Tailored synthesis of diverse VO2 morphologies for steerable infrared thermochromism

The relentless evolution and enhancement of modern infrared reconnaissance technologies have underscored the necessity for adaptive smart infrared material. Vanadium dioxide (VO 2 ) is a promising candidate due to its metal-insulator transition (MIT), but the fundamental relationship between its nanostructured morphology and its infrared emissivity tuning capability remains unclear. This study aims to establish a clear morphology-performance relationship and uncovering the underlying mechanisms. We proposed a growth mechanism to tune the crystallographic orientation by controlling the precursor solution and hydrothermal process, and successfully synthesized VO 2 nanoparticles with various morphologies (flower-like, spherical-like, rod-like and plate-like). It is found that the room-temperature infrared emissivity (ε) of the plate-like VO 2 exhibited the lowest ε due to the modulation of the dielectric function. Crucially, plate-like VO 2 demonstrated the highest thermochromic infrared emissivity modulation amplitude (Δε = 0.248) during the metal-insulator transition (20–100 °C), which is attributed to a synergistic multi-machine interaction response of the interaction between the carrier concentration and the interfacial effect. These findings deepen the fundamental understanding of the infrared emissivity properties of VO 2 with respect to its morphology and provide a theoretical basis for adaptive infrared stealth.