Journal of Materials Chemistry A
·
2022
·Vol. 10
·期 44
·23666-23674
·
IF 14.511
Mingna Chu,Yang Li,Ximing Chen,Guangyao Hou,Yan Zhou,Hongjun Kang,Wei Qin,Xiaohong Wu
Solar-driven carbon dioxide (CO2) reduction into valuable chemicals or feedstock is of great significance for the sustainable development of the environment and energy. Herein, we presented a photo-induced reduction method to synthesize catalysts by anchoring Zn single atoms (SAs) on UiO-66-NH2. Impressively, UiO-66-NH2-0.7Zn SAs had excellent performance in converting CO2 to carbon monoxide (CO), which was about a 5-fold improvement compared to pristine UiO-66-NH2 without a photosensitizer or hole sacrificial agent under UV-vis light. The remarkable photocatalytic CO2 reduction performance was attributed to the built-in electric field construction by anchoring highly dispersed Zn SAs on UiO-66-NH2. The built-in electric field could effectively promote the separation of photogenerated charges and activate CO2. Density functional theory (DFT) calculations revealed that low-coordination Zn–N2 sites could dramatically enhance the formation of COOH*, which was the rate-limiting step for CO generation. This study created a new opportunity to develop high-efficiency photocatalysts containing single-atom sites for photocatalytic CO2 reduction.
研究领域:
材料科学
·
环境科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2020
·
IF 7.888
Yingchun Guo,Lei Feng,Changcheng Wu,Xiaomei Wang,Xu Zhang
Rational design and fabrication of metal–organic framework (MOF)-derived ordered hierarchical macro-/meso-/microporous N-doped carbon materials featured with the atomically dispersed metal atoms can effectively enhance their catalytic performance. Herein we develop a template-assisted strategy, namely the confined growth and pyrolysis of single-crystalline zeolite imidazolate framework-8 (ZIF-8) in three-dimensional ordered template voids, to create hierarchical porosity in MOFs-derived N-doped carbon materials. The as-synthesized single-atom Zn on N-doped hierarchically ordered porous carbon polyhedrons (Zn-N-HOPCPs) show integrated Lewis acid (single-atom Zn) and base sites (pyridinic N), high surface area (1128 m 2 ·g −1 ), large pore volume (0.90 cm 3 ·g −1 ), periodically interconnected open windows (~55 nm), highly accessible micro/mesopore channels (0.55, 0.8, 1.2, and 4 nm), and abundant Zn content (5.8 wt%). The hierarchical nanoarchitecture (macro-/meso-/micropores) significantly facilitates mass transfer for bulky-molecule-involved reactions and exposes inside active sites, resulting in satisfactory CO 2 photoconversion under mild conditions. The strategy presented here sheds light on the design and fabrication of various hierarchically ordered porous carbon decorated with atomically dispersed metal atoms for other important applications.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Nano Research
·
2024
·
IF 9.5
Lou Yue,Li Jiao,Li Xiaokun,Zhu Zhenyu,Shi Zhan,Xu Biao
Developing acid/base-resistant and low-price microwave-absorbing materials with lighter weight is highly desired for practical applications in extreme environments. Herein, we demonstrate the successful synthesis of the N-doped porous carbon (NC) material with hierarchical pore structure by the spray pyrolysis method. The large specific surface area (S BET = 707.53 m 2 ·g −1 ) of materials enables multiple scattering of incident electromagnetic waves, and N doping greatly enhances the electrical conductivity of the material. Notably, single-atom Zn can adjust the local electronic structure of adjacent sites such as carbon and nitrogen atoms, induce the center of polarization, and thus change the dielectric and electronic properties of the host material. The porous carbon coating of single-atom Zn avoids the deterioration of electromagnetic parameters caused by the accumulation of magnetic particles under high-temperature pyrolysis. At the same time, they can also be used in various complex environments, such as acidic and basic environments. Ultimately, NC-1000, with high surface area, low density, and good chemical stability, obtained a minimum reflection loss (RL min ) of −50.5 dB and an effective absorption bandwidth (EAB) exceeding 5.1 GHz at the thickness of 1.9 mm. After soaking in the strong acid and base solution, the electromagnetic wave absorption performance of the material decreased by < 15%. Widely available raw materials and a simple preparation scheme are expected to expedite industrial mass production for this novel type of 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
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Zhen-Peng Cui,Le-Xi Zhang,Heng Xu,Yan-Yan Yin,Bo Tang,Li-Jian Bie
Metal-organic frameworks (MOFs) have been proved to be outstanding candidates for humidity sensors, however, pure MOFs are still limited in hysteresis, integration, and intelligence. In this investigation, inspired by a single-site-ion strategy for catalysis, UiO-66-NH 2 is first grafted by 2, 6-DPA (2, 6-dipicolinic acid) molecules (named as U-DPA) and then combined by Zn (II) ions (noted as U-DPA-Zn). Taking advantage of electrolyte and MOF, U-DPA-Zn exhibits significantly enhanced humidity sensing performance than UiO-66-NH 2 and U-DPA. U-DPA-Zn possesses the highest sensitivity (S r = 8.07 × 10 3 ), the best linearity (R 2 = 0.994), the shortest response-recovery time (τ res = 2 s, τ rec = 105 s), the smallest hysteresis (ΔH = 1.81%), as well as good repeatability in a wide relative humidity (RH) range (11%-97%). Thanks to its excellent properties, U-DPA-Zn shows great potential in the field of monitoring human respiration (breath detection) and water evaporation on human skin (finger detection). Additionally, the humidity sensing mechanism is discussed based on complex impedance analysis, revealing the single Zn (II) make giant contribution to MOFs. This work provides an optional material for humidity sensors and further a new strategy to improve the humidity sensitivity of pure MOFs.
研究领域:
材料科学
·
传感技术
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of CO2 Utilization
·
2022
·
IF 8.321
Yingjun Li,Ying Chen,Ya-Li Wan,Ren-Shu Wang,Hu Wang,Yi-Zhu Lei
The development of efficient, cost-effective and heterogeneous catalysts for the valorization of CO 2 to high-value chemicals is of vital importance in reducing CO 2 emissions. Herein, single-atom Zn on bipyridine-based porous organic polymer was successfully fabricated through a facile copolymerization of divinyl-bipyridine and divinyl-benzene monomers , followed by complexation with Zn(OAc) 2 . The prepared materials with different concentrations of bipyridine moieties possessed large surface areas, hierarchical porosity, and strong coordination interaction between Zn(OAc) 2 and the polymer scaffold. Catalytic evaluation demonstrated that the optimal single-atom Zn catalyst displayed extremely high catalytic performance towards the N-formylation of amines with CO 2 and PhSiH 3 . Notably, under mild reaction conditions (30 °C, 1 bar CO 2 ), a Zn loading as low as 0.5 mol‰ was sufficient for 94% yield of N-methylformanilide, with a record-high turnover frequency (TOF) of 376 h −1 compared to previously reported heterogeneous catalysts . Moreover, the solid catalyst could be easily recovered and reused for five cycles. Additionally, various amines could be efficiently transformed into corresponding formamide with moderate to high yields. The present work highlights a facile and cost-effective method for constructing highly efficient and recyclable single-atom metal catalysts for N-formylation of amines with CO 2 .
研究领域:
催化化学
·
材料科学
·
环境化学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2025
·Vol. 21
·期 9
·2410941
·
IF 12.1
Si Zhao,Xudong Chen,David Patrun,Lituo Zheng,Lili Wang,Zhenhai Wen,Sanjay Mathur,Zhensheng Hong
Single-atom materials provide a platform to precisely regulate the electrochemical redox behavior of electrode materials with atomic level. Here, a multifield-regulated sintering route is reported to rapidly prepare single-atom zinc with a very high loading mass of 24.7 wt.% by significantly improved diffusion kinetics and stronger charge transfer between zinc and nitrogen atoms. X-ray absorption near edge structure (XANES) spectra for Zn K-edges during the charge and discharge process verify the stable single-atom zinc structure and the reversible slight reduction and oxidation of Zn sites, which is much different from the previous report of the alloying reaction process. This result suggests atomic Zn acts as an active sites through weak binding with sodium to regulate the Na ion fluxes. Finally, Cu foil coated with a ≈2 µm layer of such material exhibits a high Coulombic efficiency of ≈99.99% up to 1700 cycles at 1 mA h cm −2 . An ultra-low overpotential of 3 mV and an unprecedented life span of over 3200 h in a symmetrical cell is achieved. Due to the very thin coating layer, anode-free sodium battery fabricated by Na 3 V 2 (PO 4 ) 3 cathode displays a prominent energy density of 320 Wh Kg −1 , demonstrating strong potential in practical application.
研究领域:
材料科学
·
电化学
·
储能
·
电池技术
·
纳米材料
✓ 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）