Recent Developments on I and II Series Transition Elements Doped SnO2 Nanoparticles and its Applications For Water Remediation Process: A Review

The presence of various hazardous toxins such as phenols, phthalates, pesticides, dyes, heavy metals, pharmaceutical waste, etc, is continuously increasing in the water bodies from different agricultural, industrial, and domestic practices, which have brought the toxicity level to an alarming height. Often, these toxic compounds are quite stable in nature and the removal or degradation of these compounds is quite challenging, which further poses a significant threat to the environment. When it comes to enhancing the efficiency of the water purification and decontamination process, SnO2 nanoparticles offer great potential owing to their low concentration and large surface area. Over the past few years, SnO2 nanoparticles as a photocatalyst have garnered huge interest from the research community in the photo-degradation of toxic pollutants present in the water bodies. Among various metal oxides, particularly SnO2 has emerged as the most versatile material for doping of different transition metals due to its plethora of applications such as photocatalysis, energy harnessing, sensors, solar cells, and optoelectronic devices. The pure and doped SnO2 has prominent significance due to its phenomenal catalytic and physicochemical properties such as being chemically stable, inexpensive, and non-toxic. This review explores and summarizes the progress of first and second transition metal series doping in SnO2 for its coherent application toward the degradation of water pollutants. We have emphasized the effect of different transition metal dopants used in the growth of SnO2 nanoparticles based on their synthesis technique, source of irradiation used, nature of contaminations removed, and obtained photodegradation efficiency.