Biosynthesis of high vertically aligned magnesium-zinc oxide nanorods core/shell mediated by pandanus amaryllifolius leaves extract

The previous biosynthesis method, utilizing a one-step approach, resulted in a random distribution or disordered rod structures rather than vertically aligned ZnO nanorods. This drawback limits the optical and electrical efficiency in optoelectronic applications. Hence, a double step approach referring to seed layer development as first step followed by ZnO nanorods deposition as a second step in overall synthesis was highlighted in this study. The study was divided by 4 major sections: (1) preparation of PA leaves extract, (2) preparation of Mg-doped ZnO seed layer on glass substrate and (3) deposition of ZnO nanorods on Mg-ZnO seed layer and (4) synthesization of Mg-doped ZnO nanorods core/shell. The study initially investigated the impact of various preparation techniques of PA extract as a stabiliser on the synthesis of ZnO seed layers. The results indicate that the treated PA (TP) extract greatly enhances UV-Vis absorbance by 194% compared to untreated PA (UP). Mg-doping to ZT (MZT) prepared at pH 7, with 5 w/v% PA, 0.2 M zinc nitrate hexahydrate, and annealed at 350°C further stabilizing the structures, leading to a homogeneous and uniform particle size. The average’s diameter size was found to be 8.13 nm ± 0.91. In the third section, ZnO nanorods grown on prepared MZT using the solution-immersion method are referred to ZZMZT. ZZMZT, primarily hexagonal ZnO with a wurtzite structure, grow perpendicularly to the substrate and show a 290% increase in UV absorption due to enhanced light trapping and nanorod alignment.