Type II ZnO-MoS₂ Heterostructure-Based Self-Powered UV-MIR Ultra-Broadband p-n Photodetectors

Area of Science:

• Optoelectronics
• Materials Science
• Nanotechnology

Background:

• Photodetectors are crucial for various sensing applications.
• Achieving ultra-broadband detection (UV to MIR) remains a challenge.
• ZnO-MoS2 heterostructures offer potential for enhanced optoelectronic properties.

Purpose of the Study:

• To fabricate and characterize ZnO-MoS2 heterostructure-based photodetectors.
• To investigate their performance across an ultra-broad spectral range (365 nm-10 μm).
• To explore potential applications in optical memory, neuromorphic computing, and sensing.

Main Methods:

• Fabrication using RF magnetron sputtering, spin coating, and annealing.
• Structural and optical characterization (e.g., light absorption, charge separation).
• Electrical measurements (I-V characteristics) and response time analysis.
• Density Functional Theory (DFT) simulations for band alignment and bandgap analysis.

Main Results:

• Successful fabrication of ZnO-MoS2 p-n heterojunctions.
• Ultra-broadband spectral response from UV to MIR.
• Observed light-controlled hysteresis for potential memory applications.
• Self-powered operation with fast response/recovery times (~100 ms).
• DFT confirmed Type II band alignment and tunable bandgap (0.20 eV with Mo vacancies).

Conclusions:

• ZnO-MoS2 heterostructures demonstrate high-performance, ultra-broadband photodetection.
• Defect engineering (Mo vacancies) enables tunable bandgap for extended detection.
• The developed photodetectors are suitable for imaging, environmental monitoring, and IoT sensing.
• This work presents a cost-effective strategy for advanced optoelectronic devices.