A “Green” Reaction Cycle Pathway for Synthesizing Metal Oxide Quantum Dots
Authors: Padmanaban Dilli Babu , McGlynn Ruairi , Maguire PAUL , Mariotti Davide 
Published: September 2023

Synthesis of highly stable quantum dots (QDs) is always a challenge for researchers in nanomaterial community because of involved complexities of the process time and steps. In the past few years, we have demonstrated a simple and single step synthesis process for a range of metal oxide (MO) QDs using plasma-induced non-equilibrium electrochemistry (PiNE).1
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3 PiNE is a new and emerging technique based on electrochemical process taking place in liquids from plasma interaction.4 This method is rapid and produces highly stable QDs starting from a metal foil and ethanol as electrolyte. As MO QDs semiconductors in general are a promising candidate for energy harvesting application mainly from their nanoscale effects.5
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6 In this work, we will present the general applicability of this method for a range of metal oxides and the provide more an in-depth case study for CuO QDs providing details of the reaction mechanisms. An extensive analysis of the solution along with the quantum dots was carried out with nuclear magnetic resonance (NMR) spectroscopy and gas chromatography-mass (GC-MS) spectroscopy, Fourier transform infra-red spectroscopy (FTIR) and ultraviolet-visible (UV-Vis) spectroscopy, pH and the plasma-ethanol interface using optical emission spectroscopy. Thus, the study discloses important aspects of plasma interactions with a non-aqueous medium particularly the trace products and QD purity shows the entire process is a ‘green’ synthesis cycle.7

Reference

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