NiS-modified zeolite imidazolic acid frame-67 as a bi-functional catalyst: A non-enzymatic lactic acid sensor and supercapacitor

The ZIF-67/NiS composite electrode was prepared on nickel foam (NF) matrix by hydrothermal method. NiS has been widely studied in sensors and supercapacitors due to its good electron transfer ability and good pseudocapacitor performance. Therefore, we prepared ZIF-67/NiS composite electrode. The synthesised ZIF-67/NiS composite electrode not only has certain electrochemical performance of battery type electrode, but also is sensitive to lactic acid (LA), and can be used as a non-enzymatic LA sensor and a dual-function material for supercapacitors. The detection limit of LA concentration in alkaline solution is 0.8 μM, and the sensitivity is 1.34 μA μM−1 cm−2. Indicating that the electrode has good electrochemical sensing performance. The GCD test results show that the charging capacity of the ZIF-67/NiS is 2.5 times that of the ZIF-67. The ZIF-67/NiS composite has good cyclic performance, and the capacitance retention rate of the ZIF-67/NiS composite is 87% at 10 A/g current density.