超音波輔助化學水浴法製備 Ag-In-S 薄膜

Preparation of Ag-In-S Thin Films by Using Ultrasonic Chemical Bath Deposition and Their Photoelectrochemical Properties

黃銘賢(Ming-Hsien Huang)

指導教授 ： 李元堯 ； 李岱洲

國立中正大學/工學院/化學工程學系/碩士(2012年)

摘要

本研究主要探討以超音波輔助化學水浴法 (Ultrasonic Chemical Bath Deposition, UCBD) 以及化學水浴法 (Chemical Bath Deposition, CBD) ，藉由控制前驅物 [Ag]/[In] 金屬離子的莫耳數比，製備出三成分 I-III-VI 族多晶型 AgIn5S8 、混相 AgIn5S8/AgInS2 與多晶型 AgInS2 薄膜結構。以氙燈照射並施加偏壓 1 伏特(vs. SCE)的條件下，觀察其光電流值。由光電流量測的結果得知，以化學水浴法與超音波輔助化學水浴法製備的 AgInS2 具有較佳的光電流值 1.38 與 1.22 mA/cm2，而超音波輔助化學水浴法 [Ag]/[In] 莫耳數比為 4 的混相 AgIn5S8/AgInS2 有較大光電流值 1.63 mA/cm2，除了增加鍍膜次數來避免基材裸露的問題，我們以超音波輔助水浴法的方式，增加薄膜的緻密度也可有效避免基材裸露與暗電流上升問題，另外也提升其光電流值，後續希望藉由 IMPS/IMVS 分析技術，得知其電洞收集係數擴散係數、電子(洞)存活時間、電子(洞)擴散長度、有效吸收係數及等等，藉由此技術分析以不同膜厚，找出具有最大光電流之最佳膜厚參數。

關鍵字

超音波輔助化學水浴法 ； 銀-銦-硫

並列摘要

In this study, we have prepared several photocatalyst thin films by using ultrasonic chemical bath deposition (UCBD) and chemical bath deposition (CBD). By controlling [Ag]/[In] molar ratios in the precursors, we can obtain a single phase AgIn5S8, mixtures of AgIn5S8 and AgInS2 and a single phase AgInS2 thin films.
Photoelectrochemical property, typically photocurrent density was measured under Xe lamp irradiation. The intensity of the light was set at 100 mW/cm2. The linear sweep voltammetry data shows that CBD-AgInS2 and UCBD-AgInS2 thin films have photocurrent densities of 1.38 and 1.22 mA/cm2 under a bias of 1 V vs. SCE, respectively. Moreover, the UCBD- thin film, mixed phase of AgIn5S8 and AgInS2 has the highest photocurrent density of 1.63 mA/cm2 under a bias of 1 V vs. SCE.
Although increasing coating layers can avoid exposure of ITO-coated glass substrate, UCBD method generates a denser thin film that can effectively decrease the dark current, or leakage current, leading to an enhancement of photoelectrochemical activity. The further analytical measurements based on IMPS and IMVS will provide more physical properties of the materials, such as charge carrier collection efficiency, diffusivity, carrier lifetime, diffusion length, and etc. These data can guide us to fabricate a more efficient Ag-In-S thin film.

並列關鍵字

Ultrasonic Chemical Bath Deposition ； Ag-In-S

參考文獻

1. Fujishima, A.; Honda, K., Electrochemical Photolysis of Water at a Semiconductor Electrode. Nature 1972, 238, 37-39.

2. Tsuji, I.; Kato, H.; Kudo, A., Visible-Light-Induced H2 Evolution from an Aqueous Solution Containing Sulfide and Sulfite over a ZnS–CuInS2–AgInS2 Solid-Solution Photocatalyst. Angewandte Chemie 2005, 44, 3565-3568.

3. Hattori, K.; Akamatsu, K., Electrical properties of polycrystalline chalcopyrite AgInS2& films. Journal of Applied Physics 1992, 71, 3414-3418.

4. Michael, G., Photoelectrochemical cells. Nature 2001, 414, 338-344.

5. Gorska, M.;Beaulieu, R.;Loferski, J. J.;Roessler, B., Spray pyrolysis of silver indium sulfides. Thin Solid Films 1980, 67, 341-345.