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Carbon dots (CDs) have been attracted considerable attention due to their interesting and unique physical and chemical properties.Unfortunately, the fluorescence intensity of CDs is relatively low in most reports, metal (such as gold or silver) has been widely used to enhance fluorescence intensity, as known as metal-enhanced fluorescence (MEF).Herein, Ag enhanced fluorescence of carbon dots have been successfully prepared by a simple and facile process.The largest enhancement factor (EF) appeared when incorporation of the silver nanoparticles (NPs) at a concentration of 2.27mg/L(0.8ml).The as-synthesized Ag-CDs composites were characterized using ultraviolet-visible spectroscopy, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and Fluorescence spectra(PL).In this case, the MEF mechanism may be predominantly derived from the localized electric field effect ofAg NPs and partly from the plasmon coupling effect inducing by the SPR absorption of Ag NPs and the emission Ag-CDs.Moreover, Ag-CDs composites were used to obtain a film, which were adopted to fabricate CD-based white light-emitting diodes (W-LEDs) by combining the yellow light-emitting Ag-CDs film with blue GaN-based LED chips.The as-assembled W-LEDs exhibited the optimised colour coordinates of (0.3340, 0.3453), the colour rendering index(CRI) up to 74.6, the correlated color temperature of 5435K.Such superior optical merits endow them with promising potentials in optical devices.