Stimuli-responsive wood-based products: A systematic literature review on typologies, research drivers and gaps

Wood-based stimuli-responsive products, also referred to as “smart wood”, are innovative systems capable of dynamic interaction with their surroundings. Wood may act either as an active component or as a structural support. The responsive behaviour can be intrinsic to wood, enhanced through specific modifications, or conferred via combination with other materials. Interest in these products has grown remarkably in recent years, resulting in a rapidly expanding research field. In this review, a systematic approach was adopted to examine the current state of the art of smart wood products in literature (Q1), identify research drivers (Q2), and highlight gaps and perspectives (Q3). A total of 25379 scientific contributions published in English in the last decade was collected from the Scopus and Web of Science databases. The analysis of the 413 selected studies revealed a wide range of smart wood products with diverse responsiveness. Reported response mechanisms include hygro-, photo-, and pH-responsiveness, with applications across architecture, food sector, healthcare, and soft robotics (Q1). Research is primarily driven by wood’s sustainability and its porous microstructure, which facilitates functionalisation and integration with active compounds (Q2). Investigated prototypes mostly remain at low Technological Readiness Level due to limitations in upscaling, performance competitiveness, and long-term use (Q3). Overall, this review provides a comprehensive and cross-sectoral overview of smart wood-based products, intended as a reference framework to support their development and use in various application sectors.