ATMOSPHERIC ENVIRONMENT
·
2024
·
IF 4.2
Cici Fan,Huijie Yan,Weigang Wang,Zheng Sun,Maofa Ge
Aldehydes are one of the most important oxygenated volatile organic compounds in the atmosphere, contributing to atmospheric radicals such as HO 2 and RO 2 , which play a pivotal role in atmospheric chemistry and the oxidative capacity of the atmosphere. The kinetics, gas-phase products, and SOA formation of pentanal and n-hexanal initiated by Br atoms were studied in this work. The reaction rate constants of n-pentanal and n-hexanal reacting with Br atoms were determined to be (1.77 ± 0.25) × 10 −11 cm 3 molecule −1 s −1 and (2.07 ± 0.29) × 10 −11 cm 3 molecule −1 s −1 at 298 K and 760 Torr, respectively. Key gas-phase products, including smaller aldehydes, carboxylic acids, and alcohols, are known to contribute to atmospheric reactivity and have potential implications for air quality by promoting the formation of secondary pollutants and influencing the oxidative capacity of the atmosphere. The SOA yields were (5.24 ± 0.10)% and (6.00 ± 1.20)% for n-pentanal and n-hexanal, respectively, higher than the SOA yields of the aldehydes reaction initiated by OH radicals. The higher SOA yields observed from Br atoms oxidation compared to OH radical oxidation highlight the necessity to re-evaluate the role of halogen chemistry in atmospheric processes, particularly in regions where halogen compounds are prevalent. This research enhances our understanding of the atmospheric fate of aldehydes and highlights the importance of considering halogen-driven oxidation pathways in atmospheric models.
研究领域:
环境科学
·
大气化学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2013
·
IF 4.593
Lingyun Dong,Shilie Pan,Ying Wang,Hongwei Yu,Xiaoyu Dong,Shujuan Han,Min Zhang
The structures of two new lead-containing oxyborate bromines, Pb2(O4Pb8)(BO3)3Br3 (1) and Pb2(O8Pb12)(BO3)2Br6 (2), are determined by single-crystal X-ray diffraction for the first time. Both of them crystallize in the space group C2/c of the monoclinic crystal system. Although the two compounds have the same type of fundmental building units (FBUs), the OPb4 anion-centered tetrahedra and BO3 triangles, they exhibit different connection modes. Compound 1 consists of single ∞1[OPb2] chains, while compound 2 possesses ∞1[O2Pb3] ribbons. Interestingly, large Br atoms profoundly influence the conformation of polyions based on the OPb4 anion-centered tetrahedra, resulting in single ∞1[OPb2] chains linked up by finite zweier chains with four OPb4 tetrahedra via the opposite edges in compound 1 and ∞1[O2Pb3] ribbons with sequential condensation of OPb2 chains in compound 2. A detailed description of the effect of large Br atoms on the conformation of polyions is discussed. IR spectroscopy, UV–vis–NIR diffuse reflectance spectroscopy, and thermal analysis are also performed on the reported materials.
研究领域:
材料化学
·
晶体学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Ying Zhang,Linlin Zang,Shuting Zhao,Weipeng Cheng,Long Zhang,Liguo Sun
Covalent organic frameworks (COFs) have great potential for photocatalytic CO 2 reduction, owing to their adjustable structures, porous characteristics, and highly ordered nature. However, poor light absorption, fast recombination of photogenerated electron-hole pairs, and suboptimal coordination conditions have contributed to the hindered efficiency and selectivity observed in photocatalytic CO 2 reduction processes. In this work, the integration of bromine (Br) atoms into COFs was achieved through the synthesis process involving nickel (II) tetraaminophthalocyanine (NiTAPc) and 3,6-dibromopyromellitic dianhydride (BPMDA) using a solvothermal approach. The coupling of a porous framework structure alongside the incorporation of Br atoms yields a significant enhancement in photoelectric properties compared to bromine-free COFs. Meanwhile, X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations revealed that the introduction of Br atoms can facilitate the adjustment of the electron configuration around the phthalocyanine unit and diminish the required energy for the photocatalytic reaction. When subjected to visible light irradiation, the NiTAPc-BPMDA COF showcased a CO yield of 148.25 μmol g −1 over a 5-hour period, accompanied by an impressive selectivity of 98%. This work highlights the collaborative influence of phthalocyanines and Br atoms within COF-based photocatalysts, offering an alternative approach for designing and constructing high-performance photocatalysts with elevated yield and selectivity. The synergistic role of phthalocyanines and Br atoms within the COF-based photocatalysts provides an alternative strategy for photocatalysts with high yield and selectivity in the future.
研究领域:
材料科学
·
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nature Communications
·
2019
·Vol. 10
·期 1
·1-8
·
IF 11.878
Cui Bin-Bin,Han Ying,Huang Bolong,Zhao Yizhou,Wu Xianxin,Liu Lang,Cao Guangyue,Du Qin,Liu Na,Zou Wei,Sun Mingzi,Wang Lin,Liu Xinfeng,Wang Jianpu,Zhou Huanping,Chen Qi
As one of next-generation semiconductors, hybrid halide perovskites with tailorable optoelectronic properties are promising for photovoltaics, lighting, and displaying. This tunability lies on variable crystal structures, wherein the spatial arrangement of halide octahedra is essential to determine the assembly behavior and materials properties. Herein, we report to manipulate their assembling behavior and crystal dimensionality by locally collective hydrogen bonding effects. Specifically, a unique urea-amide cation is employed to form corrugated 1D crystals by interacting with bromide atoms in lead octahedra via multiple hydrogen bonds. Further tuning the stoichiometry, cations are bonded with water molecules to create a larger spacer that isolates individual lead bromide octahedra. It leads to zero-dimension (0D) single crystals, which exhibit broadband ‘warm’ white emission with photoluminescence quantum efficiency 5 times higher than 1D counterpart. This work suggests a feasible strategy to modulate the connectivity of octahedra and consequent crystal dimensionality for the enhancement of their optoelectronic properties.
研究领域:
材料科学
·
光电学
·
半导体
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）