ã€Chinese instrument network instrument research and development】 Recently, Huang Xingjiu research team of Institute of Intelligent Intelligence, Chinese Academy of Sciences and Prof. Zhang Lizhi of Huazhong Normal University cooperated to study X-ray photoelectron spectroscopy (XPS) combined with extended X-ray absorption fine structure spectrum (EXAFS). The active Fe(II) on the surface of dumbbell-shaped Au/Fe3O4 nanoparticles participates in the redox reaction of the analytes in the Fe(II)/Fe(III) cyclic form, thereby enhancing the detection mechanism of electrochemical analysis behavior.
Detection diagram
Iron-based metal oxide micro/nanostructure materials have received extensive attention due to their unique catalytic, adsorption and magnetic properties, and they have also been widely used in electrochemical analysis of heavy metal ions. For a long time, electrochemical analysis has been aimed at pursuing high sensitivity and low detection limit, and the nano-enhancement mechanism therein is not clear, especially with regard to the special excellent performance of small-sized nanoparticles. The study of the mechanism of revealing the differences in size and size of nanoparticles is very advantageous for the development of new nanomaterials for the detection of heavy metal ions in highly sensitive water environments.
In the earlier work of the research group, the researchers used the Fe3O4 nanoparticles for the excellent adsorption of As (III) and the good catalytic performance of Au to achieve Fe3O4-ionic liquid composites and Au@ Fe3O4 (Fe3O4: 400 nm). Sensitive detection of As(III) (Anal. Chem. 2013, 85, 2673−2680; Anal. Chem. 2016, 88, 1154−1161). On this basis, the researchers prepared a small-sized dumbbell-shaped Au/Fe3O4 (Fe3O4: 10 nm) to further enhance the electrochemical response of the electrode to As(III).
More importantly, the XPS study found that the Fe(II) on the surface of dumbbell-shaped Au/Fe3O4 nanoparticles has a very high activity and can directly reduce As(III) to As(0). Excellent redox activity was not found on large-sized Fe3O4 (400 nm). The change of valence and content of As(III) and Fe(II) in the electrochemical detection process by XPS analysis proves that the surface active Fe(II) is a Fe(II)/Fe(III) cycle with As(III) In the redox reaction, the detection sensitivity of As(III) is further improved.
In addition, combining the EXAFS technology to study the material structure difference of two different sizes of Fe3O4 (10 and 400 nm), it was confirmed that the surface of the small-sized Fe3O4 has a large number of defects, and the Au-Fe3O4 nanoparticles formed by the Au-embedded dumbbell The disorder of Fe-O and Fe-Fe bonds on Fe3O4 surface is further increased. This structural defect and disorder is of great significance for the improvement of Fe(II) activity on the surface of Fe3O4, and is also better than 10 nm Fe3O4. The root cause of 400 nm Fe3O4.
This work utilizes the Fe(II) surface activity of small-sized Fe3O4 to improve the electrochemical performance and reveals that the surface Fe(II)/Fe(III) cyclic enhancement mechanism has a uniquely sensitive interface for realizing the analysis and detection of heavy metal ions. Very good guidance.
The research work was supported by the National Natural Science Foundation of China, the Innovation Crossing Team of the Chinese Academy of Sciences, the Dean’s Fund of Hefei Institute of Material Sciences, and the Shanghai Synchrotron Radiation Facility (BL14W1 Line Station).
(Original title: Smart discovered the mechanism of electrochemical analysis of Fe(II)/Fe(III) cycling enhancement on nanoscale iron oxides.)
Dibenzoyl Peroxide Powder
Benzoyl peroxide, also known as Dibenzoyl peroxide, commonly known as Initiator BPO,It is a strong oxidant, used as a monomer polymerization initiator for polyvinyl chloride, unsaturated polyesters, polyacrylates, etc., as a crosslinking agent for polyethylene, and as a rubber vulcanizing agent.
Benzoyl peroxide is an oxidizer, which is principally used as in the production of polymers.
As a bleach, it has been used as a medication and a water disinfectant.In specialized contexts, the name may be abbreviated as BPO.
As a medication, benzoyl peroxide is mostly used to treat acne, either alone or in combination with other treatments.Some versions are sold mixed with antibiotics such as clindamycin. t is also used in dentistry for teeth whitening.
Benzoyl peroxide is also used in the plastics industry and for bleaching flour, hair, and textiles.It is also used to remove stubborn stains from dolls and other plastic toys, although some users have claimed that the product has unwanted long-term effects of discolouring the item.
Dibenzoyl Peroxide Powder,Bpo Dibenzoyl Peroxide Powder,75%Dibenzoyl Peroxide Powder,50%Dibenzoyl Peroxide Powder
Jiangxi Zhewei Material Technology Co.,Ltd , https://www.jxzwchem.com
