Researchers at Flinders University have made a groundbreaking advancement in nanoparticle synthesis by utilizing a vortex fluidic device (VFD) to create a variety of gold nanoparticles through adjusting water flow. This technique eliminates the need for toxic chemicals, promoting a green chemistry approach. The study also uncovered a unique contact electrification reaction in the device, leading to the production of hydrogen and hydrogen peroxide. Published in Small Science, the research showcases the collaborative efforts of Australian and international scientists in tailoring the size and shape of gold nanoparticles based on different VFD parameters and gold chloride solution concentrations. Ms. Badriah Alotaibi, the lead researcher, highlights the discovery of a photo-contact electrification process at the solid-liquid interface, which opens doors for novel chemical and biological reactions. The study emphasizes the significance of synthesizing pure gold nanoparticles in water within the VFD, offering a sustainable and efficient method that minimizes waste. Prof. Colin Raston's invention of the VFD a decade ago revolutionized nanoparticle production by enabling precise control over particle characteristics through rotational speeds and light application. The implications of this research are vast, as the size and shape of gold nanoparticles play a crucial role in various applications such as drug delivery, catalysis, sensing, and electronics, thanks to their unique properties. Prof. Raston underlines the global impact of the VFD in exploring more sustainable nano-scale processing techniques, hinting at a paradigm shift in material synthesis using water without additional chemicals. Overall, this discovery not only advances nanoparticle synthesis techniques but also opens up possibilities for sustainable and scalable production methods, heralding a more environmentally friendly future for material science and nanotechnology.