Developing a highly efficient fluorescent sensor for detection of trace amounts of nitro explosives remains a great challenge. Porous metal-organic frameworks (MOFs) are one class of promising fluorescent sensors towards small molecules. Herein, we constructed an anionic Zn-based MOF FJI-C8 based on pi-conjugated aromatic ligand H(6)TDPAT (2,4,6-tris(3,5-dicarboxylphenylamino)-1,3,5-triazine) containing nitrogen rich sites. On account of the high density of uncoordinated N atoms, the high overlap between the emission spectrum of the anionic MOF FJI-C8 and the UV-vis absorption spectrum of the representative nitro explosive 2,4-dinitrophenol (2,4-DNP), and the porosity of the MOF, FJI-C8 is demonstrated to be an excellent chemosensor for 2,4-DNP with fast response time (less than 30s), high selectivity (K-sv = 5.11 x 10(4) M-1 for 2,4-DNP), extra sensitivity (LOD = 0.002866 mM for 2,4-DNP), low usage amount (0.04 mg/mL), good stability and quantitative detection features. To the best of our knowledge, this is the first example for highly selective detection of 2,4-DNP. More importantly, theoretical calculation and control experiments unveiled that the energy transfer is the main mechanism for highly detection of 2,4-DNP. This work will pave the way for designing highly efficient luminescent chemosensors. (C) 2017 Elsevier B.V. All rights reserved.