Researchers from Flinders University have developed a novel and environmentally friendly method for producing various types of gold nanoparticles using a vortex fluidic device (VFD) and water, without the need for toxic chemicals.
The study, published in the journal Small Science, details how the team, led by PhD student Badriah Mazen B Alotaibi, was able to synthesise pure, pristine gold nanoparticles by adjusting the water flow and processing parameters within the VFD.
“Through this research, we have discovered a new phenomenon in the vortex fluidic device. The photo-contact electrification process at the solid-liquid interface which could be used in other chemical and biological reactions,” Alotaibi said.
“We also have achieved synthesis of pure, pristine gold nanoparticles in water in the VFD, without the use of chemicals commonly used — and thus minimising waste.”
The green chemistry approach not only eliminates the need for toxic chemicals but also offers a quick, scalable, and sustainable method for producing nanomaterials with unique properties.
The size and shape of gold nanoparticles are crucial for various applications, including drug delivery, catalysis, sensing, and electronics, due to their physical, chemical, and optical properties.
“This method is significant for the formation of nanomaterials in general because it is a green process, quick, scalable and yields nanoparticles with new properties,” Alotaibi added.
The vortex fluidic device, invented a decade ago by Flinders University Professor Colin Raston, is a rapidly rotating tube open at one end, with liquids delivered through jet feeds.
By adjusting the rotational speeds and applying external light, researchers can synthesise particles with specific characteristics.
“Researchers around the world are now finding the continuous flow, thin film fluidic device useful in exploring and optimising more sustainable nano-scale processing techniques,” Raston said.
“In this latest experiment, we hypothesise that the high shear regimes of the VFD led to the quantum mechanical effect known as contact electrification, which is another exciting development.”
Raston emphasised that this discovery represents a paradigm shift in how materials can be made in a controlled way using water, with no other chemicals required, contributing to a more sustainable future.
The research team’s findings have been published in the article “Nanogold Foundry Involving High-Shear-Mediated Photocontact Electrification in Water” in the journal Small Science.