CHEMICAL ENGINEERING JOURNAL
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2021
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IF 13.273
Yan Gu,Tiefeng Xu,Xiufang Chen,Wenxing Chen,Wangyang Lu
Single-atom catalysts (SACs) have become an attractive concept in heterogeneous catalysis because of its high activity, selectivity and maximized utilization efficiency. However, constructing a high-loading SACs through conventional pyrolysis methods remains a challenge, because metal precursors usually have low thermal stability and the decrease of particle size will lead to an increase of surface energy. Herein, we used dicyandiamide to tailor the metatungstate and fix the W atoms during the thermal polymerization process, finally obtained a new kind of W-SAC (single W atoms anchored on graphitic carbon nitride, named as W-CN) with a high-loading of 11.16 wt% and a unique O, N coordination. The electrospray ionization high-definition mass spectrometry (ESI-HDMS) revealed that single W atoms were introduced into graphitic carbon nitride via the polycondense of W-containing dicyandiamide intermediate. The unique atomically dispersed N-W-O 3 moieties, which promoted the separation efficiency of photogenerated electron-hole pairs, were identified by Aberration-corrected scanning transmission electron microscopy (AC-TEM), X-ray photoelectron spectroscopy (XPS), X-ray absorption fine structure spectroscopy (XAFS) and Density functional theory (DFT) calculation. Moreover, compared to pure CN, the W-CN exhibited an enhanced catalytic performance for the oxidation of carbamazepine (CBZ) under solar light irradiation. The experiment results revealed that photogenerated holes (h + ), superoxide radicals (•O 2 − ), and singlet oxygen ( 1 O 2 ) were the predominant active species and played an important role in eliminating emerging contaminants. This work paves a facile and efficient path toward high-loading SAC, and opens new insight into tracking SAC structure evolution.
研究领域:
化学
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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
APPLIED CATALYSIS B-ENVIRONMENTAL
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2023
·
IF 22.1
Kai Song,Huilin Hou,Dongdong Zhang,Fang He,Weiyou Yang
Single-atomic catalysts (SACs) have been emerging as one of potential candidates in catalysts, owing to their unique merits with extremely high specific surface area as well as remarkably exposed active sites. Herein, we develop an in-situ gas-phase cation exchange strategy for engineering single-atomic Co on the surface of TiO 2 photoanode toward solar water splitting. It is verified that the atomically-dispersed Co with Co-O coordination could optimize the surface electronic structures, enhance the light absorption, promote the photoinduced charge transfer, lower the reaction barrier and accelerate the reaction kinetics, which consequently enable the overall improved photoelectrochemical (PEC) behaviors for photoanodes. As a proof of concept, the as-constructed TiO 2 -based photoanodes deliver robust stability up to 100 h and a photocurrent density up to 1.47 mA cm −2 at 1.23 V vs. RHE, which are superior to those of pristine TiO 2 , representing their significance for potential applications.
研究领域:
材料科学
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太阳能转换
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2020
·Vol. 8
·期 9
·4807-4815
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IF 11.301
Ying Gu,Aiping Wu,Lei Wang,Dongxu Wang,Haijing Yan,Peng Yu,Ying Xie,Chungui Tian,Fanfei Sun,Honggang Fu
Single-atom catalysts (SACs) have been promising in various catalytic fields, but the controllable synthesis of SACs with high stability remains challenging. Here, we show a robust strategy toward the fabrication of highly efficient and stable SACs based on the “competitive occupancy” of two metal (M) species on graphene oxide (GO). The abundant M1 (Ti) species predominantly occupy more groups of GO, thereby leaving a tiny number of groups in the gaps of the M1 species to combine with M2 (Co2+, etc.) species. Consequently, this guarantees the formation of Co–N4 SACs embedded in 2D TiN/rGO sheets during nitridation. Further, TiN can act as a “spacer” to prevent Co–N4 from aggregation, thereby improving catalyst stability. Co–N4/TiN–rGO exhibits outstanding catalytic performance for the fast conversion of highly concentrated aromatic nitro compounds (∼0.3–2 mM) into amino compounds and excellent recyclability, which is the best among reported catalysts. In contrast, TiN/rGO has no obvious activity, and Co4N–rGO prepared without Ti competition shows poor activity and stability, which indicates the vital role of Co–N4 and TiN for obtaining the remarkable catalytic ability of Co–N4/TiN–rGO. The reaction mechanism is also proposed based on theoretical calculations. The strategy can be used to design Ni (Fe, Cr, Cu)-based SACs.
研究领域:
材料科学
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催化化学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2019
·Vol. 7
·期 34
·19831-19837
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IF 10.733
Xiang-Wei Guo,Shuang-Ming Chen,Hong-Juan Wang,Zhi-Ming Zhang,Hong Lin,Li Song,Tong-Bu Lu
A series of Mo single-atom catalysts were prepared by calcining a low-cost primary material of urea with various amounts of Na2MoO4·2H2O. Isolated Mo centers are immobilized on in situ formed polymeric carbon nitride via coordinating with two N donors to form two-coordinated MoN2 species. The low-coordinated Mo centers can serve as active sites for N2 chemisorption and activation, achieving high photocatalytic activity for NH3 evolution with a rate of 50.9 μmol gcat−1 h−1 in pure water. In the presence of ethanol as the electron scavenger, the NH3 evolution rate can reach 830 μmol gcat−1 h−1, and the catalyst shows a quantum efficiency of 0.70% at 400 nm. This is the first single-atom catalyst that can drive photocatalytic N2 fixation in pure water with comparable performance to recent reports for photocatalytic N2 reduction. Experimental investigations and density functional theory calculations demonstrate that the coordinatively unsaturated metal center in the single-atom catalysts can strongly adsorb N2via an end-on configuration to elongate the NN bond from 1.11 Å to 1.15 Å, and thus photoexcited electrons can transfer to the weakened NN bond for efficient nitrogen fixation under ambient conditions. These findings provide new insight for solar-driven N2 fixation by atomically dispersing low-coordination metal centers on photoactive supports.
研究领域:
材料科学
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化学
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环境科学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
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2025
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IF 8.2
Fengyu Zhang,Yanping Yang,Qian Wang,Xiaomeng Chen,Lulu Xie,Xintao Li,Dianqing Li,Junting Feng,Xue Duan
When single-atom catalysts are oriented toward practical applications, in addition to balancing the seesaw between activity and selectivity, the capability of thermal management also merits attention. Herein, we proposed a facility approach that, based on active Pd in the state of a single atom, tunes the guest Cu size to simultaneously enhance the effect of d-electron domination and the heat transfer behavior in microregions. Along with the Cu size in an order of magnitude increase, more delocalized electrons were generated and transferred to isolated Pd sites, with the d band center shifting from 1.438 to 1.052 eV, closer to the Fermi level. Simultaneously, more long-range ordered lattices are much favorable for transferring in situ generated thermally phonons with the diffusivity surging from 12.36 to 103.49 mm2/s. The optimized Pd1Cu-SAA catalyst exhibited state-of-the-art performance in acetylene hydrogenation, achieving full conversion at 140 °C, with 95.3% selectivity and good stability in the test period.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACTA PHYSICO-CHIMICA SINICA
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2023
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IF 10.9
Ruijie Zhu,Leilei Kang,Lin Li,Xiaoli Pan,Hua Wang,Yang Su,Guangyi Li,Hongkui Cheng,Rengui Li,Xiao Yan Liu,Aiqin Wang
Catalytic oxidation is a commonly employed technology in the industry for removing volatile organic compounds (VOCs) due to its exceptional efficiency under mild operating conditions. Although supported Pt-based nano-catalysts are recognized widely as one of the most promising and extensively used industrial catalysts for VOC abatement, their practical application, and development are restricted by their exorbitant cost. Single-atom catalyst (SAC) with maximized metal utilization and exclusive electronic character has been explored extensively in various catalytic reactions. However, Pt SAC is usually deemed to be inactive in hydrocarbon oxidation reactions in thermal catalysis, compared with its nanoparticle counterpart. Here, we demonstrate that the WO 3 -TiO 2 supported Pt SAC (Pt 1 /WO 3 -TiO 2 ) exhibits much higher activities than the corresponding nanoparticle catalyst (Pt NP /WO 3 -TiO 2 ) in photo-thermo catalytic oxidation of C 3 H 8 and C 3 H 6 , which represent different kinds of typical VOCs. A key finding is that the activities of Pt 1 /WO 3 -TiO 2 and Pt NP /WO 3 -TiO 2 can be accelerated in photo-thermo catalytic C 3 H 8 oxidation by overcoming oxygen poisoning. Upon the light irradiation, the apparent active energy ( E a ) of the Pt 1 /WO 3 -TiO 2 and Pt NP /WO 3 -TiO 2 decline from 116 to 60 kJ·mol −1 and from 103 to 30 kJ·mol −1 , respectively, substantiating their effectiveness in photo-thermo catalysis. Notably, a substantially higher reaction rate of 3792 μmol∙g Pt −1 ∙s −1 on the Pt 1 /WO 3 -TiO 2 is achieved, which should be a benchmark for C 3 H 8 oxidation. More intriguingly, photo-thermo catalytic C 3 H 6 oxidation on the Pt NP /WO 3 -TiO 2 is prohibited due to the strong adsorption-induced C 3 H 6 poisoning on the Pt nanoparticles, for which the E a of the Pt NP /WO 3 -TiO 2 catalyst for C 3 H 6 oxidation is maintained at approximately 55 kJ·mol −1 , regardless of the light irradiation. In comparison, the C 3 H 6 poisoning on the Pt 1 /WO 3 -TiO 2 can be mitigated by light illumination, where the E a of the Pt 1 /WO 3 -TiO 2 catalyst for C 3 H 6 oxidation dramatically reduced from 49 to 16 kJ·mol −1 , signifying that the high energy barrier of C 3 H 6 oxidation can be mediated by the light. Profiting from the apt affinity between C 3 H 6 and Pt single atoms, the photogenerated electrons accumulated on the Pt single atoms produce repulsive force towards the electron-rich C 3 H 6 molecules, which is conducive to the C 3 H 6 desorption from the Pt 1 /WO 3 -TiO 2 . Therefore, the Pt 1 /WO 3 -TiO 2 exhibits enhanced activity in photo-thermo catalytic C 3 H 6 oxidation. This study exemplifies that the advantages of SAC are not only saving the consumption of precious metals but also discovering new catalytic reactions on the account of the specific electronic characteristic. Download: Download high-res image (85KB) Download: Download full-size image
研究领域:
催化化学
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环境科学
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材料科学
✓ 已验证
DOI
高影响因子
ACS Catalysis
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2021
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IF 13.084
Yiyang Lin,Kang Liu,Kejun Chen,Yan Xu,Hongmei Li,Junhua Hu,Ying-Rui Lu,Ting-Shan Chan,Xiaoqing Qiu,Junwei Fu,Min Liu
Atomically dispersed FeN4 catalysts have been considered as potential materials to replace Pt-based catalysts for the oxygen reduction reaction (ORR), but they often suffer from sluggish O2 activation kinetics due to the symmetrical charge distribution. Herein, we introduce external N, including pyrrolic-N (PN) and graphitic-N (GN), as an electron acceptor near FeN4 to regulate its charge distribution and improve its ORR activity. Theoretical calculations reveal that introduction of PN evokes much enhanced electron redistribution and local electrical field on the Fe site compared with those observed with GN introduction and the pristine one. Synchrotron X-ray absorption spectroscopy and X-ray photoelectron spectroscopy validate the positive charge accumulation of Fe in the FeN4 site induced by introducing PN. Thus, the obtained FeN4-PN exhibits a great performance for ORR in 0.1 M KOH with a remarkable half-wave potential of 0.91 V versus reversible hydrogen electrode, as well as a Tafel slope of 58 mV decade–1. This work provides a guide to improve the catalytic performances of single-atom catalysts by introducing charge-redistribution sites.
研究领域:
材料科学
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催化化学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2025
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IF 7.2
Shujie Liang,Jiaxin Lv,Yishun Wang,Hong Deng
The development of efficient and stable single-atom catalysts (SACs) for CO 2 photoreduction is a persistent challenge. This study reports the successful preparation of SACs by incorporating isolated Ni atoms into carbon nanorods through a low-temperature calcination process using nickel bis(dimethylglyoximate) complexes. These Ni atoms, maintaining their original coordination environments, can facilitate charge separation, and enhance CO 2 adsorption and activation. The optimized catalyst exhibits a CO formation yield of 24.4 µmol with ∼96 % selectivity in high-purity CO 2 , outperforming both the precursor and pure carbon. Additionally, the Ni SACs showed strong catalytic selectivity in diluted CO 2 conditions, with selectivity rates of 82.57 %, 80.35 %, and 61 % at 0.1, 0.05, and 0.01 atm, respectively. This work provides critical insights for designing efficient visible light-responsive CO 2 photoreduction catalysts at the atomic level.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Nature Sustainability
·
2023
·Vol. 6
·期 7
·816-826
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IF 27.6
Lei Xin,Tang Qingyun,Zheng Yongping,Kidkhunthod Pinit,Zhou Xiaolong,Ji Bifa,Tang Yongbing
The electrocatalytic oxygen reduction and evolution of molecular oxygen, known as oxygen electrocatalysis, is one of the most important reactions that are central to a range of energy and environmental technologies. While the current best-performing electrocatalysts remain dominated by precious metals, carbon-based systems provide a compelling alternative owing to their intrinsic sustainability and practical applicability. Here we show a design guided by theoretical calculations that pushes the activity boundaries of carbon electrocatalysts to an unprecedented level. The rationale is that incorporating high-entropy heteroatoms could effectively minimize the local symmetry to destabilize the π-electron network of graphitic carbons and avoid too strong or too weak binding energies for intermediate species of the oxygen reduction reaction and the oxygen evolution reaction. Accordingly, our catalyst embeds five metal single atoms—Fe, Mn, Co, Ni and Cu—and two sources of N, and it exhibits superior bifunctional activities in an alkaline environment that exceed the oxygen reduction reaction and evolution reaction performance of commercial Pt/C and RuO 2 catalysts, respectively. Our work establishes electrocatalyst design principles that could open the door to sustainable solutions for critical green technologies such as fuel cells, batteries and water splitting.
研究领域:
能源材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2024
·
IF 18.5
Yinghui Li,Li Ren,Yingying Yao,Yingyan Zhao,Hao Xu,Zhao Li,Zi Li,Xiaohan dai,Yuhan Tian,Shusheng Cao,Xi Lin,Chongnan Ye,Andreas Züttel,Jianxin Zou
Magnesium hydride (MgH 2 ) is regarded as a promising hydrogen storage material owing to its high gravimetric and volumetric capacity and low cost. However, its large-scale application is hampered by high stability leading to elevated temperature and slow kinetics for ab/desorption. To address these problems, herein, a composite having MgH 2 nanoconfined in a 3D nickel single atoms doped porous carbon (MgH 2 @3D Ni SA-pC) is successfully prepared. Benefitting from the nondestructive synthetic method, strong coupling between MgH 2 and 3D Ni SA-pC is achieved, and the composite exhibits superior hydrogen sorption performances as compared to blank MgH 2 . An onset desorption temperature down to 170 °C and the complete dehydrogenation at 250 °C within 60 min are observed. In particular, thermodynamics of MgH 2 is improved (ΔH ab = 67.9 kJ mol −1 H 2 ) and the heterogenous interfaces are stable during cycling without the formation of an intermetallic Mg 2 Ni catalytic phase. Experimental characterizations and theoretical calculations show that the robust interfaces induce charge transfer from Mg/MgH 2 to Ni SA-pC, which contributes to the weakened Mg─H bonds and thereby improves kinetic and even thermodynamics. Such an interface engineering strategy using single-atom Ni catalyst to simultaneously nano-confine and catalyze MgH 2 paves a way to the design of high-performance hydrogen storage materials.
研究领域:
材料科学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
Nano Research
·
2021
·Vol. 15
·期 4
·3114-3121
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IF 8.897
Li Zhijun,Leng Leipeng,Lu Xiaowen,Zhang Mingyang,Xu Qian,Horton J. Hugh,Zhu Junfa
Atomically dispersed single atom catalysts represent an ideal means of converting less valuable organics into value-added chemicals of interest with high efficiency. Herein, we describe a facile synthetic approach to create defect-containing β -FeOOH doped with isolated palladium atoms that bond covalently to the nearby oxygen and iron atoms. The presence of singly dispersed palladium atoms is confirmed by spherical aberration correction electron microscopy and extended X-ray absorption fine structure measurements. This single palladium atom catalyst manifests outstanding catalytic efficiency (conversion: 99%; selectivity 99%; turnover frequency: 2,440 h −1 ) in the selective hydrogenation of cinnamaldehyde to afford hydrocinnamaldehyde. Experimental measurements and density functional theory (DFT) calculations elucidate the high catalytic activity and the strong metal-support interaction stem from the unique coordination environment of the isolated palladium atoms. These findings may pave the way for the facile construction of single atom catalysts in a defect-mediated strategy for efficient organic transformations in heterogeneous catalysis.
研究领域:
催化化学
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材料科学
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理论化学
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2022
·Vol. 13
·期 1
·1-12
·
IF 17.694
Guo Yalin,Huang Yike,Zeng Bin,Han Bing,AKRI Mohcin,Shi Ming,Zhao Yue,Li Qinghe,Su Yang,Li Lin,Jiang Qike,Cui Yi-Tao,Li Lei,Li Rengui,Qiao Botao,Zhang Tao
Semi-hydrogenation of acetylene in excess ethylene is a key industrial process for ethylene purification. Supported Pd catalysts have attracted most attention due to their superior intrinsic activity but often suffer from low selectivity. Pd single-atom catalysts (SACs) are promising to significantly improve the selectivity, but the activity needs to be improved and the feasible preparation of Pd SACs remains a grand challenge. Here, we report a simple strategy to construct Pd 1 /TiO 2 SACs by selectively encapsulating the co-existed small amount of Pd nanoclusters/nanoparticles based on their different strong metal-support interaction (SMSI) occurrence conditions. In addition, photo-thermo catalysis has been applied to this process where a much-improved catalytic activity was obtained. Detailed characterization combined with DFT calculation suggests that photo-induced electrons transferred from TiO 2 to the adjacent Pd atoms facilitate the activation of acetylene. This work offers an opportunity to develop highly stable Pd SACs for efficient catalytic semi-hydrogenation process.
研究领域:
化学工程
·
催化科学
✓ 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）