Flexible and wearable electronics: Materials, applications and future trends

Flexible and wearable electronics integrate electrical functionality with mechanically compliant substrates that can bend, stretch, twist, or conform to the human body.Unlike conventional rigid electronics, these systems are designed to preserve performance under repeated deformation and during direct contact with complex surfaces.Their development depends on advances in flexible semiconductors, conductive nanomaterials, stretchable interconnects, dielectric materials, encapsulation layers, energy systems, and manufacturing processes.This paper reviews the principal material classes used in flexible and wearable electronics, including organic semiconductors, two-dimensional materials, conductive polymers, metallic nanostructures, carbon-based materials, liquid metals, elastomers, and biodegradable substrates.Applications in healthcare, human-machine interfaces, sports monitoring, soft robotics, electronic skins, energy harvesting, and environmental sensing are examined.The paper also discusses persistent challenges involving durability, biocompatibility, power supply, data security, manufacturing scalability, and environmental sustainability.Future progress is expected to rely on multifunctional materials, self-powered systems, biointegrated devices, recyclable architectures, artificial intelligence, and high-throughput manufacturing.