Stimuli responsive multicolour fluorescence emission in carbon nanodots and application in metal free hydrogen evolution from water

The present study convincingly demonstrates visible light induced continuous tuning of the fluorescence of carbon nanodots from yellow to cyan within two hours. These carbon dots are well characterized using field emission gun transmission electron microscopy (FEG-TEM), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FT-IR), fluorescence spectroscopy and UV-visible spectroscopy. Moreover, solid state fluorescence of different wavelengths has also been obtained from these colour tunable carbon dots by circumventing the common problem of aggregation induced quenching of fluorescence in the solid state. These carbon dots have also shown a very low band gap and the yellow emissive C-dots have been successfully utilized as a photocathode in metal free photo-electrochemical hydrogen evolution from water.