Biopolymer-Gated Graphene Transistors: An Eco-Friendly Approach to Two-Dimensional Electronics

The rapid increase in electronic waste (e-waste) has demanded the development of sustainable and eco-friendly materials for use in electronics manufacturing. This study investigates three biodegradable biopolymers─chitosan, sodium alginate, and xanthan gum─as gate dielectric materials for graphene-based transistors, representing a significant step toward reducing the environmental impact of e-waste. An evaluation of these biopolymers for transparency, thermal stability, and mechanical properties was performed. To understand the capacitive behavior, capacitance-voltage profiling and electrochemical impedance spectroscopy methods were employed. The application of these methods enabled the distinction between quantum capacitance and electric double-layer capacitance, which enhanced the understanding of the interface between graphene and the biopolymer-based gate dielectric materials. Through this procedure, accurate values of carrier mobility and carrier density, which are crucial for transistor performance assessment, are determined. The results demonstrate the potential benefits of biodegradable biopolymers in advancing environmentally friendly electronics and reducing e-waste.