Conductive biocarbon from agricultural waste for sustainable and smart agriculture

Agricultural waste-derived biocarbons are emerging as sustainable, low-cost alternatives to conventional nanocarbons for smart agriculture. Agricultural residues can be thermochemically converted into conductive biocarbons whose graphitization degree, hierarchical porosity, and surface chemistry are tunable through control of pyrolysis conditions and activation strategy. This review first examines the synthesis and structural design of agricultural waste-derived conductive biocarbons, highlighting structure-property relationships that link carbonization temperature and activation method to electrical conductivity and percolation behavior. It then examines their use in smart agriculture, encompassing flexible platforms for real-time plant physiological monitoring, electrochemical sensors for food analysis, and moisture and temperature sensors in smart farming systems. Key challenges are identified, and future prospects are outlined for biocarbon sensors. By bridging agricultural waste valorization with the demands of precision and smart farming, agricultural waste-derived conductive biocarbons provide a versatile material platform for more resilient, data-rich, and environmentally compatible agricultural systems.