New Trends in Energy Harvesting Through Magnetic Nanofluids

Abstract

The global shift towards sustainable energy solutions has intensified research into advanced energy harvesting systems, with nanofluids – especially their magnetic variants – becoming key materials. This comprehensive study synthesizes bibliometric and scientometric analyses to map the development of nanofluid applications in energy technologies between 2020 and 2025 using tools such as VOSviewer and the Web of Science database. The findings reveal a consistent increase in publications, underscoring growing global interest and collaboration, particularly between countries such as China, India, Saudi Arabia, Pakistan, and Iran. Key thematic groups include: Efficiency and thermal performance: improving the thermal conductivity and heat transfer properties of nanofluids is key to advancing energy harvesting technologies; Energy conversion and photothermal effects: integrating nanofluids into solar collectors and photovoltaic-thermal systems increases their efficiency; Fluid dynamics and optimization: research focuses on viscosity, stability, and system-level optimization for efficient energy transfer; Magnetohydrodynamic, thermoelectric, and thermomagnetic applications: Magnetic nanofluids are increasingly used in systems utilizing magnetohydrodynamics, thermoelectric and thermomagnetic effects (Seebeck and Nernst effects), and the conversion of vibrational energy to transform thermal and mechanical gradients into electricity. Current studies point to the emergence of hybrid and smart magnetic nanofluids with improved stability and long-term performance, offering promising possibilities for thermoelectric devices, waste heat utilization, and motion-based energy harvesting. Despite significant progress, challenges remain in optimizing the properties of nanofluids for industrial applicability and economic viability. This study highlights the transformative potential of nanofluids, particularly magnetic ones, in the development of sustainable technologies through the combination of magnetism, thermodynamics, and nanotechnology.