Phase Conversion from Hexagonal CuSySe1鈥?i>y to Cubic Cu2鈥?i>xSySe1鈥?i>y: Composition Variation, Morphology Evolution,
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- 作者：Jun Xu ; Xia Yang ; Qingdan Yang ; Wenjun Zhang ; Chun-Sing Lee
- 刊名：ACS Applied Materials & Interfaces
- 出版年：2014
- 出版时间：September 24, 2014
- 年：2014
- 卷：6
- 期：18
- 页码：16352-16359
- 全文大小：476K
- ISSN：1944-8252
文摘
In this work, we report a simple and low-temperature approach for the controllable synthesis of ternary Cu鈥揝鈥揝e alloys featuring tunable crystal structures, compositions, morphologies, and optical properties. Hexagonal CuSySe1鈥?i>y nanoplates and face centered cubic (fcc) Cu2鈥?i>xSySe1鈥?i>y single-crystal-like stacked nanoplate assemblies are synthesized, and their phase conversion mechanism is well investigated. It is found that both copper content and chalcogen composition (S/Se atomic ratio) of the Cu鈥揝鈥揝e alloys are tunable during the phase conversion process. Formation of the unique single-crystal-like stacked nanoplate assemblies is resulted from oriented stacking coupled with the Ostwald ripening effect. Remarkably, optical tuning for continuous red shifts of both the band-gap absorption and the near-infrared localized surface plasmon resonance are achieved. Furthermore, the novel Cu鈥揝鈥揝e alloys are utilized for the first time as highly efficient counter electrodes (CEs) in quantum dot sensitized solar cells (QDSSCs), showing outstanding electrocatalytic activity for polysulfide electrolyte regeneration and yielding a 135% enhancement in power conversion efficiency (PCE) as compared to the noble metal Pt counter electrode.