Mechanochromic Materials: From Principles, Multi‐Mode Integration, to Emerging Applications

Abstract Mechanochromic materials, which dynamically alter their optical properties in response to mechanical stimuli, represent a versatile platform of smart materials. This review comprehensively overviews recent advances in mechanochromic systems, focusing on two primary mechanisms: structural color modulation and emission color changes. Structural color modulation, often based on reflection, represents the more common approach, while emission color changes, though highly sensitive, constitute a significant complementary strategy. Materials are classified by their different responses to applied strains, including in‐plane (stretch/compression), out‐of‐plane (grinding/shear), and multiaxial (bending) strains. This review also analyzes multi‐stimuli integration with thermochromic, chemochromic, and photochromic functionalities for enhanced versatility. Applications are analyzed, including sensing, displays, anti‐counterfeiting, smart windows, and bioinspired artificial skins, with significant highlights in dual‐signal photonic‐ionic skins and mechanoelectrical sensors. Finally, the opinions are shared on challenges in scalability, environmental stability, spectral tunability, and real‐world implementation, as well as the future directions emphasizing biohybrid systems, artificial intelligence‐driven design, and scalable manufacturing. This review systematically summarizes the progress in mechanochromic materials, which will promote future fundamental research, functionalization, as well as the advancement toward practical applications.