Question

What is the importance of the water-splitting reaction for photosynthesis?

Short answer

Water splitting is useful for the hydrogen economy. It produces energy for electron and proton transport and subsequently provides the energy to produce the sugars needed by plants.

Step-by-step solution

Water splitting

The chemical reaction that breaks down water into oxygen and hydrogen is known as water splitting.

${\text{H}}_2\text{O}\to 2{\text{H}}^{+}+\frac{1}{2}{\text{O}}_{\text{2}}+2{\text{e}}^{-}$

Importance of water splitting

A technical breakthrough that might underlie a hydrogen economy would be efficient and cost-effective photochemical water splitting.

Photolysis is a process in which light energy and catalysts combine to divide water molecules into protons (H⁺), electrons, and oxygen gas. The electrons go to chlorophyll, the protons contribute to a proton gradient that powers ATP production, and oxygen is a byproduct. The oxygen-evolving complex, which catalyzes the water-splitting mechanism, is found in photosystems embedded in thylakoid membranes within the chloroplast and contains manganese and calcium.

The exact method by which the enzyme operates is still being discovered; however, it appears to hold water molecules in place while separating protons and electrons and generating oxygen bonds. Many scientists are researching bio-inspired catalysts to develop efficient and cost-effective ways to generate alternate kinds of energy (such as hydrogen fuel) from water splitting,