A comprehensive review of nanomaterials for efficient heavy metal ions removal in water treatment

Rapid industrialisation and commercialisation have heightened environmental contamination, with heavy metals as pervasive pollutants from industrial discharges, mining, agricultural runoff, and natural weathering. Due to their non-biodegradable nature and bioaccumulative tendencies, these metals pose serious threats to both human health and the environment. This review explores nanomaterials used for heavy metal ion removal in water treatment, including their characteristics, uses, and environmental impacts. The uniqueness of this study is owed to the extensive comparison of nanomaterials to reveal knowledge gaps of their effects on water chemistry and wastewater characteristics. This scoping review, which followed Arksey and O'Malley's (2005) method, focuses on nanomaterials for heavy metal ion removal in water treatment systems. After screening 4787 citations, 136 publications were included based on their relevance to the research topic and eligibility criteria. The paper also highlights the recent advances of nanomaterial applications recent advances and developments for heavy metal ion removal to improve water quality. The study also proposes multidisciplinary and sustainable futures. This study provides unique insights into water treatment heavy metal ion removal procedures, including pH alterations, ionic composition changes, and suspended particles and organic matter removal. It seeks to improve one's understanding of how nanomaterials address water pollution by focusing on heavy metal ion removal mechanisms, offering unique perspectives on the evolving field and encouraging sustainable and efficient water treatment methods.