Browsing by Author "Wu, Wen-Ti"

Now showing 1 - 2 of 2

Compact TiO2 films with sandwiched Ag nanoparticles as electron-collecting layer in planar type perovskite solar cells: improvement in efficiency and stability
(2018-01-01)
Abate, Seid Yimer
;
Wu, Wen-Ti
;
Pola, Someshwar
;
Tao, Yu-Tai
;
應用化學系
Fabrication of perovskite solar cells (PSCs) in a simple way with high efficiency and stability remains a challenge. In this study, silver nanoparticles (Ag NPs) were sandwiched between two compact TiO2 layers through a facile process of spin-coating an ethanolic AgNO3 solution, followed by thermal annealing. The presence of Ag NPs in the electron-transporting layer of TiO2 improved the light input to the device, the morphology of the perovskite film prepared on top, and eliminated leakage current. Photoluminescence and electron mobility studies revealed that the incorporation of Ag NPs in the ETL of the planar PSC device facilitated the electron-hole separation and promoted charge extraction and transport from perovskite to ETL. Hysteresis-free devices with incorporated Ag NPs gave a high average short-circuit current density (J(sc)) of 22.91 +/- 0.39 mA cm(-2) and maximum power conversion efficiency of 17.25%. The devices also showed enhanced stability versus a control device without embedded Ag NPs. The possible reasons for the improvement are analyzed and discussed.
Performance Characterization of Dye-Sensitized Photovoltaics under Indoor Lighting
(2017-04-20)
Chen, Chia-Yuan
;
Jian, Zih-Hong
;
Huang, Shih-Han
;
Lee, Kun-Mu
;
Kao, Ming-Hsuan
Indoor utilization of emerging photovoltaics is promising; however, efficiency characterization under room lighting is challenging. We report the first round-robin interlaboratory study of performance measurement for dye-sensitized photovoltaics (cells and mini-modules) and one silicon solar cell under a fluorescent dim light. Among 15 research groups, the relative deviation in power conversion efficiency (PCE) of the samples reaches an unprecedented 152%. On the basis of the comprehensive results, the gap between photometry and radiometry measurements and the response of devices to the dim illumination are identified as critical obstacles to the correct PCE. Therefore, we use an illuminometer as a prime standard with a spectroradiometer to quantify the intensity of indoor lighting and adopt the reverse-biased current voltage (I-V) characteristics as an indicator to qualify the I-V sampling time for dye-sensitized photovoltaics. The recommendations can brighten the prospects of emerging photovoltaics for indoor applications.