Proof of 'waterfall effect' in photovoltaic cells

To answer the question: 'Does the waterfall effect really exist?' , Dutch scientists have conducted a study to prove the existence of this effect, paving the way for the production of high-power photovoltaic cells.

' Avalanche effect' - created by electrons produced in microscopic and distinctive semiconductor crystals - was first discovered and measured in 2004 by room researchers. Los Alamos national experiment (USA). However, since then, the scientific community has been skeptical about the existence of the waterfall effect.

Recently, the research group of Delft Technical University (Netherlands) has established irrefutable evidence of the cascade effect. In his research, Professor Laurens Siebbeles demonstrated the true cascade effect that occurs in the nanocrystals of lead selenide (lead selenide - PbSe).

According to experts, the application of solar cells is opening up great opportunities for large-scale electricity production in the future. However, significant limitations exist, such as most photovoltaic cells with relatively low capacity (only about 15%) and high production costs.

Professor Siebbeles' team has overcome these limitations by using a form of photovoltaic cells made with semiconductor nanocrystals (measured in nanometers in size). In conventional photovoltaic cells, a photon (light quantum) can only release one electron correctly.

The cascade effect will pave the way for the production of high power photovoltaic cells.(Photos: www.solarnavigator.net)

This free electronic generation is a sign that the photocell works well and is capable of providing electricity. The more electrons released, the higher the photovoltaic cell's capacity.

However, in some semiconducting nanocrystals, 1 photon is capable of releasing 2 to 3 electrons, thereby creating a cascade effect. In theory, this phenomenon can create a maximum capacity of 44% in a photovoltaic cell containing suitable semiconductor nanocrystals. Moreover, the cost of producing these cells is relatively cheap.

By using ultra-fast laser methods to measure accurately and in detail, Professor Siebbeles's research is considered to be more reliable than other studies in this area.

The results of the study by Professor Siebbeles and colleagues will be published in this week's Nano Letters science journal. Mr. Siebbeles believes that this new discovery will pave the way for more extensive discoveries of the cascade effect.

Photovoltaic cells are photovoltaic devices that, when exposed to visible or invisible light (such as infrared rays) on the surface of the electrode, will have a photoelectric effect, thereby producing an electric current. Photovoltaic cell electrode is made of metal (Xesi, Bari, Kali .) or by semiconductor. Today, photovoltaic cells are widely used in light measuring devices, alarm devices, automatic adjustment, photo telegraphy, television cameras and in cinema, etc.