Facet‐Dependent On‐Surface Reactions in the Growth of CdSe Nanoplatelets. (21st October 2019)

• Record Type: Journal Article
• Authors: Zhu, Chenqi; Chen, Dongdong; Cao, Weicheng; Lai, Runchen; Pu, Chaodan; Li, Jiongzhao; Kong, Xueqian; Peng, Xiaogang
• Is Part Of: Angewandte Chemie. Volume 131:Number 49(2019)
• Page Start: 17928
• Page End: 17934
• Publication Date: 2019-10-21
• Subjects: Cadmiumselenid -- Nanokristalle -- Oberflächenreaktionen -- Reaktionskinetik; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201909576
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Facet‐dependent on‐surface reactions are systematically studied on zinc‐blende CdSe nanoplatelets with atomically‐flat {001} basal facets and small yet non‐polar side facets. The on‐surface half‐reactions between the surface Se sites and Cd carboxylates in the solution are qualitatively equivalent to those on the spheroidal counterparts. Conversely, the on‐surface half‐reactions between the surface Cd sites and the activated Se precursors in solution show a strong facet‐dependence, which includes three distinguishable stages. In the first stage, the Se precursors adsorb onto the small and non‐polar side facets of the nanoplatelets. The second stage is initiated by the adsorbed Se precursors at the side‐basal plane edges and proceeds from the edges to the center of the basal planes in quasi‐zeroth‐order kinetics. In the third stage, the nanoplatelets are dismantled, which includes the creation of a hole in the middle and a build‐up of thick edges. Abstract : Wachstumsphasen eines Plättchens : Die Oberflächenreaktionen auf Nanoplättchen zwischen Cd‐Zentren auf der Oberfläche und aktivierten Se‐Vorläufern in Lösung sind stark von der Kristallfläche abhängig. Der Prozess verläuft in zwei Stufen – schnelle Adsorption auf nicht‐polaren Seitenflächen und langsame Oberflächenreaktion auf den polaren {100}‐Basalflächen – sowie einer destruktiven Stufe.