A novel multi-metal oxide nanocomposite, Ag 2 O$SrO$CaO, was synthesized by a facile co-precipitation method followed by calcinations. The synthesized nanocomposite was characterized by XRD, FESEM, EDS, TEM, FTIR spectroscopy and photoluminescence (PL) spectroscopy. The composite showed enhanced photocatalytic activity under visible light irradiation and excellent anti-bacterial performance against both Gram-positive and Gram-negative bacteria. Here, the synthesized Ag 2 O$SrO$CaO nanomaterials were deposited on a glassy carbon electrode (GCE) in the form of a thin film to fabricate the desired electrochemical sensor and subjected to I-V analysis of 3-chlorophenol (3-CP) in a phosphate buffer solution (PBS). A calibration curve was plotted from the linear relation of current versus concentration and used to calculate the sensitivity (8.9684 mA mM À1 cm À2 ), linear dynamic range (LDR, 0.1 nM to 0.01 mM) and lower limit of detection (DL, 97.12 AE 4.86 pM). The analytical parameters of the sensor such as response time, reproducibility and long-term stability in the detection of 3-CP were reliable. Finally, it was used to analyze real samples collected from various environmental sources and found to be acceptable.

Photocatalytic dye degradation efficiency of Ag·NiMn2O4 at pH 4 was 91%; at pH 9, 77% and 95% in presence of H2O2 and at pH 7, 50%. Assembled Ag·NiMn2O4 nanomaterials/binder/GCE, as m-THyd sensor showed considerable sensitivity, DL, LDR, response time, reproducibility etc.