A Soft Chemistry‐Based Route to Near‐Infrared Luminescent Bismuth‐Activated Glass Films

Near-infrared (NIR) luminescent materials activated by bismuth are of fundamental and technological importance because of a broad diversity of high-value applications for optical telecommunications and biomedicine. The preparation of Bi-activated films commonly relies on the physical vapor deposition technique including cosputtering and pulse laser deposition. Such conventional methods consist of the preparation of targets, exploring various preparation parameters using expensive experimental apparatuses, and in situ or postthermal treatment of the as-prepared films. Here, we report on a soft chemistry-based approach for the fabrication of NIR luminescent bismuth-activated glass films. The resulting films demonstrate ultrabroad, long-lived photoluminescence in the range 950–1500 nm. This approach is very flexible, permitting the selection of unusual combinations of active centers to tailor functionality. This strategy greatly enriches the techniques for the preparation of bismuth-activated films, providing great promise for the realization of waveguide-type optical amplifiers and lasers.