Ultrathin near-infrared transmitting films enabled by deprotonation-induced intramolecular charge transfer of a dopant

Near-infrared transparent films demonstrate important applications in many fields, but how to eliminate light interference from ultraviolet-visible region and how to tackle the trade-off effect between film thickness and transmittance remain as challenges. Herein, we report a near-infrared transparent film that achieves high-efficient combination of thin thickness (16 μm), suitable cut-off wavelength (890 nm), and ideal transmittance (T