Abstract
Water scarcity and pollution are significant global challenges impacting human health, the environment, and economic development. Addressing these issues is a priority under the United Nations Sustainable Development Goals. Despite progress, research for sustainable approaches in water resource management continues to evolve. This study investigates the role of nanotechnology in the water sector, focusing on its applications in water purification and addressing challenges in adoption. Expert opinions from 29 participants across diverse regions, including Asia, Europe, North America, and the Middle East, were analysed to provide a global perspective. According to the results of experts, nano catalysts (34.48%) were the most encountered technology, followed by nanofiltration membranes (31.03%), nano-adsorbents (27.59%), and carbon nanotubes (6.9%). While 68.97% of experts are concerned about the potential toxicity of nanomaterials, 20.69% about high operational costs, and 10.34% about higher energy consumption. Over 80% of experts agreed that collaboration among scientists, engineers, policymakers, and industry stakeholders is crucial for achieving sustainable and scalable solutions. The study underscores the need for innovative research to reduce the cost of nanomaterials, improve energy efficiency of processes by developing low-energy nanofiltration membranes, and mitigate toxicity risks through the development of biodegradable or safer-by-design nanoparticles. Furthermore, the findings emphasize the importance of interdisciplinary collaboration and regulatory frameworks to mitigate environmental risks and make nanotechnology more accessible and scalable for industrial and residential applications.