二維結構稀磁性硒化鎘奈米片之合成、鑑定與應用

Abstract

在本論文中，我們摻雜過渡金屬元素（錳、釓、釩及鎳）於二維結構硒化鎘奈米材料中，並探討其合成、結構、光學特性、磁性及產氫應用。利用乙二胺合成出高結晶性之二維奈米片材料，其中雙牙基用來橋接硒化鎘之單層結構，同時在合成步驟中加入具未成對電子之金屬前驅物，能形成奈米級稀磁性半導體。透過穿透式電子顯微鏡、掃描式電子顯微鏡、紫外-可見光光譜儀、螢光光譜儀、X光粉末繞射儀、X光吸收光譜-延伸區精細結構、電子順磁共振光譜儀、超導量子干涉磁量儀等儀器，除鑑定二維稀磁性硒化鎘之形貌、光學性質、晶體結構、化學配位環境、原子位置、磁性等特性，同時比較其光催化分解水效率，來瞭解半導體中摻雜金屬對電荷分離之影響。In this thesis, we doped transition metal elements (manganese, gadolinium, vanadium and nickel) into two-dimensional structures of cadmium selenide nanosheets, to discuss their syntheses, structures, optical properties, magnetic properties and hydrogen evolution application. High crystallinity 2D nanosheet materials were synthesized from ethylenediamine as a bidentate to bridge each monolayer in cadmium selenide. Selected metal ions with unpaired electron precursors were introduced to the synthesis, resulting in dilute magnetic semiconductors in 2D nanoscale. These 2D dilute magnetic cadmium selenides were characterized by transmission electron microscopy, scanning electron microscopy, UV-visible spectroscopy, photoluminescence spectroscopy, X-ray powder diffraction, extended X-ray absorption fine structure, electron paramagnetic resonance spectroscopy and superconducting quantum interference device techniques. In addition to their information in morphology, optical properties, crystal structures, chemical coordination environments, atomic positions, magnetic properties, additional catalytic applications of photocatalytic water splitting were performed to understand the effect of charge separation by doping metal into 2D semiconductors.