Molecular Catalysis
·
2024
·
IF 3.9
Zheng Zhou,Meng Miao,Wenzhi Li,Jingting Jin,Liqun Wang,Lulu Zhang,Liang Yuan
The selective conversion of methane is a significant but difficult challenge. We reported a CuFe bimetallic catalyst supported by g-C 3 N 4 for the catalytic oxidation of methane to oxygenated C1 products. Using H 2 O 2 as the oxidant, Cu 0.4 Fe 0.3 -C 3 N 4 catalyst had a C1 yield of 8231 μmol·g cat −1 · h −1 at 70 °C, and 1 H NMR results showed that almost all of the liquid phase products were target C1 products. The methanol selectivity on CuFe-C 3 N 4 was 44.5 %, comparing with 20.2 % methanol selectivity on Cu-C 3 N 4 . The formation of a Cu-O-Fe site on the CuFe-C 3 N 4 was confirmed by in situ DRIFTS and 57 Fe Mössbauer spectroscopy. This Cu-O-Fe site was responsible for the improved catalyst performance. DFT calculations illustrated that at the Cu-O-Fe site, H 2 O 2 dissociated into two ·OH radicals instead of ·H and ·OOH radicals as it did at the Cu-O-Cu site. The ·OH radicals combined with the ·CH 3 radicals from the CH 4 molecules to form methanol. These findings provided valuable insights into the rational design of active sites on carbon nitride materials.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Wen Li,Kuncan Wang,Junjie Huang,Xiao Liu,Dun Fu,Jiale Huang,Qingbiao Li,Guowu Zhan
Metal–organic frameworks have been exploited as excellent solid precursors and templates for the preparation integrated nanocatalysts with multicomponent and hierarchical structures. Herein, a novel synthetic protocol has been developed to fabricate versatile Zr-based solid solutions (such as ZnO–ZrO2, Co3O4–ZrO2, and CuO–ZrO2) via pyrolysis of Schiff base-modified UiO-66 octahedrons (size <100 nm), which were then utilized as efficient catalysts for CO2 hydrogenation. The Schiff base serves as an effective bridge to dope secondary metal ions into UiO-66 frameworks with controlled amounts of 0.13–8.8 wt %, which are initially hard to achieve. Interestingly, by simply changing the loading metal ions, the selectivity of C1 hydrogenation products can be facilely tuned. For instance, the maximum CO2 conversion of ZnO–ZrO2, Co3O4–ZrO2, and CuO–ZrO2 solid solutions were 5.8, 11.4, and 22.5%, with the main product selectivity of 70% CH3OH, 92.5% CH4, and 86.7% CO, respectively. Moreover, in situ diffuse reflectance infrared Fourier transform spectra characterization reveals that the significant difference in C1 product selectivity is mainly determined by the balance of *HCOO, *CH3O, and *CO intermediate species over the Zr-based solid solutions.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Yingxue Sun,Shuai Liu,Huaiqiu Chang,Jianjun Liu,Lingyu Piao
The efficient conversion of methane (CH4) to high-value-added chemicals using a photocatalyst at room temperature and pressure faces great challenges compared to harsh reaction conditions. However, achieving this efficient conversion would yield substantial cost advantages and hold immense potential for development. Here, we demonstrate the enhanced photocatalytic conversion efficiency of CH4 at room temperature and pressure conditions without requiring any oxidant through the construction of a bimetal Ag–Cu-loaded brookite TiO2 photocatalyst. The C1 products were ultimately obtained with 100% selectivity and a yield of 936 μmol·g–1·h–1. The performance exceeds that of similar research by tens of times. The high selectivity of this system is attributed to the optimal number of ·OH, which strikes a balance between excess and deficiency. Ag effectively enhances electron transport in the photocatalytic reaction process on a dual active site photocatalyst, while Cu significantly improves the selectivity of the C1 products. In this system, the hydroxyl radical (·OH) activates CH4 to generate the methyl radical (·CH3), which then binds with the lattice oxygen of TiO2, breaking the Ti–O bond and resulting in the formation of *OCH3. The *OCH3 undergoes further conversion to CH3OH, which is subsequently oxidized to HCHO by ·OH. This work presents a cost-effective and highly efficient approach for directly oxidizing CH4 into valuable chemicals, ensuring superior selectivity.
研究领域:
化学工程
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Green Energy & Environment
·
2023
·
IF 13.3
Liu Han,Cheng-wei Wang,Shan-shan Luo,Ying-tang Zhou,Bing Li,Ming Liu
Employing crystal facets to regulate the catalytic properties in electrocatalytic carbon dioxide reduction reaction (eCO 2 RR) has been well demonstrated on electrocatalysts containing single metals but rarely explored for bimetallic systems. Here, we synthesize ZnSn(OH) 6 (ZSO) microcrystals (MCs) with distinct facets and investigate the facet effects in eCO 2 RR. Electrochemical studies and in situ Fourier Transform Infrared Spectroscopy (in situ-FTIR) reveal that ZSO MCs produce mainly C1 products of HCOOH and CO. The {111} facet of the ZSO MCS exhibits higher selectivity and faradaic efficiency (FE) than that of the {100} facet over a wide range of potentials (−0.9 V ∼ −1.3 V versus RHE). Density Functional Theory (DFT) calculations elucidate that the {111} facet is favorable to the adsorption/activation of CO 2 molecules, the formation of intermediate in the rate-determining step, and the desorption of C1 products of CO and HCOOH molecules.
研究领域:
电化学
·
材料科学
·
催化
·
表面科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）