Conventional physical unclonable functions (PUFs), although delivering unique and non-replicatable identifiers for hardware security authentication and key component anti-counterfeiting applications, struggle to provide long-term reliable support under extreme environments such as nuclear reactors, fusion devices, and space radiation, which feature intense radiation and high temperatures. Here, we report a highly robust PUF architecture derived from the intrinsic crystallographic disorder of polycrystalline diamond microtextures. By analyzing electron backscatter diffraction (EBSD) patterns, a multidimensional security framework is established that integrates three complementary encoding dimensions: multi-base numerical conversion of individual microtexture features for primary key generation; three-dimensional topological reconstruction through fusion of single- and multi-directional EBSD maps; and crystallographic coding based on the statistical distribution of (100), (110), and (111) lattice planes. Together, these elements form a three complementary encoding dimensions with exceptionally high entropy and unclonability. To enable deployment across heterogeneous application scenarios, both rigid polycrystalline diamond substrates and self-supported flexible diamond films are developed. The rigid architecture provides ultrahard chemically inert planar security for chip-level authentication, while the flexible diamond films combine curvature adaptability with extreme durability, enabling secure labeling of complex and deformable surfaces such as medical devices. Sharing a unified microtexture-based encoding mechanism, their complementary platforms establish a versatile security solution that seamlessly integrates rigidity and flexibility for high-value electronic components and advanced anti-counterfeiting applications.

Deep-red afterglow materials with high emission efficiency remain fundamentally limited by inefficient intersystem crossing (ISC) and significant nonradiative decay of triplet excitons under solid-state conditions. Herein, we establish a space-confined triplet-singlet energy transfer (ET) design to achieve efficient long-wavelength afterglow emission in metal-free carbon dot hybrids. Urea-induced heteroatom engineering introduces (n, π*) states that facilitate ISC and increase triplet population, while an (3-aminopropyl) triethoxysilane-derived siloxane network rigidifies the microenvironment and suppresses vibrational relaxation, thereby stabilizing triplet excitons. Meanwhile, surface-state modulation enables favorable triplet energy alignment between the carbon core and surface-associated emissive centers, facilitating efficient triplet-mediated ET. This cooperative regulation results in bright deep-red afterglow centered at 662 nm with a photoluminescence quantum yield of 45.2%. Comparative investigations with red-emissive counterparts reveal that surface-state modulation and molecular rigidification play complementary roles in wavelength tunability and emission efficiency. The resulting materials demonstrate potential in time-resolved optical encryption and persistent afterglow lighting. This work provides mechanistic insight into triplet regulation in confined carbon systems and suggests a viable strategy for improving long-wavelength metal-free afterglow performance.