Systematic literature review of wave energy harvesting using triboelectric nanogenerator

Ocean wave energy is an abundant and promising source of renewable energy but challenging to harvest due to its low frequency and irregularity. Triboelectric nanogenerators (TENGs) are an emerging technology that is highly efficient at harvesting low-frequency energy. Over the last decade, much research has been devoted to wave energy harvesting using TENGs. This study aims to analyse extensive research using the bibliometric approach and discuss state-of-the-art technology in the context of TENGs. The study reviewed articles on wave energy harvesting using TENGs from the Web of Science database from 2012 to 2023. A research topic can be divided into research clusters based on its major categories, and three research clusters were identified in this study, including (A) triboelectric nanogenerator(s), energy harvesting, and blue energy; (B) mechanical energy, system, and conversion efficiency; and (C) performance, contact-electrification, and power. Additionally, research sub-clusters indicate the current research focus in the area, and four sub-clusters were identified: (1) wave energy harvesting with triboelectric nanogenerator, (2) hybrid triboelectric-electromagnetic nanogenerator, (3) harvesting water wave energy, and (4) large-scale wave energy harvesting. According to the results, large-scale wave energy harvesting with TENGs has attracted substantial research attention and is expected to grow in future. In this study, a comprehensive review of wave energy harvesting technology evolutions using TENGs, and their challenges and future prospects is performed that provides a deeper understanding of state-of-the-art technology. This study will help new studies understand wave energy harvesting using TENGs landscape and provide a basis for further research.