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Amplification of the intensity and dissymmetry factors (glum) of circularly polarized light is desired to broaden the range of applications of circularly polarized luminescence (CPL) because of the small glum values commonly observed for CPL materials and the loss of intensity resulting from circular polarization. In this study, enhanced CPL produced by metal‐enhanced fluorescence is successfully achieved by the self‐assembly of Au@SiO2 triangular nanoprisms (Au@SiO2TNPs) and fluorophores (sulforhodamine 101 and methylene blue) in chiral cellulose nanocrystal films. By overlapping the plasmon bands of Au@SiO2TNPs and the excitation–emission spectra of fluorophores, both the fluorescence intensity and glum value of CPL are significantly enhanced. For sulforhodamine 101 in the metal‐enhanced CPL system, a 52‐fold fluorescence enhancement is achieved, and the glum value increased from −0.038 to −0.126. For methylene blue in the metal‐enhanced CPL system, a 201‐fold enhancement of fluorescence is obtained, and the glum value is enhanced from −0.055 to −0.085. This metal‐enhanced CPL film is expected to generate superior circularly polarized light for extensive CPL applications because of its outstanding enhanced CPL, fluorescence amplification, and feasibility for different fluorophores.

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Circularly polarized (CP) light has attracted wide attention for its great potential in broad applications. However, it remains a challenge to generate left-handed and right-handed circularly polarized (LCP and RCP) light from cellulose nanocrystal (CNC)-based materials only with an intrinsic left-handed chiral structure, owing to the pattern of CP light emission primarily based on the chirality of materials. Herein, a separation structure of luminophore layers and chiral CNCs was provided to achieve dualmode CP light emission by building a luminophore−chiral CNC interface. By directly exciting the back and front of two-layer films, LCP and RCP light could be easily emitted without any assisting means and specific setting angles. In addition, owing to the formation of the luminophore−chiral CNC interface, metal-enhanced fluorescence (MEF) was achieved to offset the brightness loss caused by circular polarization. By incorporating gold triangular nanoprisms in CNC chiral layers, the fluorescence enhancement of the ensemble was as high as 6.5-fold. The decisive role of the luminophore−chiral CNC interface in enhancing luminescence and dual-mode CP light emission was carefully investigated by contrasting the systems with and without luminophore−chiral CNC interfaces in this study. We believe that this dual-mode CP light emission film with MEF enables a promising approach to extending the application of CP light materials.

The dye-sensitized solar cell (DSSC) is one candidate among the third-generation solar cells. The performance of most DSSCs based on TiO2 photoanode was limited by the low electron mobility within TiO2. To produce a much higher power conversion efficiency, Sn-doped TiO2 nanowire arrays were successfully prepared using a simple hydrothermal process. It was found that Sn doping augments electron mobility well and raises the flat band potential to improve the performance of DSSCs. The power conversion efficiency (η) of a DSSC based on the reasonable Sn-doped TiO2, N719 dye, platinized counter electrode and iodide/triiodide electrolyte reaches 8.75%. Furthermore, with an anatase TiO2 light scattering layer, a DSSC based on the Sn-doped TiO2 NWAs exhibits a remarkable power conversion efficiency of 9.43%, which is especially useful in weak light conditions.

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