If you do take interest in the burgeoning field of solar-based technological applications, chances are that you are not unfamiliar with perovskite – the touted ‘wonder material’ with effective light-absorbing properties. But this time around, scientists at the École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland, have seriously notched it up a level by developing nanowires from the much heralded perovskite material. In essence, the newly contrived technology combines the advantage of the perovskite and the efficiency of nanomaterials (that have been previously demonstrated to have competent photovoltaic properties).
Interestingly, the tech was developed when one of the scientists Endre Horváth, was attempting to grow nanostructures from the liquid form of methylammonium lead iodide – which belongs to the class of perovskite. This specific perovskite compound potentially has a high energy quotient, and hence can be used for applications like dye-sensitized solar cells. However, during the initial phase of the experiment, the EPFL researchers were only able to produce macroscopic crystals of various shapes, ranging from needles to cubes. But after that – they successfully reduced the crystal-sizes to a microscopic ambit, and finally to a nanoscale.
Buoyed by this success rate, the scientists hatched the notion of transforming the nanocrystals (of the perovskite) into nanowires that might enhance the efficiency of photovoltaic materials. For the procedure, they tried out the conventional technique of what is known as ‘blade-coating’. This texturing process was unsuccessful, and so the researchers moved on to a new ‘indigenous’ technique that entailed the pressing of the perovskite nanocrystals between two glass coverslips (used for microscopes). The coverslips were then slid apart, which led to the creation of needle-like structures that were observable within a few seconds.
The diameters of these ultra-thin components were found to match the nanoscale, thus resulting in the formation of perovskite nanowires. To that end, the original lab technique has been dubbed as ‘slip-coating’. And now, the EPFL scientists are looking forth to standardize this procedure, so that the technique for producing perovskite nanowires can be replicated in other labs and industrial facilities. This is what Horváth had to say about the potential applications of the newly-developed nanomaterial –
If we can make nanowires like this, it will open up a whole new sub-field of technology, where we can make a number of optical tools, such as detector antennas, lasers or diffraction gratings.
The video shows the lab-achieved transformation of perovskite crystals into nanowires –
Image Credit: EPFL