Herein, we report N and S co-doped Carbon quantum dots (CQDs) prepared using palm shell powder (PSP) and triflic acid. The CQDs possessed a graphitic-like structure with narrow size distribution and exhibited a bright green fluorescence. The fluorescent property of CQDs was found to be independent of the excitation wavelength and was used as fluorescence probe for nitrophenols (NPs) with good detection limits (0.079 mu M, 0.165 mu M, 0.082 mu M for NP, DNP and TNP respectively) and linearity in the range 0.2-0.40 mu M, 0.5-85 mu M, 0.20-40 mu M for NP, DNP and TNP respectively.