Transition metal chalcogenides as emerging triboelectric materials for high-performance energy harvesting devices

Abstract

The search for efficient, stable, and positive triboelectric materials is urgently needed to advance triboelectric nanogenerator (TENG) technology. Addressing this gap not only enhances device performance but also supports broader sustainability objectives, aligning with SDG-driven efforts toward clean energy, innovation, and responsible material use. While progress has been made with many negative triboelectric materials, the development of their positive counterparts remains limited. Therefore, bridging this gap is essential for achieving higher efficiency TENGs. In the present work, we propose transition metal chalcogenides (TMCs), specifically vanadium tetrasulfide (VS4), as a new tribopositive material for the first time. The positive triboelectric nature of VS4 is experimentally verified with simple electrostatic interaction tests, surface potential values and TENG-based tests. The VS4-based TENG achieves an open-circuit voltage of ∼1.52 kV, a short-circuit current of ∼180 mA, a transferred charge of ∼200 nC, and a power density of 14.45 W m−2 under biomechanical hand-tapping force. The obtained performance is the highest among the sulphur-TMC-based TENGs reported to date. This high performance TENG device was capable of powering a series-connected array of 720 light-emitting diodes (LEDs) and 6 LED bulbs. The present findings establish VS4 as a new positive material for the development of triboelectric energy harvesting and self-powered systems.