Fully Written Flexible Potentiometric Sensor Using Two-Dimensional Nanomaterial-Based Conductive Ink.

Area of Science:

• Materials Science
• Electrochemistry
• Sensor Technology

Background:

• Growing demand for flexible, portable, and cost-effective electronics.
• Need for novel fabrication techniques for electronic components and devices.

Purpose of the Study:

• To develop an all-written potentiometric sensor inspired by handwriting.
• To create a reliable and stable sensor for cadmium ion detection.

Main Methods:

• Utilized a Chinese brush pen-based writing technique.
• Formulated a writing ink with graphene nanosheets (GN), Triton X-100, and xanthan gum.
• Constructed an all-solid-state potentiometric sensor by writing a cadmium ion selective membrane (Cd²⁺-ISM) and reference membrane (RM) on a graphene nanosheet-based writing electrode (GN-WE).

Main Results:

• The GN-WE exhibited excellent conductivity, fast electron-transfer kinetics, stability, and flexibility.
• The developed sensor achieved a large bulk capacitance (41.67 μF) and superior potential stability (0.156 mV h⁻¹ drift).
• Performance surpassed traditional sensors using glassy carbon electrodes (GCE).

Conclusions:

• The all-written potentiometric sensor demonstrates significant advantages over conventional methods.
• This novel sensor is a reliable and stable platform for detecting cadmium ions in environmental and food samples.
• The handwriting-inspired fabrication technique offers a promising approach for low-cost, flexible electronics.