Solvothermal synthesis of TiO₂nanospheres for non-volatile memory and synaptic learning applications

Area of Science:

• Materials Science
• Nanotechnology
• Solid-State Electronics

Background:

• Titanium dioxide (TiO₂) is a versatile material with potential in advanced electronic applications.
• Developing efficient synthesis methods for nanostructured TiO₂ is crucial for enhancing device performance.
• Non-volatile memory and neuromorphic computing require materials with stable resistive switching properties.

Purpose of the Study:

• To synthesize TiO₂ nanospheres (NSs) via a one-pot solvothermal method.
• To investigate the structural, optical, morphological, and compositional properties of TiO₂ NSs.
• To evaluate the performance of TiO₂ NSs in non-volatile memory and neuromorphic computing applications.

Main Methods:

• One-pot solvothermal synthesis of TiO₂ nanospheres.
• Characterization using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS).
• Fabrication and testing of Ag/TiO₂ NSs/FTO devices for resistive switching (RS) and synaptic behavior.

Main Results:

• Rietveld refinement confirmed the tetragonal anatase structure of TiO₂.
• FESEM and TEM images verified the nanosphere morphology.
• The fabricated devices exhibited bipolar RS behavior with good endurance (5000 cycles) and retention (5000 s).
• Ohmic and space charge-limited current mechanisms governed charge transport.
• The devices successfully mimicked synaptic functions like potentiation-depression and paired-pulse facilitation.

Conclusions:

• The solvothermal method effectively produced TiO₂ NSs suitable for electronic applications.
• Optimized TiO₂ NS-based devices show promising characteristics for non-volatile memory and neuromorphic computing.
• The demonstrated synaptic mimicry highlights the potential of TiO₂ NSs in brain-inspired computing.