POM-based compounds as capacitor materials and their photoelectric-sensing properties toward inorganic ions

Abstract

By using different transition metal ions three isostructural Anderson based compounds were obtained, [M2 II(H3bdpm)2TeMo6O24(H2O)6] (M = Co (1); Cd (2); Zn (3)). Compounds 1-3 can act as photoelectric sensors for detecting inorganic ions. As electrochemical sensors, 1 and 2 can detect nitrite with excellent sensitivity and wide concentration range; 2 exhibits better electrochemical properties than 1, with response time of 2.16 s, sensitivity of 43.10375 μA mM−1 and detection limit of 5.11 × 10−5 M. As fluorescent sensors, 1-3 can detect Cr2O7 2– with low concentration. Furthermore, the capacitor performances of 1-3 were explored, in which 3 shows the highest specific capacitance (409 F g−1 at 1 A g−1 with 80% of cycle efficiency after 1000 cycles).