Low-Temperature Single-Step Inkjet-Printed Metallic Patterns With Self-Regulated Vertical Compositional Gradient

Area of Science:

• Materials Science
• Nanotechnology
• Electrochemistry

Background:

• Printed electronics demand lower processing temperatures and simpler fabrication for medical applications.
• Existing hybrid inks often result in fully-mixed compositional distributions.
• Novel ink formulations are needed for advanced functional patterns.

Purpose of the Study:

• To develop a novel particle-free Ag-Cu hybrid metal-organic decomposition (MOD) ink.
• To achieve single-step, low-temperature fabrication of conductive patterns with controlled composition.
• To demonstrate the feasibility of fabricating a glucose sensor using this novel ink.

Main Methods:

• Formulation of a particle-free Ag-Cu hybrid metal-organic decomposition (MOD) ink.
• Single-step inkjet printing of metallic patterns on rigid and cellulose fiber substrates.
• Sintering under nitrogen (N2) to create vertical compositional gradients and under air for surface functionalization.

Main Results:

• Fabrication of highly conductive (1.88 ± 0.7 × 10^6 S m^-1) metallic patterns at low temperatures (<150 °C).
• In situ formation of Ag and Cu nanoparticles with a self-regulated vertical compositional gradient (Cu on top, Ag beneath) upon sintering under N2.
• Generation of a porous CuO layer with high electrocatalytic activity for glucose sensing upon sintering under air, stable for over 2 hours.

Conclusions:

• The novel Ag-Cu MOD ink enables low-temperature, single-step inkjet printing of functional electronic components.
• The unique vertical compositional gradient enhances conductivity and allows for tailored surface properties.
• This approach demonstrates a viable pathway for fabricating integrated glucose sensors.