APPLIED CATALYSIS B-ENVIRONMENTAL
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2024
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IF 20.2
Shan Hu,Panzhe Qiao,Xinming Liang,Guiming Ba,Xiaolong Zu,Huilin Hu,Jinhua Ye,Defa Wang
Photoreduction of CO 2 and H 2 O into fuels and value-added chemicals is a promising green technology for solar-to-chemical conversion. However, improving the conversion efficiency with regulated product selectivity is a big challenge due to the sluggish dynamic transfer and insufficient active sites. Herein, we report on Pt single atoms anchored porous C 3 N 4 nanosheet photocatalyst (Pt 1 @CN) with Pt–N 4 coordination for stable and efficient CO 2 photoreduction using H 2 O as reductant. The Pt 1 @CN exhibits an evolution rate of 84.8 μmol g −1 h −1 with nearly 100% CO selectivity, outperforming most previous C 3 N 4 -based single-atom photocatalysts. Experimental and DFT calculation results reveal that the Pt–N 4 coordinated active sites promote the photogenerated electron transfer, CO 2 adsorption/activation, *COOH generation, and *CO desorption, thus accounting for the significantly improved CO 2 photoreduction activity with ∼100% CO selectivity. This study provides a deep insight into the significant roles of single-atom active sites in enhancing the CO 2 photoreduction activity and regulating the product selectivity.
研究领域:
材料科学
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环境科学
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化学
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产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
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2021
·
IF 5.165
Shizhu Song,Tian Qin,Qi Li,Yanqing Wang,Yanfeng Tang,Lifang Zhang,Xiaojuan Liu
Facile synthesis of cost-effective carbon-supported Co single atoms (Co-SAs) exhibits huge potential applications in energy storage and conversion devices. We here report the implantation of Co-SAs into hollow carbon spheres (Co-SAs-HCS) via a facile wet-chemistry strategy followed by controlled pyrolysis. Electron-rich histidine acted as a Lewis base effectively immobilizing Co2+ (Lewis acid) via the electrostatic effect and hydrogen bonds, thus achieving the scalable synthesis of Co-SAs-HCS. We constructed a series of histidine-Co2+ structure models to elucidate the formation of histidine-Co2+ complexes by analyzing their binding energy. X-ray absorption fine-structure results verify that central Co atoms with four N coordination atoms possess a non-planar Co-N4 structure. Electrochemical results indicate that the as-prepared Co-SAs-HCS catalyst shows a low potential difference (0.809 V) between the oxygen evolution reaction potential at 10 mA cm–2 and the oxygen reduction reaction half-wave potential, outperforming the commercial Pt/C catalysts (0.996 V). Moreover, an assembled Zn-air battery based on Co-SAs-HCS exhibits an unexpected long-term durability. We have demonstrated that non-planar Co-N4-1-O2 sites are the source for highly efficient adsorption and dissociation of O2 molecules and then reduction of the free energy of desorption of the intermediates by density functional theory. Our findings provide a new design insight into the exploration of advanced electrocatalysts, which will be applied in the design of green energy devices in the future.
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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DOI
高影响因子
Nature Communications
·
2024
·Vol. 15
·期 1
·1-10
·
IF 14.7
Bai Jingsen,Zhao Tuo,Xu Mingjun,Mei Bingbao,Yang Liting,Shi Zhaoping,Zhu Siyuan,Wang Ying,Jiang Zheng,Zhao Jin,Ge Junjie,Xiao Meiling,Liu Changpeng,Xing Wei
The limited durability of metal-nitrogen-carbon electrocatalysts severely restricts their applicability for the oxygen reduction reaction in proton exchange membrane fuel cells. In this study, we employ the chemical vapor modification method to alter the configuration of active sites from FeN 4 to the stable monosymmetric FeN 2 +N’ 2 , along with enhancing the degree of graphitization in the carbon substrate. This improvement effectively addresses the challenges associated with Fe active center leaching caused by N-group protonation and free radicals attack due to the 2-electron oxygen reduction reaction. The electrocatalyst with neoteric active site exhibited excellent durability. During accelerated aging test, the electrocatalyst exhibited negligible decline in its half-wave potential even after undergoing 200,000 potential cycles. Furthermore, when subjected to operational conditions representative of fuel cell systems, the electrocatalyst displayed remarkable durability, sustaining stable performance for a duration exceeding 248 h. The significant improvement in durability provides highly valuable insights for the practical application of metal-nitrogen-carbon electrocatalysts.
研究领域:
材料科学
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电化学
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能源工程
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产品关联
DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2021
·Vol. 31
·期 13
·2007877
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IF 18.808
Feng Chen,Xi-Lin Wu,Chenyang Shi,Hongjun Lin,Jianrong Chen,Yanpeng Shi,Shaobin Wang,Xiaoguang Duan
Heterogeneous Fenton-like reactions (HFLR) are promising alternative strategies to address the inherent limitations of the classic Fenton systems. Herein, a facile and scale-up approach for the synthesis of transition metal single-atom sites (SA-TM, TM = Cr, Mn, Fe, Co, Cu) coordinated onto pyrrolic N-rich g-C 3 N 4 (PN-g-C 3 N 4 ) scaffold is developed. The regulated pyrrolic N-rich SA-TM catalytic sites exhibit excellent performances for HFLR. As a model of SA-TM/PN-g-C 3 N 4 , SA-Cr/PN-g-C 3 N 4 is efficient for the catalytic oxidation of bisphenol A via HFLR under visible light with outstanding cyclic stability and wide effective pH range (3.0–11.0). The synergy of photocatalysis and single-atom catalysis leads to accelerated production and separation of charge carriers as well as the cycling of Cr 3+ /Cr 2+ couple, consequently boosting the performance in HFLR. Theoretical calculations indicate that the Cr(II)-N 4 sites with the metalloporphyrin-like structure are more reactive than the doped Cr(II) sites in the g-C 3 N 4 matrix, which act as the peroxidase-mimicking nanozyme for efficient and homolytic cleavage of peroxide O O in H 2 O 2 . This study expands the family of the iron-free Fenton-like systems and provides new strategies to the rational design and precise regulation of on-demand multifunctional single-atom catalysts for advanced water remediation.
研究领域:
环境科学
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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
APPLIED CATALYSIS B-ENVIRONMENTAL
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2024
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IF 20.2
Qingming Zeng,Yanjun Wen,Xiaoguang Duan,Xing Xu,Jing Tan,Qingyan Zhang,Yilin Liu,Qingyi Zeng
In this work, we revealed a dual-pathway nonradical oxidation (NRO) system catalyzed by Ni single atom catalyst (NiN 4 ) accommodated in the carbon nitride substrate. The monatomic Ni coordinated with four N atoms (Ni-N 4 ) is determined as the dynamic catalytic center for peroxymonosulfate (PMS) activation, showing an exceptional specific rate constant of 3.34 min −1 g −2 L −2 (29.7 times that of CN/PMS system) in oxidizing bisphenol A and other refractory organics. In situ Raman, X-ray absorption, and electrochemical analyses as well as theoretical simulations demonstrate that the Ni-N 4 sites exhibit strong interaction with PMS benefited from the modulated electronic structures, resulting in nonradical surface-bonding active complexes (NiN 4 -PMS*) and deuterogenic high-valent Ni(IV)-Oxo species. The dual-pathway NRO process will spontaneously coordinate both electron transfer process via CN matrix and direct electron transfer by Ni(IV)-Oxo for selective organic oxidation with excellent anti-interference ability and adaptability.
研究领域:
环境科学
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催化化学
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理论计算化学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2021
·Vol. 9
·期 26
·14793-14805
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IF 12.732
Yuan Gao,Xiaoguang Duan,Bin Li,Qianqian Jia,Yang Li,Xiaobin Fan,Fengbao Zhang,Guoliang Zhang,Shaobin Wang,Wenchao Peng
Persulfate-based advanced oxidation processes are promising technologies to solve water pollution. In this work, single iron atoms are anchored on three-dimensional N-doped carbon nanosheets by a chemical vapor deposition (CVD) method with ferrocene-loaded CaO as the hard template. The high surface density of Fe–N4 sites and abundant interconnected meso–macro pores are highly favorable for activating peroxymonosulfate (PMS) to produce superoxide radicals (O2˙−), giving rise to ultrahigh activity and excellent stability for pollutant degradation. Experiment and density functional theory (DFT) calculations reveal that Fe–N4 is the main active site, on which electrons transfer from C to Fe via the C–N–Fe bond to secure the low-valence state of Fe species for the redox process. This work proposes a new strategy for developing highly active single-atom materials by CVD and reveals mechanisms of PMS activation on single-atom activators.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2024
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IF 10.7
Zicheng Yang,Jiale Ni,Chengyuan Duan,Yi Feng,Jianfeng Yao
Introducing dual Lewis acidic and basic sites into carbon is a promising way to improve the catalytic efficiency of carbon-based catalysts for CO2 fixation into epoxides to produce cyclic carbonates. Here, a simple and one-step method is proposed to couple atomically dispersed Zn–N4 sites and abundant –OH/–COOH groups as hydrogen bond donor (HBD) sites in porous nitrogen-doped carbon via pyrolysis of a mixture of tea saponin, melamine and Zn(NO3)2. These HBD sites, together with atomically dispersed Zn sites, serve as Lewis acids to activate epoxides, while N-doping provides a Lewis base, favouring CO2 activation. As a result, the resulting carbon (ZNC-800) displayed high yields of >99% at 12 h for CO2 cycloaddition with different epoxides, such as epichlorohydrin, epibromohydrin, benzyl(R)-(−)-glycidyl ether, 1,2-epoxyhexane and glycidyl phenyl ether, at 80 °C and 0.1 MPa CO2. In addition, owing to its good photothermal ability, ZNC-800 can also drive CO2 cycloaddition reactions with high catalytic efficiency under light irradiation, which makes ZNC-800 a promising biomass-derived catalyst for both thermally and photothermally driven CO2 conversion.
研究领域:
化学
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环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2019
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IF 5.383
Bihua Hu,Weiwei Xie,Ruchun Li,Zhangweihao Pan,Shuqin Song,Yi Wang
Metal-N x -C based materials have emerged as one of the most promising electrocatalysts for electrochemical reduction of carbon dioxide (ERCD). Co-based macrocyclic compounds have shown unique performance, however, of which the relationship between the ligands structure surrounding Co–N 4 centers and reaction mechanism remains vague. To explore this issue, here, a series of Co-based macrocyclic compounds are elaborately chosen as model catalysts, including phthalocyanine cobalt (CoPc), cobalt (II) meso-Tetraphenylporphine (CoTp) and cobalt tetramethoxyphenylporphyrin (CoTop), which possess well-defined Co-N 4 coordinated centers but different ligands structure surrounding Co-N 4 . Electrochemical measurements show that CoPc possesses higher activity and selectivity for CO with Faradaic efficiency (FE) above 62% at −0.7 V ( vs. RHE) relative to those of CoTp and CoTop. Combining density functional theory (DFT) calculations, it can be further confirmed that CoPc is more favorable for ERCD to CO due to the rapid formation of key intermediate COOH* and the desorption of CO, demonstrating that the structure of ligands (phthalocyanine) surrounding Co-N 4 plays a crucial role in the high CO selectivity. It can be anticipated that an exclusive strategy will pave a new avenue for further understanding the ERCD mechanism of Co-N x -C catalysts.
研究领域:
材料科学
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电催化
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理论计算
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2023
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IF 6.7
Yuxiang Mao,Jun Cheng,Hao Guo,Lei Qian,Jiacan Tu,Weijuan Yang
To enhance catalytic acid-base sites in ZIFs and efficiently promote conversion of microalgal lipids, a bifunctional catalyst with single-atom Fe-N 4 sites and Fe nanoparticles (NPs) was synthesized by pyrolyzing Fe-doped ZIF-8. Compared with ZIF precursors, Fe nanoparticles and coordinated Fe ions in Fe-N 4 sites enhanced Lewis acidity, while increased uncoordinated N atoms enhanced Lewis basicity. Therefore, the acidity of Fe-NC increased from 0.473 to 1.845 mmol/g, while basicity increased from 0.172 to 0.439 mmol/g. DFT calculations showed that the adsorption energies of acetic acid on the Fe–N 4 and Fe NP were −0.536 eV and −0.397 eV, respectively, exceeding that (-0.190 eV) on the Zn–N 4 site. The energy barriers for rate-determining steps over the Fe-N 4 and Fe NP were + 0.32 eV and + 0.21 eV, respectively, which were lower than that (+1.01 eV) over the Zn-N 4 site. The maximum biodiesel yield reached 98.3% over Fe-NC catalyst, higher than that (84.5%) over ZIF-8 catalyst.
研究领域:
催化化学
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能源材料
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生物技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2022
·Vol. 10
·期 17
·9435-9444
·
IF 14.511
Qingshan Zhao,Wanxin Ni,Xiaojie Tan,Fengliang Cao,Tengfei Liu,Hao Huang,Zhinian Cheng,Yiwen Li,Shuwei He,Hui Ning,Mingbo Wu
Selective hydrogenation of nitroarenes to corresponding anilines is one of the most important processes in the chemical industry, which still suffers from lack of efficient catalysts with both high activity and selectivity. Herein, a reinforced single-atom Co catalyst (Co–N–CNS–Th) was rationally fabricated through a novel “Trojan horse” strategy for boosting selective hydrogenation of nitroarenes. The cobalt salt precursor is confined in a mixed molten salt (KCl + CaCl2) via recrystallization and gradually released when reaching the melting point, which can efficiently achieve atomic Co–N4 moieties accommodated in micropore defect-rich carbon nanosheets. The prepared Co–N–CNS–Th catalyst showed superior hydrogenation activity and selectivity (yield of >99%; overall TOF of 169.8 h−1) towards a series of functionalized nitroarenes under mild reaction conditions, as well as remarkable stability and reusability, standing out among the reported cobalt-based catalysts. The experimental results and DFT calculations reveal that the robust atomically dispersed Co–N4 active sites located near the edge of micropore defects can significantly accelerate the adsorption and activation of hydrogen and nitro groups, accounting for the prominent catalytic performance. This work opens a feasible avenue for the development of advanced single-atom catalysts towards selective hydrogenation of nitroarenes and beyond.
研究领域:
催化化学
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材料科学
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理论计算化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Yanan Shang,Xinning Liu,Yanwei Li,Yue Gao,Baoyu Gao,Xing Xu,Qinyan Yue
The synthesis of a highly efficient and stable single atom catalyst (SAC) for peroxydisulfate (PDS) activation remains a challenge. Herein, a reconstructed iron single atom catalyst (Fe-SAC) with both abundant conjugated π-π sp 2 structured carbon and reactive Fe-N 4 sites was first reported to improve the decomposition of organics in PDS/SACs systems. Enhanced organics adsorption can be achieved by the conjugated π-π sp 2 structured carbon via π-π interaction to decrease the migration distance of reactive species to organic molecules. In addition, PDS tended to be attached onto the Fe-N 4 sites accompanied by the peroxymonosulfate (PMS) generation via S-O breakage of PDS, accelerating the generation of radicals. As a result, organics decomposition via PDS activation by reconstructed Fe-SAC was significantly higher (∼6 times) than the conventional Fe-SAC because of the synergistic effect of the resulting dual reaction sites. This work provides a new strategy to enhance the catalytic performances in PDS/SACs systems.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Guojun Li,Zheng Lian,Qiuqiu Lyu,Chenyu Zhu,Zhinian Liu,Shule Zhang,Qin Zhong
The efficiency of photocatalytic Nitric Oxide(NO) oxidation is limited by the lack of oxygen(O 2 ) active sites and poor charge carrier separation. To address this challenge, we developed a molecular Cobalt Phthalocyanine modified MIL-68(In)–NH 2 photocatalyst with a robust Built-in electric field(BIEF). In the 2 % CoPc-MIN sample, the BIEF strength is increased by 3.54 times and 5.83 times compared to pristine CoPc and MIL-68(In)–NH 2 , respectively. This BIEF facilitates the efficient S-scheme charge transfer, thereby enhancing photogenerated carrier separation. Additionally, the Co-N4(II) sites in CoPc can effectively trap the separated photoexcited electrons in the S-scheme system. In addition, the Co-N4(II) sites can also serve as active sites for O 2 adsorption and activation, promoting the generation of superoxide radical ( O 2 – ), thereby driving the direct conversion of NO to nitrate(NO 3 – ). Consequently, the 2 % CoPc-MIN sample exhibits a remarkable photocatalytic NO removal efficiency of 79.37 % while effectively suppressing the formation of harmful by-product nitrogen dioxide(NO 2 ) to below 3.5 ppb. This study provides a feasible strategy for designing high-efficiency O 2 activation photocatalysts for NO oxidation.
研究领域:
环境科学
·
材料科学
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光催化
✓ 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）