Inorganic Photonic Microspheres with Localized Concentric Ordering for Deep Pattern Encoding and Triple Sensory Microsensor

Abstract Photonic microspheres offer building units with unique topological structures and specific optical functions for diverse applications. Here, a new class of inorganic photonic microspheres with superior robustness, optical and electrical properties is reported by introducing a unique localized concentric ordering architecture and chemical interaction, which further serve as building blocks for deep pattern encoding and multiple sensory optoelectronic devices. Benefiting from localized concentric ordering architecture, the resultant photonic microspheres demonstrate orientation‐ and angle‐independent structural colors. Notably, the formation of well‐combined lamellae inorganic layers by chemical interaction grants the microspheres superior mechanical robustness, excellent solvent resistance, thermal stability, and multiple optoelectronic properties simultaneously, rarely seen in previous reports. Owing to these merits, such microspheres are used to construct diverse encoded photonic patterns for anti‐counterfeiting applications. Interestingly, cross‐communication among neighboring microspheres creates complex photonic sub‐patterns, which provide “fingerprint information” with deep encryption security. Moreover, a single photonic microsphere‐based optoelectronic microsensor is demonstrated for the first time, which achieves appealing application for real‐time health monitoring and safety warning toward triple environmental stimuli. This work not only provides a new kind of robust, multifunctional photonic material, but also opens a new avenue for their uses as complexed pattern encoding and multi‐parametric sensing platforms.