Synthesis of color tunable piezoelectric nanogenerators using CsPbX₃ perovskite nanocrystals embedded in poly(D,L-lactide) membranes

In recent years, inorganic perovskite materials have emerged as a great potential in optoelectronic and flexible nanogenerator applications. In this study, we have synthesized blue to green tunable photoluminescent (PL) inorganic CsPbX3 (X-Cl/Br) perovskite nanocrystals (NCs) utilizing a heat treatment process at a temperature of 150 C. The purity of the NC's luminescence was analyzed utilizing PL spectroscopy and the pristine blue and green emissions were observed at a 365 nm wavelength under ultraviolet light. Furthermore, the NCs were embedded in a poly(D,L-lactide) (PDLLA) polymer matrix to fabricate flexible blue and green luminous CsPbX3- PDLLA piezoelectric nanogenerators (CPX-PDLLA PENGs). The Fourier-transform infrared spectroscopy char-acterization of both CPX-PDLLA PENG devices further revealed that perovskite NCs were successfully encap-sulated by the PDLLA polymer matrix. The fabricated perovskite based PENGs were tested by hand tapping motion at a 240 beats per minute load frequency to explore the alternating current electrical outputs. The results illustrated that the maximum open circuit voltage and short circuit current obtained for the green PL NCs (g-CPX NCs) incorporated PENG were 1.69 and 1.42 times higher, respectively, in contrast to the blue PL NCs (b-CPX NCs) incorporated PENG. In addition, both b-CPX and g-CPX PDLLA PENGs were tested against a range of resistance and the maximum power output obtained was-335.44 and-797.22 mu W respectively with an active contact area of 31.67 cm(2) for all PENGs. The developed flexible g-CPX PDLLA PENG was able to light up 50 commercial light emitting diodes (1.5 V each) indicating the vast promising applications of the PDLLA-CPX PENG as a soft high-performance self-chargeable device.