本研究主要目的為發展高溫太陽能吸收膜，發展簡單與低成本的製程在SUS 304 不鏽鋼基板上形成具有高吸收率與低放射率的薄膜。主要是使用高溫爐，讓不鏽鋼在850 ℃、 900 ℃、 950 ℃ 和 1000 ℃不同高溫環境下，持續氧化，使其表面形成Fe2O3吸收膜。除了製程溫度不同之外，製程的另一個變數為氧化時間，不鏽鋼在高溫爐中可氧化時間份別為氧化0.5小時、1.0小時、1.5小時以及2.0小時， 藉此得到實驗製程的最佳參數。進一步將50 nm 、75 nm、 100 nm 及 125 nm 等不同厚度的抗反射層鍍在最佳參數而形成的吸收膜上，藉以提升吸收膜之吸收率。此外，本研究利用掃描式電子顯微鏡 (SEM) 和X光薄膜繞射儀 (XRD) 分析吸收膜的晶體結構及表面結構。研究結果顯示最佳氧化溫度與時間分別為 900 ℃和2.0小時，其吸收率和放射率分別達到0.900和0.35。而在吸收膜上層鍍上100 nm的Al2O3 抗反射層，吸收率將提高至0.936，而放射率微升至0.36。

This present study is aimed at developing a high-temperature solar absorber coating by using a simple and low-cost fabrication technique. By heating SUS 304 stainless steels inside a furnace at different temperatures such as 850 ℃, 900 ℃, 950 ℃, and 1000 ℃, SUS 304 is oxidized and formed an oxide layer of Fe2O3 on the surface. Other than the heating temperature, the period of heating is another important factor that influences the oxidation pretreatment of stainless steels. The SUS 304 is allowed to oxidize for different periods of heating including 0.5 hr, 1.0 hr, 1.5 hr, and 2.0 hr. Based on the results, the optimal temperature and period of heating are determined. The experiment is continued by depositing different thickness of anti-reflective (AR) coating such as 50 nm, 75 nm, 100 nm, and 125 nm on the solar absorbers that are fabricated under the optimal conditions so that the solar absorptivity is enhanced. Besides that, SEM and XRD analyses are conducted to study the crystalline structure and surface morphology of the solar absorbers. The results show that the optimal temperature and period of heating are 900 ℃ and 2.0 hr respectively. The solar absorber fabricated using these optimal parameters display high absorptivity of 0.900 and relatively low emissivity of 0.35. For the solar absorber deposited with a 100 nm-thick Al2O3 thin film AR coating, the absorptivity rises up to 0.936, while the emissivity encounters a minor increment up to 0.36.

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