Compressive Strain of La Induced in ZnO Nanorods by Interstitial Site Passivation for Enhanced Charge Carrier Transport Mechanism
来源：ACS Publications
Zinc oxide (ZnO) nanorods (NRs) doped with lanthanum (La) were synthesized via a low-temperature 90 °C hydrothermal method to investigate defect passivation and charge transport enhancement. Structural and spectroscopic characterization reveals that La3+ preferentially adsorbs at ZnO surfaces and grain boundaries, inducing compressive strain that suppresses defect formation without lattice substitution. Morphological studies demonstrate improved surface uniformity in La-doped NRs, while Raman spectroscopy shows reduced defect-related modes at 1 mol % La doping. XPS analysis confirms interfacial La3+ localization through characteristic 3.5 eV satellite features and minimal binding energy shifts of merely 0.2 eV. The optimal 1 mol % La-doped ZnO exhibits a conductivity of 5.46 S/m at 3.25 eV bandgap with a 4.6% improvement over high-temperature (>300 °C) synthesized La-ZnO references. While pristine ZnO shows higher absolute conductivity, these results demonstrate that low-temperature hydrothermal processing can achieve comparable electronic property enhancement to conventional high-temperature methods. This work provides fundamental insights into interfacial doping strategies for ZnO-based materials, with potential implications for optoelectronic applications.
In this study, we propose a novel method for the synthesis and characterization of La-doped zinc oxide nanostructures as ETLs in PSCs. This approach, which utilizes a low-temperature hydrothermal synthesis technique, represents a previously unexplored strategy technique. This low-temperature approach paves the way for the development of flexible PSCs, which are limited in heat exposure to the substrate. Herein, we systematically investigate the influence of the La-doping concentration on the properties of ZnO nanostructures, focusing on their structural, optical, and electrical characteristics. This study aims to provide fundamental insights into the material’s potential as an ETL in PSCs, addressing a significant gap in the current understanding of La-doped ZnO. By exploring these properties, we contribute to the broader development of advanced electronic and optoelectronic materials, supporting future innovations in photovoltaic and energy-related applications.