• TENG technology offers a lightweight, cost-effective, and efficient solution for harvesting low-frequency marine energy, addressing limitations of traditional electromagnetic generators.
• The review systematically categorizes recent TENG designs for marine energy harvesting, highlighting advances in structural design and power take-off mechanisms.
• Integration of TENG with in situ electrochemistry enables sustainable production of clean fuels and water treatment, opening new avenues for blue energy utilization.
• Key challenges such as durability, scalability, and system integration are identified, with proposed solutions to accelerate commercialization.