Seo Seon Hee, Jeong Eun Ji, Han Joong Tark, Kang Hyon Chol, Cha Seung I, Lee Dong Yoon, Lee Geon-Woong
†Nano Hybrid Technology Research Center, Korea Electrotechnology Research Institute, Changwon 641-120, Korea.
‡Department of Advanced Materials Engineering, College of Engineering, Chosun University, Gwangju 501-759, Korea.
ACS Appl Mater Interfaces. 2015 May 27;7(20):10863-71. doi: 10.1021/acsami.5b01938. Epub 2015 May 15.
Electrocatalytic materials with a porous structure have been fabricated on glass substrates, via high-temperature fabrication, for application as alternatives to platinum in dye-sensitized solar cells (DSCs). Efficient, nonporous, nanometer-thick electrocatalytic layers based on graphene oxide (GO) nanosheets were prepared on plastic substrates using electrochemical control at low temperatures of ≤100 °C. Single-layer, oxygen-rich GO nanosheets prepared on indium tin oxide (ITO) substrates were electrochemically deoxygenated in acidic medium within a narrow scan range in order to obtain marginally reduced GO at minimum expense of the oxygen groups. The resulting electrochemically reduced GO (E-RGO) had a high density of residual alcohol groups with high electrocatalytic activity toward the positively charged cobalt-complex redox mediators used in DSCs. The ultrathin, alcohol-rich E-RGO layer on ITO-coated poly(ethylene terephthalate) was successfully applied as a lightweight, low-temperature counter electrode with an extremely high optical transmittance of ∼97.7% at 550 nm. A cobalt(II/III)-mediated DSC employing the highly transparent, alcohol-rich E-RGO electrode exhibited a photovoltaic power conversion efficiency of 5.07%. This is superior to that obtained with conventionally reduced GO using hydrazine (3.94%) and even similar to that obtained with platinum (5.10%). This is the first report of a highly transparent planar electrocatalytic layer based on carbonaceous materials fabricated on ITO plastics for application in DSCs.
通过高温制备工艺，已在玻璃基板上制造出具有多孔结构的电催化材料，用作染料敏化太阳能电池（DSC）中铂的替代品。基于氧化石墨烯（GO）纳米片的高效、无孔、纳米厚的电催化层是在塑料基板上于≤100°C的低温下通过电化学控制制备的。在氧化铟锡（ITO）基板上制备的单层富氧GO纳米片在酸性介质中于狭窄扫描范围内进行电化学脱氧，以便以最少的氧基团消耗获得轻度还原的GO。所得的电化学还原GO（E-RGO）具有高密度的残留醇基，对DSC中使用的带正电荷的钴络合物氧化还原介质具有高电催化活性。在涂有ITO的聚对苯二甲酸乙二酯上的超薄、富含醇的E-RGO层成功用作轻质低温对电极，在550nm处具有约97.7%的极高透光率。采用高度透明、富含醇的E-RGO电极的钴（II/III）介导的DSC表现出5.07%的光伏功率转换效率。这优于使用肼常规还原GO所获得的效率（3.94%），甚至与使用铂所获得的效率（5.10%）相似。这是关于在ITO塑料上制造用于DSC的基于碳质材料的高度透明平面电催化层的首次报道。
