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大綱
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摘要
近年來因溫室效應造成全球平均溫度逐漸增加，促使人類依賴冷氟空調能源消耗大
幅提升，如何降低能源危機與尋找替代能源相對已逐漸受到重視，開發節能装置是一個有效的方法。電致變色元件具有多項節能優點如低電壓驅動，只需要微小電壓即可操作、具高記憶效應在移除驅動電源後仍可保持原有特、具高隔熱性可效隔絕太陽光所造成的熱效應且有效降低室內空調能源消耗、具高透光率可保持視覺上的視野，應用於電致變色節能窗，可打造零碳建築之環境。相較目前業界電致變色元件通常採用的濺鍍製程(Sputtering)，本研究採用高密度之電弧電漿製程(Arc
Plasma)，其鍍膜速率可大幅度提升，有效減少生產製造的電力消耗進而降低碳排放與成本。此製程具之低碳生產、低能耗、低汙染之優點，符合綠色製造之精神，有助於未來協助產業能源轉型。
一般而言電致變色元件為五層薄膜結構，其中包含導電薄膜層/
電致變色層/電解質
層/離子儲存層/導電薄膜層，傳統上使用三氧化鎢(W03)為電致變色層之陰極材料，氧化鎳(NiO)為離子儲存層之陽極材料，本研究主要探討應用新穎材料二氧化銥(IrO2)做為陽極離子儲存層並以不同氬氧比例之氣體流量備製，再搭配三氧化鎢(W03)為陰極，利用储環伏法分析電化學性質，同時探討其材料結構與光學性質，來提升整體元件光穿透度差、循環壽命與反應時間。研究結果顯示，二氧化銥(IrO2)薄膜具較高的擴散係數值，有助於鋰離子在氧化還原的過程中傳遞較快；同時發現此材料晶粒結構具有絲狀(Filamentary)且互相連結(Interconnected)之特性，擁有較多的內部孔際(Inner
Pore)，可利於鋰離子在傳遞路徑上具更多的孔隙空間，更容易遷入/遷出陽極薄膜表面。由二氧化銥(IrO2)組成的電致變色元件(IrO2-ECD)其光穿透差為公T=50%優於氧化鎳(NiO)組成的電致變色元件
(NiO-ECD) 4T=32%，經過 1000
次循環壽命試驗仍可維持原先初始光穿透率差之96%維持率。進一步研究發現，利用二氧化銥(I102)做為缓衝層 (IO,
buffer layer)於五氧化二釩摻雜鈦(Ti:V205)做為陽極組成之電致變色元件(buffer-ECD)，其光穿透度差可更進一步提升至么T=57%，循環壽命更可維持原先初始光穿透率差之98%維持率。
關鍵宇:電弧電漿製程、濺鍍製程、電致變色元件、二氧化銥、氧化鎳、緩衝層五氧化二釩摻雜鈦
Abstract
In recent years,
Greenhouse Effect is increasingly raising global average temperatures
and leads to the severe problem on air condition massive consumption.
Currently, how to mitigate energy crisis and find alternative energy
are essential issues. One approach is the development of energy saving
device. Electrochromic devices (ECD) are regared as excellent choice
as they
feature low power driving, excellent
memory, effective reversible changing for heat isolation that applied
on smart windows can block solar heat and effectively reduce the
air-condition loading of buildings at indoor. However, ECDs are still
too expensive to be widely used due to the high fabrication cost.
Currently, sputtering is the most common technology for electrode film
preparation. In this work, the electrodes were fabricated using Arc
Plasma (AP) as this process provides an high-density plasma source can
significantly promote deposition rate to reduce power consumption in
the manufacturing process, effectively decrease production cost and
low carbon emission which achieve the concept of "Green Manufacturing
(G.M.) that can replace the available sputtering process for producing
ECDs.
In general, ECD consists of a five-layer structure, TCO/EC/EL/CE/TCO,
including transparent conducting oxide(TCO), electrochromic layer
(EC), electrolyte layer(EL), and counter electrode (CE) and TCO. In
this study, the ion conducting layer of ECDs is investigated. An NiO
film as a counter electrode in ECDs is susceptible to degradation upon
prolonged electrochemical cycling, which leads to an unacceptable
device lifetime. We focused on the comparison of IrO2 and NiO
electrodes with various Ar/O2 gas-flow ratios and utilized the cyclic
voltammetry (CV) method to assess electrochemical properties. It's
observed that Ir02 presented the highest ion diffusion which is good
for the transportation of Li ions. In addition, IrO2 film consists of
a filamentary and interconnected structure, which provides larger
inner pore and contact area to faciliate Li ion transfer in/out
interface of the electrode compared withthe NiO film. This resulted in
Ir02-ECD for a better optical transmit-tance modulation: AT = 50%
higher than that of NiO-ECD AT = 32%, after 1000 cycles. The IrO2-ECD
demonstrated excellent durability after 1000 cycles, which remained at
96% of the original value, and outperformed Ni0-ECD.
In addioion, an IrO, buffer layer was inserted on Ti-doped V2Os (Ti:
V2Os) as a counter electrode using in the same fabrication process.
Experimental results indicated that the buffered ECD demonstrated
excellent optical transmittance modulation up to 57% and good durability
which decayed by only 2% after 1000 cycles.
Key words: Are plasma,
Sputtering, Electrochromic devices, Iridium oxide, Nickel oxide,
Buffer layer, Vanadium pentoxide doping titanium
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