
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材料科学
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电催化
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产品关联
DOI
高影响因子
Molecular Catalysis
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2023
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IF 4.6
Guichuan Xu,Huicai Zheng,Xiaoju Zhang,Wen Li,Limei Zhou,Li Qin
The Knoevenagel condensation reaction is one of the most effective methods for the formation of C–C bonds. However, developing efficient heterogeneous catalysts for the Knoevenagel condensation reaction is imperative. In this study, a series of boron carbon nitride (BCN) catalysts with adjustable active sites were designed via molecular self-assembly and calcination-temperature adjustment. The BCN materials synthesized at a calcination temperature of 750 °C (BCN-750) had the largest number of active sites and exhibited excellent activity, with a yield of 96% in the condensation reaction of benzaldehyde and malononitrile in only 4 min at room temperature. The excellent catalytic activity was attributed to the B and N species at the B–N–C sites, which functioned as acids and bases, respectively, to catalyze the Knoevenagel condensation reaction. This result was confirmed by temperature-programmed desorption of CO 2 (CO 2 TPD), temperature-programmed desorption of NH 3 (NH 3 TPD), X-ray photoelectron spectroscopy (XPS), and 11 B solid-state magic-angle spinning nuclear magnetic resonance spectroscopy. In addition, aromatic and aliphatic aldehydes were successfully converted into their corresponding products. Analysis of the catalytic mechanism revealed that the deprotonation of malononitrile to form a carbanion was the rate-determining step.
研究领域:
化学
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材料科学
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催化反应
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2022
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IF 7.392
Xue Li,Xue Zhao,Yingtang Zhou,Jiao Hu,Hucai Zhang,Xun Hu,Guangzhi Hu
Ammonia is used extensively as a raw material for fertilizers and industrial production. However, the ammonia yield of the traditional ammonia production process is far from reaching the requirements of industrial applications. Among various methods, electrochemical ammonia synthesis is the most anticipated. Density functional theory (DFT) calculations show that nanoscaled palladium (Pd) decorated on boron–carbon-nitrogen (BCN) support has great catalytic activity towards nitrate electrochemical reduction. We designed and synthesized the BC2N/Pd (both B and N atomic loading more than 20%) electrocatalysts and applied them to electrochemically convert harmful nitrate to high value-added ammonia, which performed an excellent ammonia yield rate of 1730 μg h −1 cm −2 and a high Faraday efficiency of 97.42% in water that containing 250 mM KNO 3 . Isotope labeling experiments proved that ammonia originates from nitrate reduction. At the same time, BC2N/Pd also exhibits splendid stability and durability. The outstanding electrocatalytic activity suggests good prospects in industrial applications, including the purification of ammonia and nitrate wastewater.
研究领域:
材料科学
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环境科学
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催化化学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2020
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IF 16.683
Bin Chang,Lili Li,Dong Shi,Hehe Jiang,Zizheng Ai,Shouzhi Wang,Yongliang Shao,Jianxing Shen,Yongzhong Wu,Yanlu Li,Xiaopeng Hao
From a thermodynamic point of view, electrocatalytic nitrogen reduction reaction (NRR) is possible for the carbon-based metal-free catalysts, which are gradually becoming a class of potential alternatives to metal-based catalysts. However, the clarification of true active sites and corresponding exact catalytic mechanism of metal-free catalysts is urgently required. Taking full advantage of boron “Lewis acid”, a series of boron carbonitride (BCN) materials were designed and synthesized and the “Lewis acid catalysis” sites were tuned easily by adjusting the relative contents of boron and nitrogen atoms. Boron-enriched BCN exhibited outstanding NRR performance with an ammonia yield of −8.39 μg h −1. cm −2 cat. (−41.9 μg h −1. mg −1 cat. ) and Faradaic efficiency of −9.87 %, together with excellent stability. Density functional theory calculations indicate that the boron sites of BCN enable the low energy barrier of the NRR rate-determining steps and the spontaneity of nitrogen adsorption. Our philosophy opens a new possible avenue to explore high-performance metal-free materials for nitrogen activation.
研究领域:
材料科学
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电化学
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理论计算
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DOI
高影响因子
ACS Applied Energy Materials
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2021
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IF 6.024
Yifan Liu,Rashad Ali,Jun Ma,Wei Jiao,Liangjun Yin,Chunhong Mu,Xian Jian
The hydrogen evolution reaction (HER) is an emerging renewable energy source to derive clean, efficient, and high-energy-density hydrogen fuel from electrochemical water splitting mostly by using traditional noble-metal-based catalysts. However, their scarcity has led to the emergence of carbon-based materials which are exceptionally promising alternatives for the HER. Herein, graphene capsules-decorated boron–carbon–nitride sheets are developed by pyrolyzing a mixture of pyridine borane and custom-made GCs. The 3D hollow GCs effectively increase the surface area to supplement more exposed active sites for the hydrogen adsorption/desorption reaction. The carbon-rich ternary hybrid structure favors adjusting the electrical conductivity, which provides better HER catalytic performances (overpotential of 333 mV at 10 mA cm–2) in acidic conditions. The long-term stability for 24 h and the simplest designing technique propose an effective metal-free electrocatalyst for commercial applications in the renewable energy field.
研究领域:
材料科学
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能源科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）