Browsing by Author "Yang, Shun-Shing"

Now showing 1 - 4 of 4

Metal Nanoparticle-Decorated Two-Dimensional Molybdenum Sulfide for Plasmonic-Enhanced Polymer Photovoltaic Devices
(2015-08-01)
Chuang, Ming-Kai
;
Yang, Shun-Shing
;
Chen, Fang-Chung
;
光電工程學系
;
Department of Photonics
Atomically thin two-dimensional (2D) transition metal dichalcogenides have also attracted immense interest because they exhibit appealing electronic, optical and mechanical properties. In this work, we prepared gold nanoparticle-decorated molybdenum sulfide (AuNP@MoS2) through a simple spontaneous redox reaction. Transmission electron microscopy, UV-Vis spectroscopy, and Raman spectroscopy were used to characterize the properties of the AuNP@MoS2 nanomaterials. Then we employed such nanocomposites as the cathode buffer layers of organic photovoltaic devices (OPVs) to trigger surface plasmonic resonance, leading to noticeable enhancements in overall device efficiencies. We attribute the primary origin of the improvement in device performance to local field enhancement induced by the effects of localized surface plasmonic resonance. Our results suggest that the metal nanoparticle-decorated two-dimensional materials appear to have great potential for use in high-performance OPVs.
Plasmonic Effects on Bulk Heterojunction Polymer Solar Cells: A Transient Photovoltage and Differential Charging Study
(2017-08-01)
Kok, Soon Yie
;
Hsieh, Zong-Chun
;
Chou, Chun-Hsien
;
Yang, Shun-Shing
;
Chuang, Ming-Kai
Transient photovoltage and differential charging experiments have been carried out to investigate the plasmonic effects in organic photovoltaic devices (OPVs). We observed that the carrier lifetimes became longer after the Au nanoparticles were blended into the OPVs. Additionally, the charge carrier densities also became higher in the bulk of the device. The carrier lifetime, however, usually follows an inverse power relationship with the increasing charge density in OPVs fabricated base on the concept of bulk heterojunctions. Therefore, we conclude that one of the limitations for the plasmonic approaches could be the strong bimolecular recombination.
Plasmonic-Enhanced Organic Photovoltaic Devices for Low-Power Light Applications
(2018-05-01)
Teng, Nai-Wei
;
Yang, Shun-Shing
;
Chen, Fang-Chung
;
光電工程學系
;
Department of Photonics
In this study, we prepared plasmonic-enhanced organic photovoltaic (OPV) devices incorporating gold nanoparticles (Au NPs) for low-power lighting applications. Gold NP-decorated graphene oxides were incorporated into the hole-transporting and active layer layers of the OPVs to trigger plasmonic effects. After adding the Au NPs, the devices exhibited higher photocurrents and power conversion efficiencies (PCEs) under both 1-sun and low-level illumination conditions; PCE enhancement factors of greater than 20% were achieved. Most interestingly, the device enhancement factors were much higher under low-level lighting than they were under sunlight. We attribute the improvement in device efficiency to the localized surface plasmon resonance originating from the Au NPs.
Toward High-Performance Polymer Photovoltaic Devices for Low-Power Indoor Applications
(2017-12-01)
Yang, Shun-Shing
;
Hsieh, Zong-Chun
;
Keshtov, Muchamed L.
;
Sharma, Ganesh D.
;
Chen, Fang-Chung
This article describes the performance of organic photovoltaic (OPV) devices, incorporating three different polymer/fullerene derivative blends, under low-level lighting conditions. The devices exhibit much higher power conversion efficiencies (PCEs) under indoor lighting conditions than they do under sunlight. The best-performing device is capable of delivering a power output of 22.57Wcm(-2), corresponding to a PCE of 13.76%, under illumination with indoor lighting conditions at 500 lux. Increasing the open-circuit voltage (V-oc) of the OPV devices is the most critical factor for achieving high device performance for low-power indoor applications. Therefore, the device power output will be maximized if we could obtain a larger energy difference between the highest occupied molecular orbital of the polymer donor and the lowest unoccupied molecular orbital of the electron acceptor, thereby ensuring a high value of V-oc.