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Evaporation patterns of liquid droplets containing nanoparticles or colloids have extensive applications in diagnostics and printing. Controlling these patterns by studying the evaporation behavior of colloidal droplets on surfaces is important for enhancing sensing platforms. In this study, A liquid‐repellent microcavity surface is introduced to robustly capture deposited analytic particles. The proposed microcavity surface maintains stable air pockets for liquid repellency and strong pinning for the spatial stabilization of the evaporating droplet, thereby resulting in a coffee‐ring concentration. This microcavity surface also acts as a "microcontainer" for the deposited particles, thereby protecting them against external damage. To demonstrate the multifaceted capabilities of microcavity surfaces, further comparison is done of three different surface structures, planar, micropillared, and that with microcavities in a hexagonal arrangement, by analyzing their evaporation dynamics and dried deposit patterns. The microcavity surface exhibits superior particle capture, thereby revealing its applicability in on‐site testing. Using the direct rapid sampling of analytical materials, the potential of the fabricated microcavity surface for point‐of‐care testing is demonstrated. The proposed microcavity surfaces suggest new avenues for the development of more robust and sensitive sensing platforms. [ABSTRACT FROM AUTHOR]

Owing to their unique structural robustness, interconnected reentrant structures offer multifunctionality for various applications. a scalable multistep roll-to-roll printing method is proposed for fabricating reentrant microcavity surfaces, coined as wetting-induced interconnected reentrant geometry (WING) process. The key to the proposed WING process is a highly reproducible reentrant structure formation controlled by the capillary action during contact between prefabricated microcavity structure and spray-coated ultraviolet-curable resins. It demonstrates the superior liquid repellency of the WING structures, which maintain large contact angles even with low-surface-tension liquids, and their robust capability to retain solid particles and liquids under external forces. In addition, the scalable and continuous fabrication approach addresses the limitations of existing methods, providing a cost-effective and high-throughput solution for creating multifunctional reentrant surfaces for anti-icing, biofouling prevention, and particle capture., (© 2024 The Author(s). Advanced Materials published by Wiley‐VCH GmbH.)