Spray‐Coated Inorganic Lead‐Free Double Perovskite Cs₂AgBiBr₆ Based Large‐Scale Triboelectric Nanogenerator for Enhanced Energy Harvesting

Abstract

Low‐cost and efficient large‐scale triboelectric nanogenerator (TENG) is considered as the new scheme for distributed mechanical conversion or renewable energy utilization. An extremely popular all‐inorganic lead‐free double perovskite Cs2AgBiBr6 (CABB) has emerged as extraordinary potential material in triboelectric semiconductors’ substitution, overcoming high‐impedance limitations associated with organic‐polymer‐insulator based materials. In this study, assembled by the certified available positive frictional material CABB, TENG with sandwiched structure of ITO/compact‐TiO2/mesoporous‐TiO2/CABB – the poly‐tetra‐fluoroethylene/Al exhibits appropriate performance on environmental stability and output capacity for which structure can impede charges decay. Fabrication process comparison shows that as an inexpensive large‐scale functional films preparation method, sprayed CABB TENG with brilliant relative dielectric constant and work function difference possess more distinguished output characteristics. This is confirmed by higher open‐circuit voltage of 105 V, larger short‐current density of 2.45 mA m−2 at 0.25 Hz motion parameter, and more abundant output power density of 0.76 W m−2 under 10 Hz. Further study confirms that both higher frequency and larger contact‐area are conducive to total output power, while terminal charging speed is inversely or positively proportional with capacitance or mechanical frequency. Final physical display effect of sprayed CABB TENG lights up at least 53 commercial yellow‐LEDs, holding decent energy conversion ability.