Intrinsic Control in Defects Density for Improved ZnO Nanorod-Based UV Sensor Performance
Abu Ul Hassan Sarwar Rana1, Shoyebmohamad F Shaikh2, Abdullah M Al-Enizi2
1Intelligent Mechatronics Engineering/Smart Device Engineering, Sejong University, Seoul 05006, Korea.
Nanomaterials (Basel, Switzerland)
|January 17, 2020
Summary
This study reveals that intrinsic crystal defects significantly degrade UV sensor efficiency by trapping light and reducing carrier mobility. Defect-free ZnO nanorods demonstrate superior performance for efficient UV sensing applications.
Area of Science:
- Materials Science
- Nanotechnology
- Sensor Technology
Background:
- Previous UV sensor research focused on surface treatments and Schottky barriers.
- The impact of intrinsic crystal defects on UV sensor efficiency remained unexplored.
Purpose of the Study:
- To investigate the generation of intrinsic crystal defects in ZnO nanorods (ZNRs) and their effect on UV sensor performance.
- To compare the UV sensing characteristics of defect-prone and defect-free ZNRs.
Main Methods:
- Fabrication of hydrothermally grown (S1), Ga-doped (S2), and microwave-assisted grown (S3) ZNRs.
- Characterization of defect states using X-ray diffraction and photoluminescence.
- Evaluation of UV sensor performance based on defect-induced mobility-response model.
Main Results:
- Defect-prone ZNRs (S1, S2) showed compromised UV light absorption and reduced carrier mobility due to defect trapping and scattering.
- Defect-free ZNRs (S3) exhibited superior UV sensor performance.
- S3 demonstrated the highest on/off ratio, fastest response time, longest recombination time, and highest responsivity at 368 nm.
Conclusions:
- Intrinsic crystal defects critically impair UV sensor efficiency by hindering light absorption and carrier mobility.
- Defect-free ZnO nanorods are essential for developing high-performance passive metal oxide-based UV sensors.
- The findings provide insights into optimizing ZNRs for advanced UV sensing applications.
