Water-Fertilizer Integrated Eutectogels From Oil in Deep Eutectic Solvent High Internal Phase Emulsions for Soil...

Gels show potential in soil conditioners to restore soil structure and quality for high crop yield. Herein, we propose a synchronous chemical loading system using oil in deep eutectic solvent (O/DES) high internal phase emulsion as template. By removing the internal phase, the interconnected porous network with high surface area (37.5 m² g^-1) is achieved. Benefiting from the porous structure and hygroscopic skeleton, the eutectogel demonstrates attracting hygroscopicity, super absorbency and water-retention behavior, along with reusability even after five cycles. In this strategy, urea, known as a kind of fertilizer, is constructed into the eutectogel network through hydrogen bonds for urea-releasing. Meanwhile, the eutectogel shows additional adhesion and mechanical properties. Compared with blank soil, the eutectogel-soil shows improved moisture harvesting and water holding capabilities. As a benefit of this water-fertilizer integrated system, Brassica rapa demonstrates enhanced germination rate and growth indicators compared with blank soil group in 40-day plant growth experiment. All of the results demonstrate that the eutectogel, as multifunctional eco-product, ensures to address both water and fertilizer retention issues, with high potential of application for sustainable modern agriculture.