Multi-responsive luminescent MOF sensor for Fe3+, CrO42− and Cr2O72− in aqueous solution based on phenylenediacetate and bis-imidazole ligand

•New metal-organic frameworks based on carboxylic acid ligand and nitrogen-containing ligand were presented.•The selective detection for Fe3+ and Cr6+ species in aqueous solution were investigated.•The quenching mechanism of the selective detection was presented.