Retention, a crucial process in pesticide application, is heavily affected by the extremely low surface energy and micro/nanostructure of plant leaves. The inadequate retention like bouncing, splashing, and drifting often give rise to severe soil and groundwater pollution. In this article, we present an unprecedented topology-regulation approach that significantly contributes to this issue. A series of pesticide-loaded “hat”-shaped Janus carriers (HJCs) are synthesized via emulsion interfacial polymerization and characterized by scanning electron microscope, thermogravimetric analyzer, energy-dispersive spectrometer, and Fourier transform infrared spectroscopy. Upon spraying on plant leaves, the pesticide-loaded HJCs can embed with the micropapillae and nanosplinters on leaves driven by the “hanger-hat” topology effect, consequently leading to the enhanced retention evaluated by the deposition and flush resistance experiments. Moreover, the release behavior of pesticide-loaded HJCs is found to match the Ritger-Peppas model and finally achieves sustained release. Additionally, the generality of the HJCs synthetic strategy is also studied and applicable to multiple pesticides. This study not only provides a new strategy for increasing pesticide retention on plant leaves but also opens a promising aspect for the applications of Janus carriers in agriculture.

The addition of a surfactant is a constructive strategy to enhance the deposition of pesticides on plant leaves in agriculture. However, currently used surfactants normally require to be used at high concentrations, and most of them are anionic or nonionic. In this work, we found that didecyldimethylammonium bromide (DDAB), a double-chain cationic surfactant, can not only inhibit droplets from receding and rebounding but also promote sufficient spreading on paraffin and Chenopodium album L. leaf surfaces at an ultralow concentration (0.05%), in comparison with widely reported sodium dodecyl sulfate (SDS) and bis(2ethylhexyl)sulfosuccinate (AOT). This phenomenon is attributed to the fast adsorption kinetics of DDAB from the bulk to the newly created interface (mere 100 ms), decreasing the surface tension significantly. Field experiments further prove that the addition of DDAB can significantly improve the control efficiency of herbicides. Our findings provide a simple and effective way for improving the droplet deposition on hydrophobic plant surfaces, which may lead to economic and environmental benefits in the future.

Despite small-molecule surfactants and polymers being widely used as pesticide adjuvants to inhibit droplet bouncing and splashing, they still have intrinsic drawbacks either in the easy wind drift and evaporation, the unfavorable wettability, or the usage of nonrenewable resources. In this paper, we found that upon droplet impacting, 1D nanofibers assembled from natural glycyrrhizic acid (GL) could pin on the rough hydrophobic surface and delay the retraction rate of droplets effectively. Using GL as a tank-mixed adjuvant, the efficiency of glyphosate to control the weed growth was improved significantly in the field experiment, which addressed the dilemmas of current adjuvants elegantly. Our work not only provides a constructive way to overcome droplet bouncing but also prompted us to verify in future if all 1D nanofibers assembled from different small molecules can display similar control efficiencies.

A Ni2P/g-C3N4 hybrid photocatalyst were in situ fabricated via a one-step co-heating solution approach. The integrated photocatalyst demonstrated extraordinary H2 evolution and excellent durability due to the unique Ni(δ+)–N(δ−) chemical bonding.

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