Emerging technologies in water desalination: A review and future outlook

• Emerging desalination technologies for sustainable water solutions are analysed. • New advancements in SED, SCDI, SPPD, CDI-HS, MD, and FO technologies are evaluated. • Key challenges in desalination and future research directions are identified. • Improvements in solar energy efficiency, materials, and energy recovery are noted. • Innovative solutions for efficiency, scalability, and sustainability are proposed. This review analyses emerging desalination technologies that offer sustainable solutions to global water scarcity and address unresolved issues. This study examines solar electrochemical distillation (SED), integrated solar capacitive deionisation (SCDI) and capacitive deionisation hybrid systems (CDI-HS), solar-powered passive desalination (SPPD), membrane distillation (MD), and forward osmosis (FO). A comprehensive literature review evaluates recent research and advancements in each technology. From each study, the authors extracted key characteristics, including the year of publication, research methods, data collection techniques, and the direction or strength of the research outcomes. Each study in this review serves as a unit of analysis, with the literature forming a database to interpret trends and draw conclusions about emerging desalination technologies. Key challenges were identified, and recommendations for future studies proposed, based on existing data and experimental findings. The review's findings underscore the need to address unresolved issues in desalination technologies to enhance their efficiency, scalability, and sustainability. Implementing the recommended research strategies could optimise these technologies, ensuring a reliable and sustainable supply of fresh water. Continued innovation, supported by targeted research and robust policy frameworks, is essential to mitigate global water scarcity and ensure water security for future generations.