When a certain amount of energy is absorbed by the catalytic nanoparticle, the energy is consumed for the generation of hot electron-hole pairs due to d-to-s interband and s-to-s intraband transitions. The dominance of either of these two electronic excitations depends on the band structure of the material and the wavelength of excitation. A part of these excited hot-carriers can enhance the reaction at the interface by reducing the Ea (further denoted as 𝐸 ↓ 𝐴𝑐𝑡𝑖𝑣𝑎𝑡𝑖𝑜𝑛 𝑒𝑛𝑒𝑟𝑔𝑦 ). The fate of these hot carriers in case of non-participation in the reaction is thermalization (further denoted as 𝐸 ↑ 𝑇𝑒𝑚𝑝𝑒𝑟𝑎𝑡𝑢𝑟𝑒 ). The balance of the absorbed energy flow (or power), 𝐸 𝑎𝑏𝑠 can thus be expressed as :