Defect Management and Multi‐Mode Optoelectronic Manipulations via Photo‐Thermochromism in Smart Windows.

Smart windows with adjustable transmittance via physical stimuli are eagerly desired for sorts of energy‐saving lighting systems. However, reciprocal trade‐off relationship such as high transparency and coloration/discoloration ability exists in smart windows, not conducive to optical‐electrical coupling and leap in performance. Substituting for common composites utilized in smart windows, here, single transparent ceramic‐based smart windows are reported through composition design and defect management strategies to regulate the optoelectronic performances and break off the contradictions between optical transmittance, photo‐thermochromism and electrical conductivity. By first principles calculations and precisely tuning Er3+, Ba2+, Sr2+ concentrations in non‐stoichiometric Er‐doped (K0.5Na0.5)NbO3‐(Ba, Sr)TiO3, the fabricated ceramics exhibit brilliant transparency and multi‐mode dramatical and reversible modulations of pellucidity, photoluminescence intensity, along with conductivity (over fivefold variation), enabling prominent optoelectronic information storage and modulating capacity in vivid potential applications, such as easy‐readout/erasable optical memorizers, photo‐memristors and anti‐counterfeiting displays. [ABSTRACT FROM AUTHOR]