Recently, metal oxide nanostructures have seen significant advancements in synthesis and device integration. Considering the sustainability of materials and processes, as well as multifunctionality, zinc-tin oxide nanostructures are among the most promising oxide nanostructures being researched. Their ternary oxide nature allows for impressive multifunctionality, with applications including catalysis, electronics, sensors, and energy harvesting. To synthesize these materials, the use of seed layers can be beneficial since it can influence the growth of nanostructures and is advantageous for applications where nanostructures on film are desired, such as photocatalysis and sensors.

In this work, several seed layers (namely Cu, stainless steel, Cr, Ni, etc.) were tested for the synthesis of ZTO nanostructures. It was generally observed that the structures grown on the seed layers differed from those obtained with the seed-layer-free hydrothermal method (under similar synthesis conditions [1-3]), demonstrating the effectiveness of seed layers in influencing growth. Various types of structures were obtained, such as ZnSnO₃ nanowires and Zn₂SnO₄ nanoparticles, octahedrons, and nanowires. The results suggest a correlation between the phase of the employed seed layer and the resultant phase of the nanostructures. Furthermore, it was generally seen that while shorter times favored the production of nanostructures, longer times resulted in thin films with a nanostructured surface when employing the seed layers [4]. This emphasizes the influence of seed layers on nanostructure growth, not only by inducing the phase but also by accelerating the growth process.

References:

1. Rovisco, A. et al., ACS Appl. Nano Mater. 2018, 1, 3986–3997.
2. Rovisco, A. et al., Nanomaterials 2019, 9, 1002.
3. Rovisco, A. et al., In Novel Nanomaterials; IntechOpen, 2021.
4. Rovisco, A., PhD Thesis, Universidade NOVA de Lisboa, 2019.