碩士 / 國立清華大學 / 化學工程學系 / 102 / In the research area of photocatalytic water splitting for hydrogen production area, there are increasingly more and more research groups placputting their efforts on visible light driven materials. Cadmium sulfide is probably Up to now, the most thoroughly investigateddiscussed visible light driven photocatalystmaterial would be cadmium sulfide. Although cadmium sulfide does possess the ability to produce hydrogen under visible light irradiation, its instability and toxicity are majorstill our concerns. Tin disulfide is an n-type semiconductor which is non-toxic, inexpensive, and chemically stable. Tin disulfide is a visible light driven material since its band gap is onlyranges from 2.2~2.35 eV. According to literaturethe reference, its band structure is also suitable for hydrogen production, which makes ittin disulfide a promising alternative visible light driven photocatalyst to material that might replaces cadmium sulfide.
We use tin(IV) chloride pentahydrate and thioacetamide as theour precursors to synthesizes tin disulfide nanoplates with a hydrothermal process. The productwith platearticle sizes rangesing from 15 to 40 nm. XRD data confirms that they are all products obtained are tin disulfide. TEM images shows that the lamellar structure is composed of more than ten layers in the thickness direction. Tin disulfide obtained at a reaction temperature of 160 oC and reaction time of 12 hours, SnS2-160-12, is shown to be SnS2-160-12, a meso--porous with amaterial, possesses the highlargest specific surface area of which reaches 105.4657〖 m〗^2/g. The band gap, is 2.1 eV, which is determined by UV-visible absorption spectrumspectra, is 2.1 eV. TheOur photocatalytic reactor is with an designed to be inner illumination light source,ed a by 400 W high-pressure mercury lamp. A solution of In order to filter UV light, 1M NaNO2 is usedchosen to be the filter out all lights with wavelengths shorter than 420 nmsolution. Na2S and Na2SO3 serve as theare the sacrificial agents in our system. According to our the results, tin disulfide could produces hydrogen atwith the rate of 287.718 μmol/hr, which is 1.24 times of thate rate of cadmium sulfide.
In additionMoreover, we try to decorate cadmium sulfide nanorods are decorated with tin disulfide nanoparticles to form a heterojunction composite photocatalyst. It is evidentobvious to see from SEM and TEM images that tin disulfidethere are lots of nanoparticles are successfully decorated onto the surfaces of attached on the cadmium sulfide nanorods from the SEM and TEM. With the help of HR-TEM and XPS analyseis, we are certain that the nanoparticles are tin disulfide. These two semiconductor materials would formcreate a staggered heterojunction, enabling and their matching band structures makeimproved charge separation electron-hole pair well separated. Owing to this effect, electron-hole pair recombination isshould be retardedduced, which improvesmakes better the hydrogen production ability of the composite photocatalyst. Sample SnS2-20/CdS-160-12 could produces hydrogen atwith the rate of 432.609 μmol/hr, which is 1.9 times of thate rate of pure cadmium sulfide
| Identifer | oai:union.ndltd.org:TW/102NTHU5063020 |
| Date | January 2014 |
| Creators | Lin, Hsin-Han, 林信翰 |
| Contributors | Lu, Shih-Yuan, 呂世源 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 92 |
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