Study of Piezo-related Properties of Heterostructured C3N4/ZnSnO3 Nanocomposites

Abstract

Zinc tin oxide (ZnSnO3 ZTO) nanowire arrays were prepared through hydrothermal synthesis It was coupled with C3N4 (melon) to form a heterogeneous nanocomposite as a catalyst material In this study two types of ZTO-C3N4 nanowire composite arrays were fabricated One was fabricated by spin coating thermally condensed C3N4 on ZTO nanowire arrays (CN1) The other was developed by immersing ZTO nanowire arrays into C3N4 solutions which was hydrothermally treated after the thermal condensation (CN2) Photodegradation photoelectrochemical (PEC) water splitting and piezo-related applications of the systems were investigated XRD analysis ascertained the fabrication of ZTO in the composite samples of CN1 and CN2 The presence of melon in composites was not observed because of the poor crystallinity and minor amounts of melon Both ZTO and melon were observed in CN1 and CN2 through SEM images ZTO nanowires were further ascertained by cross section SEM and TEM images The particle size of hydrothermally treated melon was smaller than as-synthesized melon obtained from thermal condensation Melon in CN1 and CN2 was also ascertained through Raman and optical measurements From UV-vis results CN1 and CN2 exhibited absorption edges towards the visible light range This was attributed to the presence of melon The Schottky contact behavior of ZTO nanowire arrays was observed through I-V measurements The piezotronic feature was ascertained However no improvement of piezotronic effect for the samples of CN1 and CN2 The photocatalytic performance of ZTO could be enhanced by coupling with melon in the samples of CN1 and CN2 It was due to the improvement of separation of electrons and holes The sonophotodegradation of ZTO and CN2 was explored by applying an ultrasonic vibration to the samples under illumination Both ZTO and CN2 exhibited the enhanced degradation performance The enhanced catalytic activity was attributed to increased availability of ZTO nanowire active sites because of ZTO nanowire surface sweeping

Date of Award	2019
Original language	English
Supervisor	Kao-Shuo Chang (Supervisor)