CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Aimal Khan,Habib Ullah,Qinghong Wu,Wenqiang Gong,Lu Ma,Shuaiqi Zhao,Aihua Xu,Xiaoxia Li
Understanding the role of oxygen vacancies (OVs) in endowing catalytic activity is important for the design of efficient catalysts for advanced oxidation processes. In this study, we prepared MnO catalysts with different amounts of OVs under an atmosphere of H 2 (MnO-H) and N 2 (MnO-N) and investigated their acetaminophen (ACE) degradation efficiency via peroxymonosulfate (PMS) activation. MnO-H exhibited the best degradation performance because of its numerous OVs, compared with that of MnO-N and the commercial MnO. Data analysis revealed that ACE degradation proceeded via electron transfer. Density functional theory calculations confirmed that compared with the other catalysts, MnO-H/PMS with more OVs had higher catalytic activity, higher adsorption energy, lower work function, and higher electron transformation. The MnO-H/PMS system was stable at pH 3.0–9.0 and showed good recyclability. We believe that our findings will provide deeper insights into the role of OVs and encourage the use of less toxic metal oxides as catalysts in the selective degradation of organic pollutants in water bodies.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Advanced Science
·
2018
·Vol. 6
·期 1
·1801182
·
IF 12.441
Zao Wang,Feng Gong,Ling Zhang,Rui Wang,Lei Ji,Qian Liu,Yonglan Luo,Haoran Guo,Yuehui Li,Peng Gao,Xifeng Shi,Baihai Li,Bo Tang,Xuping Sun
NH 3 is a valuable chemical with a wide range of applications, but the conventional Haber–Bosch process for industrial-scale NH 3 production is highly energy-intensive with serious greenhouse gas emission. Electrochemical reduction offers an environmentally benign and sustainable route to convert N 2 to NH 3 at ambient conditions, but its efficiency depends greatly on identifying earth-abundant catalysts with high activity for the N 2 reduction reaction. Here, it is reported that MnO particles act as a highly active catalyst for electrocatalytic hydrogenation of N 2 to NH 3 with excellent selectivity. In 0.1 m Na 2 SO 4 , this catalyst achieves a high Faradaic efficiency up to 8.02% and a NH 3 yield of 1.11 × 10 −10 mol s −1 cm −2 at −0.39 V versus reversible hydrogen electrode, with great electrochemical and structural stability. On the basis of density functional theory calculations, MnO (200) surface has a smaller adsorption energy toward N than that of H with the *N 2 → *N 2 H transformation being the potential-determining step in the nitrogen reduction reaction.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Gangsheng Zhang,Yi Wang,Meng Chen,Jixiang Xu,Lei Wang
In this work, a carbon-doped Co 3 S 4 /CoSO 4 /MnO catalyst (C@CoSOMn) was prepared in this work by using ZIF-67 as the template. The prepared catalyst was used to degrade levofloxacin (LEVO) by activating peroxymonosulfate (PMS). The optimized catalyst could degrade 97.73 % LEVO within 20 min with a rate constant of 0.294 min −1 . The combination of water-soluble CoSO 4 and Co 3 S 4 made more Co sites accessible to PMS for lasting decomposition to produce active species. Moreover, Mn species with low redox potential could promote the regeneration of Co 3+ and the activation of PMS. The doped carbon could facilitate the transfer of electron. Superoxide radicals (⋅O 2 − ), bulk and surface hydroxyl radicals (•OH), surface sulfate radicals (SO 4 •− ), and electron transfer process, especially the singlet oxygen ( 1 O 2 ) were involved in the LEVO degradation. This study sheds light on the synergism between the Co-based sulfide and the Mn oxide in the activation process of PMS, and might prompt the development of other ZIF-67-derived hybrid materials for environmental remediation.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2022
·
IF 14.224
Hafiz Muhammad Adeel Sharif,Muhammad Bilal Asif,Yuwei Wang,Ya-Nan Hou,Bo Yang,Xu Xiao,Changping Li
Iron (Fe)-based catalysts are widely used for taming nitrogen oxides (NO x ) containing flue gas , but the regeneration and long-term reusability remains a concern. The reusability can be acquired by external additives, and resultantly can not only increase the cost but can also add to process complexity as well as secondary pollutants. Herein, a self-sustainable material is designed to regenerate the catalyst for long-term reusability without adding to process complexity. The catalyst is based on reduced graphene-oxide impregnated by Fe 2 O 3 -MnO (rGO@Fe 2 O 3 -MnO; G-F-M) for spontaneous intra electron (e - )-transfer from Mn to Fe. The developed catalyst; G-M-F exhibited 93.7% NO x reduction, which suggests its high catalytic activity . The morphological and structure characterizations confirmed the Fe/Mn loading, contributing to e - -transfer between Mn and Fe due to its conductivity. The synthesized G-F-M showed higher NO x reduction about 2.5 folds, than rGO@Fe 2 O 3 (G-FeO) and rGO@MnO x (G-MnO x ). The performance of G-M-F without and with an electrochemical system was also compared, and the difference was only 5%, which is an evidence of the spontaneous e - transfer between the Mn and Fe-NO x complex. The designed catalyst can be used for a long time without external assistance, and its efficiency was not affected significantly (<3.7%) in the presence of high oxygen contents (8%). The as-prepared G-M-F catalyst has great potential for executing a dual role NOx removal and self-regeneration of catalyst (SRC), promoting a sustainable remediation approach for large-scale applications.
研究领域:
环境科学
·
材料科学
✓ 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）