Interfacial engineering of conformal titanium oxide nanofilms on porous carbon supercapacitor electrodes via atomic layer deposition

The growth mechanism of titanium dioxide onto activated carbon was determined through the growth per cycle values. The crystal structure of the deposited films was determined using x-ray diffraction and the surface defect sites of the samples are measured by Raman spectroscopy. X-ray photoelectron spectroscopy was utilized to confirm the presence of titanium dioxide and it associated surface functional groups. Surface morphology and elemental composition studies were utilized to analyze the film uniformity and a high resolution cross-sectional images to study the film conformity. Extensive charge-discharge cycles were performed to calculate the specific capacitance and the equivalent series resistance. Cyclic voltammetry studies were utilized to study the electrochemical behavior of the bare and titanium dioxide coated activated carbon electrodes.

本研究通过每循环生长量，明确了二氧化钛在活性炭表面的生长机制。采用X射线衍射（x-ray diffraction）表征沉积薄膜的晶体结构，通过拉曼光谱法（Raman spectroscopy）测定样品的表面缺陷位点。利用X射线光电子能谱（X-ray photoelectron spectroscopy）验证二氧化钛的存在及其相关表面官能团。通过表面形貌与元素组成分析，考察薄膜的均匀性，并借助高分辨率截面图像研究薄膜的保形性。开展了大量充放电循环测试以计算比电容与等效串联电阻。采用循环伏安法（cyclic voltammetry）探究裸活性炭电极与二氧化钛包覆活性炭电极的电化学行为。