Golden sandwich

Scientists at the Research Institute for Electronic Sciences at Hokkaido University have created what they call a “golden sandwich,” a photoelectrode that captures 85% of sunlight used to split water to produce hydrogen. Yes, it’s experimental, and no, it hasn’t hit commercial production yet. But think for a minute what that might mean for renewables.

This breakthrough by Hokkaido University increases renewable energy production as it is 11 times more efficient than current systems. Of course, we don’t know the price of commercial versions of this technology, but imagine getting 11 times more clean energy from a photoelectrode.

What is the secret of the golden sandwich? A titanium dioxide film only 30 nanometers thick with a 100 nanometer thick gold film on one side and gold nanoparticles on the other. When sunlight hits the side of the nanoparticle, the gold film below acts like a mirror that traps the light in the cavity between the two layers of gold. This helps the nanoparticles to absorb more of the available light, which is crucial for this surprisingly high energy conversion factor.

In an article about this discovery published by Nature NanotechnologAnd researchers claim that gold nanoparticles exhibit a phenomenon known as localized plasmon resonance, which absorbs a certain wavelength of light.

Our photoelectrode has successfully created a new condition in which the plasmon and visible light trapped in the titanium oxide layer interact strongly, allowing light with a wide range of wavelengths to be absorbed by the nanoparticles. ‘gold.“Says Hiroaki Misawa, lead author of the study.”The efficiency of light energy conversion is 11 times that of those without light trapping functions.

Hydrogen could become a major player in the clean energy of the future, but most of the hydrogen commercially available today is derived from transformed natural gas, which is itself a product of fracking. . Hydrogen, as long as it depends on extracting natural gas by unnatural means, is an energy source that we cannot consider clean.

The researchers conclude their report by saying: “Using very small amounts of material, this photoelectrode enables efficient conversion of sunlight into renewable energy, contributing to a more sustainable society.“.

Hopefully, these kinds of technologies can be put into mass production soon, because our planet needs them.

More information: global.hokudai.ac.jp