- 期刊
動電位陽極沉積法製備錳氧化物薄膜及其擬電容行為
Pseudo-capacitive Properties of Manganese Oxide Films as Prepared by Potentiodynamic Anodic Deposition
摘要
超高電容器因具有高穩定性及高比電容值之特性，近年來被作為多項電子產品之備用電源元件而深受各界矚目。錳氧化物是作為超高電容器深具潛力之電極材料。本研究旨在利用動電位陽極沉積法，以不同之沉積速率於醋酸錳溶液中製備出可做為超高電容器電極材料之錳氧化物薄膜電極，該薄膜之化學組成及微觀結構是分別以Raman光譜及FE-SEM鑑定，擬電容行為及比電容值之評估是利用恆電位儀以循環伏安法在0.1M Na_2SO_4、25℃下進行。實驗結果顯示，錳氧化物電極的比電容值及微觀結構深受動電位陽極沉積速率的影響；比電容值隨沉積速率之增加而增加，沉積速率為100mVs^(-1)，比電容值達最高值之219Fg^(-1)，之後比電容值是隨沉積速率之增加（至600mVs^(-1)）而降低。製備的錳氧化物薄膜主要是由三價及四價的錳離子所組成，且具高孔隙度及奈米纖維結構之特性；經過1000圈的循環伏安測試之後，錳氧化物薄膜之比電容值衰退率僅12％，顯示其在長時效使用上具有優異的穩定性。
並列摘要
It is noticeable that a supercapacitor has such a high stability and specific capacitance (SC) that are deemed as most suitable for a backup device for electronic products. Manganese oxide is one of the promising electrode materials for the supercapacitor. This study tried to prepare the manganese oxide films using potentiodynamic anodic deposition under different deposition rates. We used Raman scattering spectra and a field-emission scanning electron microscopy (FE-SEM) to determine the microstructures and chemical compositions of the manganese oxide films. The pseudo-capacitive proper ties of the manganese oxide films were determined by cyclic voltammetry (CV) in the range 0.0-1.0V (vs. SCE) in 0.1M Na_2SO_4 solution at 25℃. The porous and nano fiber structures were obtained for the manganese oxide film deposited at a deposition rate of 100mVs^(-1). Results showed that the SC and micro-structure are highly affected by the deposition rate at the electrode. The pseudo-capacitance has the highest SC of 219 Fg^(-1) and after 1000-cycle tests the SC decay rate is 12%.