Colorimetric sensing of heavy metals on metal doped metal oxide nanocomposites: A review

Heavy metal ion-containing pollution has drawn a lot of attention. It presents thoughtful risks to the human situation and environmental system. Nanotechnologies can control, create, and measure objects on a molecular and atomic size between 1 and 100 nm. Their surface area to volume ratio is high. These are the most practical and are to blame for the easy accessibility, particularly for environmental cleanup. The nanocomposites have proven to offer remarkable qualities as platforms for heavy metal detection sensing. Monitoring the water quality is one of the key concerns of researchers in the modern period. Heavy metal contamination is a significant issue and poses a risk to ecological preservation. Due to this, several efforts are being made in present to develop sensitive, quick, and selective sensors. Reversibility, high specificity, and sensitivity are three unique and intriguing characteristics of colorimetric sensors that have grown in popularity. The particular features of nanomaterials, such as those based on metal and metal oxide, polymers, and carbon, make them beneficial for cleaning up the environment. We examined the most recent (2010–2022) advancements in metal composites for the treatment of metal ions in contaminated water in this review study.