Biochar has been extensively studied as a promising carrier material for fertilizers and an ideal adsorbent for the removal of pesticides. Yet, the application of biochar for simultaneously eliminating the pollution from the agricultural use of fertilizers and pesticides remains unexplored. Herein, we develop P-loaded biochar-based fertilizers (PBC) by the co-pyrolysis of cotton straw and H₃PO₄. The slow-release performance of PBC and their adsorption properties toward pesticides are investigated. The results indicate that the PBC leads to the improvement of adsorption performance, with the maximum adsorption capacities of lambda-cyhalothrin (LAC) for PBC and pristine biochar are 55.90 mg/g and 42.71 mg/g, respectively. Additionally, the adsorption of LAC is beneficial for the improvement of slow-release performance of PBC. The release ratios of P from PBC within 30 days reach 100.0% and 83.5% in water and LAC solution, respectively, demonstrating the existence of synergistic effects between the adsorption of pesticides and the slow release of nutrients. The mechanistic investigation reveals that the pretreatment of H₃PO₄ facilitates to activate more surface functional groups of PBC, contributing greatly to the improved adsorption of LAC. The adsorption of LAC reduces the BET of PBC with pore filling, enabling slower release rate of nutrients from PBC.

生物炭已被广泛研究为有前途的肥料载体材料和理想的农药去除剂。然而，生物炭用于同时消除肥料和杀虫剂的农业使​​用中的污染的应用仍未被探索。在这里，我们通过棉秸秆与H ₃ PO ₄的共热解开发了含磷生物炭基肥料（PBC）。。研究了PBC的缓释性能及其对农药的吸附性能。结果表明，PBC导致吸附性能的提高，λ-氟氯氰菊酯（LAC）对PBC和原始生物炭的最大吸附容量分别为55.90 mg / g和42.71 mg / g。另外，LAC的吸附有利于改善PBC的缓释性能。在水和LAC溶液中，PBC在30天之内的P释放率分别达到100.0％和83.5％，证明了农药吸附与养分缓慢释放之间存在协同作用。机理研究表明，H ₃ PO ₄的预处理有助于活化PBC的更多表面官能团，极大地改善了LAC的吸附。LAC的吸附会通过孔隙填充降低PBC的BET，从而使营养物质从PBC释放的速度变慢。