Chiral inorganic nanostructured BiOCl co-doped with Er3+/Yb3+ exhibits circularly polarized luminescence and enhanced upconversion luminescence

It has been challenging to develop lanthanides doped chiral inorganic materials that emit circularly polarized light by upconversion. Here, we report the synthesis of bismuth oxychloride based inorganic nanostructured phosphor co-doped with Er3+, Yb3+, modified with chiral sugar alcohols (D-BYE), which exhibited a strong up-conversion circularly polarized luminescence (UC-CPL) property in the visible range. Compared with the achiral bismuth oxychloride phosphor co-doped with Er3+, Yb3+ (A-BYE), D-BYE significantly improved the intensity of upconversion luminescence. Our studies showed that an accelerated rate of radiative transition induced by electromagnetic field and the Mie scattering effect may be responsible for the enhanced upconversion luminescence. Our works provide a new strategy to realize enhanced upconversion of circularly polarized luminescence with rare earth doped chiral inorganic materials.