Strong correlation between optical properties and mechanism in deficiency of normalized self-assembly ZnO nanorods

Abstract

Although, post annealing is an efficient way to annihilate/restructure deficiencies in self-assembly (SA) ZnO nanorods (ZNRs), the detailed investigation about the surface properties of annealed SA-ZNRs is a long standing issue and the major discrepancy is mainly due to single step annealing. We demonstrate the strategic two step annealing process to create reliable structural configuration in SA-ZNRs during the first round of annealing at 800 °C in vacuum (VA process), and create intrinsic defects in the second step of annealing in oxygen rich atmosphere (OA process) to correlate the formation of the defects related to green/orange-red emission. SA-ZNRs annealed in VA-OA processes reveal positive correlations between the oxygen flow rate and formation of oxygen interstitials (Oi) and zinc vacancies (VZn). The OA-VA processes exhibit the relation of residual Oi and additional Vo. According to VA-OA and OA-VA processes, we propose that the green emission in ZnO annealed in oxygen poor/rich condition is mainly due to the formation of Vo/VZn and annealing at oxygen rich condition creates Oi that lead to strong orange-red emission. Rather than O1s, we propose a reliable method by considering the peak shift of Zn2p in XPS to inspect the ZnO matrix, which has good interdependence with the characteristics of PL.

Enhanced Thermoelectric Transport and Stability in Atomic Layer Deposited-HfO2/ZnO and TiO2/ZnO-Sandwiched Multilayer Thin Films

“…The MO II peak represents the O 2ions in the oxygen-deficient regions, which can be related to oxygen vacancies. Finally, the surface adsorbed oxygen such as hydroxyl (OH) and carbonyl (COOH) are characterized by the MO III peak [10,[37][38][39]. Prior to the thermal cycle, ZnO showed the highest MO I among the samples (Fig 4a), which is expected as ZnO bonding requires the least amount of energy to form compared to TiO and HfO [36].…”

Revisiting the Optical Dispersion of Aluminum‐Doped Zinc Oxide: New Perspectives for Plasmonics and Metamaterials

“…[ 1,2 ] Due to its unique features, such as wide direct bandgap at room temperature, large binding energy, high transparency, environment‐friendly properties, and, most importantly, low cost and ease of fabrication, it has continuously been a central component of photovoltaic thin films, optoelectronic devices, and even daily applications such as pharmaceutics and cosmetics. [ 3–6 ] Hence, an investigation about a direct usage of this compound for plasmonic purposes, via manipulating its material characteristics, provides new horizons for future research and applications.…”

ZnO Nano-Flowers Assembled on Carbon Fiber Textile for High-Performance Supercapacitor’s Electrode

“…The reaction kinetics redox potential is satisfied by the reduced oxygen atoms are bonded to Zn. The intensity peak (at 532.5 eV) is caused by the adsorption of loosely bonded oxygen atom "O" on the sample's surface from atmospheric humidity [33]. The XPS, as well as XRD outcomes, confirmed the ZnO nano-flowers formation on a CFT [34].…”