<p>The increasing demand for Internet of Things (IoT) devices has revolutionized multiple industries but it has also raised significant concerns about electronic waste and energy consumption. Energy harvesting (EH) presents a sustainable alternative by enabling self-powered electronic systems that reduce battery dependence and minimize environmental impact. This paper provides an overview of the current trends in EH technologies, including key energy sources as well as advancements in sustainable materials and fabrication techniques like printed electronics. Challenges related to power efficiency, energy storage, and the variability of energy availability are examined, while hybrid EH systems and reconfigurable electronics are discussed as promising strategies to enhance energy capture and power management. By integrating advances in materials, design, and energy optimization, EH technologies are expected to play a crucial role in the development of sustainable and self-sufficient IoT ecosystems.</p> Graphical abstract <p></p>