Pool Water Pollution: Solving The Chlorine Problem

Swimming in a pool where the chlorine levels are perfect. That's what scientists are aiming for with a new sensor. This isn't your average sensor. It's a cleverly designed electrode. It has a secret weapon: Fe 3 O 4 -Cu-BTC composite. This is mixed with multi-walled carbon nanotubes (MWCNTs) and coated onto glassy carbon electrodes (GCE). This setup is like a super spy for chlorine in water. First, let's talk about the tools used to check the materials. Scientists used a bunch of fancy techniques. These are: field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR),and N 2 adsorption-desorption isotherm. These are like different lenses that helped scientists see the materials in different ways. So, what makes this sensor so special? The electrochemical properties of the Fe 3 O 4 -Cu-BTC/MWCNTs/GC-modified electrode were put to the test. The tests were carried out using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). This is where things get interesting. The test was done in a phosphate buffer solution with a pH of 7. 0. The electrode showed that it could detect free chlorine. The modified electrode is also capable of amperometric detection. It has a linear response in the range of 0. 1 to 400. 0 ppm towards chlorine. The sensor also has a detection limit (LOD) of 0. 0044 ppm (S/N=3). A low limit means it's very sensitive and can control chlorine in swimming pool water. But how does it handle real-world conditions? The sensor was tested for interferences from common ions and dissolved oxygen. The results were impressive. It showed admirable selectivity. This means it can detect chlorine even when other stuff is in the water. The sensor was also tested in real samples of swimming pool water. The results were satisfactory. This new sensor could be a game-changer. It shows that MOF composites could be a promising material for building free chlorine electrochemical sensors in aqueous media.