Near-Infrared Light-Responsively Controlled-Release Herbicide Using Biochar as a Photothermal Agent

In this work, near-infrared light (NIRL)-responsively controlled-release herbicide particles (NCHPs) were fabricated using biochar, attapulgite (ATP), NH 4 HCO 3, ethylcellulose (EC), silicon oil (SO), and glyphosate (Gly). Gly and NH 4 HCO 3 were adsorbed onto the ATP nanonetwork that distributed into biochar channels. The resulting complex was granulated and coated by EC and SO to form NCHP. Biochar acted as a photothermal agent, with a photothermal conversion efficiency of 38%, to convert light energy into thermal energy, thus triggering NH 4 HCO 3 decomposition into CO 2 and NH 3 that broke through the coating and facilitated Gly release. Additionally, NCHP showed a higher control efficacy on weeds than Gly alone. Hence, this work provides results for a promising method to control the release of Gly, increase utilization efficiency, and decrease environmental contamination.