according to the chemiosmotic hypothesis, what provides the energy that directly drives atp synthesis?

According to the chemiosmotic hypothesis, the energy that directly drives ATP synthesis is provided by the proton gradient (also called the proton motive force) across the membrane. This gradient is created by the movement of protons (H+ ions) from a region of high concentration to a region of lower concentration through ATP synthase. The flow of protons back across the membrane through ATP synthase provides the energy needed to convert ADP and inorganic phosphate into ATP. The proton gradient represents stored potential energy generated by the electron transport chain pumping protons across the membrane. The return flow of protons through ATP synthase releases this energy and drives the mechanical rotation of ATP synthase to produce ATP. This mechanism was proposed by Peter D. Mitchell and has become the accepted explanation for ATP synthesis in mitochondria, chloroplasts, and many bacteria.