CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Min Yang,Xiaohua Ren,Leixin Hu,Weilin Guo,Jinhua Zhan
Advanced oxidation processes (AOPs) based on the activation of persulfate (PS) by minerals have been widely used in environmental remediation. Herein, two goethite materials with different contents of exposed {0 2 1} facet were synthesized and used as the catalysts for PS activation to degrade tetracycline. Results showed that exposed facets significantly affected their catalytic activity. Goethite exposed with more {0 2 1} facet exhibited better catalytic performance. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and electrochemical analysis suggested that the surface Fe(II)/Fe(III) redox cycle, the abundant surface hydroxyl density and the easier generation of active radicals by activating PS were responsible for the excellent catalytic performance of goethite with more {0 2 1} facet exposed. Furthermore, the density functional theory (DFT) calculations further confirmed that {0 2 1} facet was more favorable for the activation of PS than {1 1 0} facet. The electron paramagnetic resonance (EPR) and radical scavenging experiments indicated that both sulfate radicals and hydroxyl radicals participated in the degradation process. This study provides new insights into the PS heterogeneous activation by facet-dependent goethite in environmental catalysis.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
ACS Omega
·
2019
·
IF 2.584
Xiaogang Liu,Guiru Du,Meng Li
Combining the advantages of reactive crystal facets and engineering defects is an encouraging way to address the inherent disadvantages of titanium dioxide (TiO2) nanocrystals. However, revealing the true photoreactivity origin for defective TiO2 with coexposed or predominant exposed anisotropic facets is still highly challenging. Here, the photoreactivity of TiO2 nanocrystals with respectively predominant exposed {001}, {101}, and {100} facets before and after Ti3+ doping under both ultraviolet and visible light was compared systematically. In detail, the photocatalytic H2 production for R-TiO2-001, R-TiO2-101, and R-TiO2-100 increased by a factor of 1.34, 2.65, and 3.39 under UV light and a factor of 8.90, 13.47, and 8.72 under visible light. By contrast, the photocatalytic degradation of methyl orange for R-TiO2-001, R-TiO2-101, and R-TiO2-100 increased by a factor of 3.18, 1.42, and 2.17 under UV light and a factor of 4.03, 2.85, and 1.58 under visible light, respectively. The true photocatalytic activity origin for the obtained photoreduction and photo-oxidation ability is attributed to the exposure of more active sites (under-coordinated 5-fold Ti atoms), the facilitated charge transfer among {001}, {101}, and {100} facets, and the Ti3+ energy state with variable doping levels to extend the visible light response. This work hopefully provides significant insights into the photoreactivity origin of defective TiO2 nanocrystals with anisotropic exposed facets.
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
DOI
PubMed
高影响因子
Catalysis Science & Technology
·
2015
·Vol. 6
·期 6
·1693-1700
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IF 5.426
Zhixin Zhang,Yehong Wang,Min Wang,Jianmin Lu,Chaofeng Zhang,Lihua Li,Jingyang Jiang,Feng Wang
We herein report the oxidative C–C coupling of ketones and primary alcohols to produce α,β-unsaturated ketones in the absence of base additives. This cascade synthetic reaction was conducted at 150 °C in 12 h using a heterogeneous CeO2 catalyst. The conversion of acetophenone reached 74% with 89% selectivity to chalcone. A correlation between the CeO2 crystal plane and catalytic performance is established as the catalytic activities decrease in the sequence of (110) > (111) > (100). Characterization using Raman spectroscopy, CO2 temperature-programmed desorption (CO2-TPD), and in situ active site-capping tests has shown that the unusual catalysis of the CeO2 catalyst is attributed to the coexistence of basic and redox active sites. These sites synergistically catalyze the oxidation of alcohols to aldehydes and the aldol condensation to ketones. Moreover, the CeO2 catalyst can be reused several times after calcination to remove the surface-adsorbed substances.
研究领域:
化学
·
催化科学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Yang Yang,Jiachang Zeng,Yijin Shu,Qingsheng Gao
Noble-metal nanocrystals (NCs) are functional segments of biosensing platforms, but their sensitivity and facet effects are still challenging. Conventional synthesis using surfactants to direct crystal growth unfortunately causes adsorbate–surface hindrance, which not only reduces sensing responses but also leads to misunderstanding on facet-dependence. Herein, we utilize electrochemical CO displacement to remove residual surfactants from facet-engineered Pd NCs, and further investigate the structure–activity relationship on specific facets, for example, {100} in cubes, {111} in octahedrons, and {110} in rhombic dodecahedrons. Along with the remarkably boosted response, facet dependence is obvious for H2O2 sensing after surface cleaning. The Pd{100} shows high sensitivity, low detection limit, and wide applicable concentration range, superior to the {110} and {111}. This can be theoretically interpreted by the befitting *OH binding on {100} and thereby the facilitated H2O2 reduction kinetics. The outstanding selectivity to H2O2 ensures the high efficiency of Pd NCs to measure intracellular H2O2 and recognize different types of cancer cells. Moreover, facet effects are also evidenced in glucose detection, highlighting that this work can provide guidelines to design efficient sensing platforms.
研究领域:
材料科学
·
分析化学
·
生物医学工程
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2016
·Vol. 7
·期 1
·191-199
·
IF 5.287
Zhanwei Ma,Shengli Zhao,Xiaoping Pei,Xumao Xiong,Bin Hu
Three ceria nanocrystals with different morphologies (nanocubes, nanorods, and nanoparticles) were synthesized and used as supports to evaluate the support morphology-dependent ammonia synthesis activity in the structure-sensitive ammonia synthesis reaction. The Ru/r-CeO2 catalyst shows a higher catalytic reaction rate (3830 μmol g−1 h) than that of Ru/c-CeO2 (1289 μmol g−1 h) and Ru/p-CeO2 (529 μmol g−1 h) under the reaction conditions of 400 °C, 1 MPa, and 60 mL min−1. In addition, promoters (Cs, K, and Ba) can effectively enhance the catalytic activity of the catalysts such as 2Cs–Ru/r-CeO2 (14 266 μmol g−1 h) and 2K–Ru/r-CeO2 (11 227 μmol g−1 h). The effect of the morphology of the CeO2 support on the metal–support interaction and catalytic performance of the Ru/CeO2 catalysts can be correlated to the exposed crystal planes and surface composition/electronic structure of the CeO2 support with diverse morphologies.
研究领域:
催化化学
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材料科学
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表面科学
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化学工程
·
无机化学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Aleksei Chalgin,Wenlong Chen,Qian Xiang,Yi Wu,Fan Li,Fenglei Shi,Chengyi Song,Peng Tao,Wen Shang,Jianbo Wu
The urgent need of catalysts with improved performances toward the hydrogen evolution reaction (HER) is still one of the crucial issues for the water splitting electrocatalysis. Herein, we exhibit that the HER activity of the Pd nanocubes could be improved by selecting the appropriately shaped titania nanocrystals as support. In particular, we used Pd nanoparticles with (100)-facet exposed to show that the HER performance of Pd cubes can be improved in both acidic and alkaline electrolyte media when combined on the anatase TiO2 nanocrystals. Furthermore, we have also investigated the facet effect of TiO2 on the performance in detail, which indicated stronger catalytic activity when (001)-TiO2 was used rather than (mix 101/001)-TiO2 and (101)-TiO2. The electron-transfer-induced improvement of HER activity of Pd/TiO2 was assessed by electron energy loss spectroscopy (EELS). Thereafter, the combined support materials with suitable facet exposed can give an additional adjusting path to regulate the HER activities of Pd nanocatalysts, which henceforth can further contribute to a novel way for tuning other catalysts with good electrocatalytic properties.
研究领域:
材料科学
·
电化学
·
纳米技术
·
催化
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）