Review on the Hierarchical Improvement of Zinc Sulfide-Based Nanogenerator Systems and Their Various IoT Applications

The convergence of energy harvesting and nanotechnology has made great progress in recent years to meet the pressing needs of renewable energy sources. In particular, the recently emerged piezoelectric and triboelectric energy harvesters, also known as nanogenerators, have the potential and advantages to become key players in the Internet of things (IoT) world through heterogeneous integration with energy storage, power management, and microelectronics. To ensure that the fabricated devices are optimized for each application, hierarchical advancements of nanogenerators must be carefully considered, from the most basic steps of material selection to device-level synthesis and applications. Among various inorganic functional materials, zinc sulfide (ZnS) is renowned for its high piezoelectric constant, wide bandgap, versatile nanostructures, photovoltaic, and mechanoluminescent properties, for applications in optoelectronics, LEDs, solar cells, and nanogenerators respectively. The present article delivers a comprehensive review of the latest advances in ZnS-based nanogenerators and their application systems, along with the current research gaps, challenges, and future prospects to provide valuable insights into researchers to propel this field forward by designing more efficient energy-harvesting devices in the future.