Detection of Trace Water Based on Electro-oxidation of Molybdenum Disulfide Nanomaterials to Form Molybdenum Oxysulfide.
Di LiuYixuan BianZhiwei ZhuYuanhua ShaoMeixian LiPublished in: ACS applied materials & interfaces (2022)
Molybdenum disulfide nanomaterials nowadays are very popular in electrocatalysis field due to their outstanding catalytic performance toward many electrochemical reactions. However, the electrochemical oxidation reaction of molybdenum disulfide nanomaterials in the range of positive potential has not been studied thoroughly. Herein, we have investigated electro-oxidation of molybdenum disulfide nanomaterials and put forward a new reaction mechanism: molybdenum disulfide nanomaterials are electro-oxidized with water to form molybdenum oxysulfide (MoOS 2 ) and hydrogen ions, leading to the release of hydrogen on the counter electrode. Various characterization methods such as contact angle measurement, scanning electron microscope (SEM), transmission electron microscope (TEM) with energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray absorption near edge structure (XANES) spectroscopy, time-of-flight secondary ion mass spectrometry (ToF-SIMS), and gas chromatography (GC) were applied to attest the doping of oxygen and the generation of hydrogen. Based on this reaction, we constructed a novel ultrasensitive electrochemical sensor for detecting trace water with the minimum detectable content of 0.0010% (v/v) in various organic solvents and ionic liquids, which is comparable to the Karl Fischer titration, but with much simpler reagent.
Keyphrases
- ionic liquid
- high resolution
- mass spectrometry
- gas chromatography
- electron transfer
- gold nanoparticles
- tandem mass spectrometry
- electron microscopy
- label free
- liquid chromatography
- high speed
- molecularly imprinted
- room temperature
- solid state
- solid phase extraction
- high resolution mass spectrometry
- hydrogen peroxide
- dual energy
- capillary electrophoresis
- high performance liquid chromatography
- quantum dots
- gas chromatography mass spectrometry
- visible light
- water soluble
- climate change
- simultaneous determination