Numerical optimization of the physical properties of thermochromic layers based on spin transition materials for cold coating applications

This article explores the theoretical potentialities for using spin-crossover (SCO) materials to insulate buildings against photothermal effects. While many works on their possible applications as memories, actuators, displays, sensors, etc. are often reported in literature, the present theme is absent from the study of the properties of SCO materials. Our strategy is based on the use of the thermally-induced first-order transition of SCO solids, which is accompanied by thermochromic properties, to pave the way for their use as a protective layer improving the energy efficiency of buildings, notably by protecting them from photothermal effects caused by the sun’s heat. In this context, we propose detailed numerical simulations and parametric analysis of physical properties of the SCO layer (thickness, heat diffusion, ligand field, …), which are key factors regulating their thermal performances. This work provides predictive guidelines for engineering applications and opens up new avenues for experimental investigations of SCO-based thermal protection systems.