Ultra-robust tribo- and piezo-electric nanogenerator based on metal organic frameworks (MOF-5) with high environmental stability

Isoreticular metal–organic frameworks (IRMOFs) as a subseries of metal-organic frameworks (MOF) have excellent thermal and chemical stability, tuneable porosity, and high surface area as compared to other MOFs. IRMOFs' appealing properties can lead to their usefulness in the fabrication of tribo- and piezo-electric nanogenerators. For the first time, this paper applies metal-organic frameworks (MOF-5 or IRMOF-1) for fabricating tribo- and piezo-electric nanogenerator for energy harvesting. The MOF-5 based tribo-electric nanogenerator (TENG) produces an excellent output performance with the open-circuit voltage of 484 V, short-circuit current of 40 µA, and maximum instantaneous power of 3174 µW. Here, the proposed TENG presents a stable performance under adverse environmental conditions such as temperature and humidity, showing its robustness under harsh environmental conditions. The fabricated TENG device is utilized to charge the various commercial capacitors, power up the light-emitting diodes (LEDs) and drive low-power electronic devices such as a calculator and stopwatch. In addition, the MOF-5 is further studied for fabricating piezo-electric nanogenerator (PENG). The fabricated PENG device with 5 wt% MOF-5 blended in PDMS yields an open-circuit voltage of 27 V, short-circuit current of 2.9 µA, and maximum instantaneous power of 5.76 µW, respectively. Furthermore, the PENG device is utilized to charge the various commercial capacitors and power up the LEDs. These results demonstrate that MOF-5 can be applied for fabricating ultra-robust TENG for a harsh environmental condition, and also an effective way towards piezo-electric nanogenerators.