Compared with traditional the Haber-Bosch process, photocatalytic ammonia production has attracted a considerable attention due to its advantages of low energy consumption and sustainability. In this work, we mainly study the photocatalytic nitrogen reduction reaction (NRR) on MoO·0.55HO and α-MoO. Structure analysis shows that compared to α-MoO, the [MoO] octahedrons in MoO·0.55HO obviously distort (Jahn-Teller distortion), leading to the formation of Lewis acid active sites that favors the adsorption and activation of N. X-ray photoelectron spectroscopy (XPS) further confirms the formation of more Mo as Lewis acid active sites in MoO·0.55HO. Transient photocurrent, photoluminescence and electrochemical impedance spectra (EIS) confirmed that MoO·0.55HO has a higher charge separation and transfer efficiency than α-MoO. Density functional theory (DFT) calculation further confirmed that the N adsorption on MoO·0.55HO is more favorable thermodynamically than that on α-MoO. As a result, under visible light irradiation (λ ≥ 400 nm) for 60 min, an ammonia production rate of 88.6 μmol·g was achieved on MoO·0.55HO, which is about 4.6 times higher than that on α-MoO. In comparison to other photocatalysts, MoO·0.55HO exhibits an excellent photocatalytic NRR activity under visible light irradiation without using sacrificial agent. This work offers a new fundamental understanding to photocatalytic NRR from the viewpoint of crystal fine structure, which benefits designing efficient photocatalysts.
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http://dx.doi.org/10.1016/j.jcis.2023.06.191 | DOI Listing |
Angew Chem Int Ed Engl
January 2025
Fuzhou University, Chemistry, 523 Gongye Rd, Gulou, 350000, Fuzhou, CHINA.
Conjugated polymers, represented by polymeric carbon nitrides (PCNs), have risen to prominence as new-generation photocatalysts for overall water splitting (OWS). Despite considerable efforts, achieving highly crystalline PCNs with minimal structural defects remains a great challenge, and it is also difficult to examine the exact impact of complex defect states on OWS process, which largely limits their quantum efficiency. Herein, we devise a 'in-situ salt flux' assisted copolymerization protocol by using nitrogen-rich and nitrogen-deficient monomers to precisely manipulate the structural defects of poly (triazine imide) (PTI) single crystals.
View Article and Find Full Text PDFCarbohydr Polym
March 2025
School of Environmental and Architecture, University of Shanghai for Science and Technology, Shanghai 200093, China. Electronic address:
Carbon dots (CDs) mediated g-CN (CN) is a promising visible-light-driven semiconductor in catalyzing peroxymonosulfate (PMS) for aqueous contaminants remediation. However, the poor dispersibility of powered catalyst and its challenging recyclability impede their broader application. Herein, we embedded FeN bridge within the g-CN framework and immobilized g-CN gel beads (CA/FNCCN) through a 3D cross-linking process with sodium alginate.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
University of Science and Technology of China, Chemistry, Jinzhai Road 96, 230026, Hefei, CHINA.
Solar-driven CO2 reduction to ethanol is extremely challenging due to the limited efficiency of charge separation, sluggish kinetics of C-C coupling, and unfavorable formation of oxygenate intermediates. Here, we elaborately design a red polymer carbon nitride (RPCN) consisting of S-N and Cu-N4 dual active sites (Cu/S-RPCN) to address this challenge, which achieves an impressive ethanol evolution rate of 50.4 µmol g-1 h-1 with 99.
View Article and Find Full Text PDFJ Fluoresc
January 2025
Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Al-Azhar University, Assiut branch, Assiut, 71524, Egypt.
Nat Commun
January 2025
Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 200032, Shanghai, China.
Considering the unique electronic properties of the CF and the CN groups, the CFCN group has significant potential in drug and agrochemical development, as well as material sciences. However, incorporating a CFCN group remains a considerable challenge. In this work, we disclose a use of bromodifluoroacetonitrile (BrCFCN), a cost-effective and readily available reagent, as a radical source for cyanodifluoromethylation of alkyl alkenes, aryl alkenes, alkynes, and (hetero)arenes under photocatalytic conditions.
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