Sustainable, One-Pot Synthesis of Porous Hollow Silica Microcapsules via Choline-Based Ionic Liquid for Improved Locust Management

Porous hollow silica microcapsules enable stable, sustainable pesticide formulations, but their synthesis is complex and solvent-dependent. In this study, a green method was developed using a choline-based ionic liquid as both a solvent and soft template. The resulting choline-chlorantraniliprole-porous hollow silica (CHO–CHL–PHS) microcapsules achieved a chlorantraniliprole loading of 47.17%, exhibited a spherical morphology, and were synthesized without organic solvents or additional surfactants. The microcapsules improved the photostability of chlorantraniliprole, extending its UV half-life from 0.89 to 1.27 h, and showed sustained diffusion release at pH 5.0–10.0. Laboratory bioassays demonstrated that CHO–CHL–PHS possessed significantly higher virulence against Locusta migratoria manilensis nymphs than technical-grade CHL. Persistence trials confirmed that its efficacy within 7 days was superior to that of a commercial suspension concentrate. Safety assessments showed no phytotoxicity on ryegrass or corn and reduced toxicity to zebrafish. This study offers a promising strategy for developing effective and environmentally compatible agrochemical formulations.