photocatalyst
Quick Summary
A photocatalyst is a substance that speeds up a chemical reaction when exposed to light. A key example is titanium dioxide, discovered by Akira Fujishima. When titanium dioxide is exposed to light, it can cause water to decompose into hydrogen and oxygen.1
While this process showed little promise as an energy source, photocatalyst technology has found applications in surface coatings for glass and tile, providing water and bacteria repellency. It is also being explored for breaking down environmental pollutants. Photochemical reactions are initiated by absorbing light energy, creating excited states that have different chemical properties than the original molecules. This principle is fundamental to processes like photosynthesis.12
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- Fujishima Akira
…titanium dioxide, acts as a photocatalyst—a substance that facilitates a chemical reaction when it is exposed to sunlight. In their experiments titanium dioxide exposed to light caused water to decompose, producing hydrogen and oxygen. This discovery gained worldwide attention as the “Honda-Fujishima effect” after it was reported in a 1972…
Read More…titanium dioxide, acts as a photocatalyst—a substance that facilitates a chemical reaction when it is exposed to sunlight. In their experiments titanium dioxide exposed to light caused water to decompose, producing hydrogen and oxygen. This discovery gained worldwide attention as the “Honda-Fujishima effect” after it was reported in a 1972…
Read More - Honda Kenichi
…titanium dioxide, acts as a photocatalyst—a substance that facilitates a chemical reaction when it is exposed to sunlight. In their experiments titanium dioxide exposed to light caused water to decompose, producing hydrogen and oxygen. This discovery, which gained worldwide attention as the “Honda-Fujishima effect” after it was reported in a…
Read More…titanium dioxide, acts as a photocatalyst—a substance that facilitates a chemical reaction when it is exposed to sunlight. In their experiments titanium dioxide exposed to light caused water to decompose, producing hydrogen and oxygen. This discovery, which gained worldwide attention as the “Honda-Fujishima effect” after it was reported in a…
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