Herein, an innovative slow-release fertilizers (SRFs) were developed using a bio-based and waterborne polymeric coating containing starch-g-poly(styrene-co-butylacrylate) latex reinforced with natural char nanoparticles (NCNPs). Several SRF samples were prepared via coating the urea granules with the latex formulations containing different amounts of NCNPs, and their urea release rates were evaluated. The results showed that the presence of NCNPs nano-filler and decreasing the temperature could prolong the urea release time. The performances of the SRF samples were compared to urea granules and a commercial latex coating (SBR, poly(styrene-co-butyl acrylate)) on tomato production in the greenhouse. The results confirmed that NCNPs in coating formulation played an important role in improving plant growth and reducing N-release rate. The efficiencies of all the synthesized SRF samples were higher than the SBR-coated urea confirming the key-role of starch in the coating formulations. In sample containing 1 w% NCNPS (F13), total nitrogen percentage and nitrate content in the aerial parts of tomato plants were increased (21.1%) and decreased (42.1%) compared to the pristine urea, respectively. Particularly, application of F13 formulation could enhance the nitrogen use efficiency (NUE), nitrogen agronomic efficiency (NAE), and nitrogen apparent recovery fraction (NRF), 68.3%, 49.9%, and 29.7%, compared to the urea granules, respectively.

在此，使用含有天然炭纳米颗粒 (NCNP) 增强的淀粉-g-聚(苯乙烯-共-丁基丙烯酸酯) 乳胶的生物基和水性聚合物涂层开发了一种创新的缓释肥料 (SRF)。通过用含有不同量的 NCNP 的乳胶配方包衣尿素颗粒制备了几个 SRF 样品，并评估了它们的尿素释放率。结果表明，NCNPs纳米填料的存在和降低温度可以延长尿素释放时间。将 SRF 样品与尿素颗粒和商业乳胶涂层（SBR，聚（苯乙烯-共-丙烯酸丁酯））在温室番茄生产中的性能进行了比较。结果证实，涂料配方中的NCNPs在促进植物生长和降低氮释放率方面发挥了重要作用。所有合成的 SRF 样品的效率都高于 SBR 涂层尿素，这证实了淀粉在涂层配方中的关键作用。在含有 1 w% NCNPS (F13) 的样品中，与原始尿素相比，番茄植株地上部分的总氮百分比和硝酸盐含量分别增加 (21.1%) 和减少 (42.1%)。特别是，与尿素颗粒相比，F13 配方的应用可以提高氮利用效率 (NUE)、氮农学效率 (NAE) 和氮表观回收率 (NRF)，分别为 68.3%、49.9% 和 29.7%。与原始尿素相比，番茄植株地上部分的总氮百分比和硝酸盐含量分别增加 (21.1%) 和减少 (42.1%)。特别是，与尿素颗粒相比，F13 配方的应用可以提高氮利用效率 (NUE)、氮农学效率 (NAE) 和氮表观回收率 (NRF)，分别为 68.3%、49.9% 和 29.7%。与原始尿素相比，番茄植株地上部分的总氮百分比和硝酸盐含量分别增加 (21.1%) 和减少 (42.1%)。特别是，与尿素颗粒相比，F13 配方的应用可以提高氮利用效率 (NUE)、氮农学效率 (NAE) 和氮表观回收率 (NRF)，分别为 68.3%、49.9% 和 29.7%。