Hand-printed paper-based devices: Toward green flexible electronics and sensing applications

• Hand-printing on cellulose paper enables low-cost, scalable fabrication of flexible electronics without toxic solvents or sophisticated equipment. • Paper-based devices achieve competitive performance: photodetectors with responsivity up to 52 mA/W, supercapacitors with energy density ~15.1 mWh/cm2, and pressure sensors with sensitivity ~18.42 kPa−1. • Integration of functional nanomaterials (2D chalcogenides, metal oxides, conductive polymers, carbon structures) on paper enhances device functionality for energy harvesting, storage, and sensing. • This approach aligns with green technology and UN Sustainable Development Goals by reducing e-waste and promoting recyclable, biodegradable electronics.