Recent advances in cellulose-based paper for flexible pressure sensors: A review

As key components in human-machine interaction and health monitoring, flexible pressure sensors are facing growing demands for environmental sustainability. Conventional polymer-based sensors predominantly rely on non-degradable, petroleum-derived materials, exacerbating the problem of electronic waste pollution. In contrast, paper-based flexible pressure sensors, benefiting from the renewability, biodegradability, and low cost of cellulose, demonstrate strong potential as green substrates for electronic devices. This review systematically summarizes recent advances in cellulose paper-based flexible pressure sensors. The main content includes introducing the signal transduction mechanisms of different types of cellulose paper-based pressure sensors, discussing key technologies for preparing highly conductive cellulose paper materials via pen writing, printing, coating, and chemical modification; elucidating structural optimization strategies including multilayer stacking, microstructured texturing, and origami/kirigami-inspired topological designs as pathways to enhance device performance such as sensitivity and detection range; demonstrating the application effectiveness of hydrophobic encapsulation, flame-retardant treatment, and mechanical reinforcement in improving the durability of cellulose paper-based sensors under humid, high-temperature, and extreme mechanical conditions. Finally, the unresolved issues and main challenges that currently restrict the practical application of cellulose paper-based flexible pressure sensors were discussed.