https://doi.org/10.1351/goldbook.14036
Ratio of the maximal (typically the initial) rate of photoadsorption of entities \(\ce{B}\) (molecules, atoms, or ions) to the integrated incident (superscript 0, zero) photon flux, \(\int_{\lambda_{1}}^{\lambda_{2}} q_{\rm{p},\lambda}^{0}{\rm{d}}\lambda = q_{\rm{p}}^{0} = {\rm{d}}N_{\rm{p}}^{0}/{\rm{d}}t\), in the wavelength range \(\lambda_{1}{-}\lambda_{2}\). Both rates should be measured under otherwise identical conditions (preferably as initial rates) in order to avoid concentration and/or surface area effects.
Notes:
- Mathematical expression: \[P_{\rm{AE}} = \frac{{\rm{d}}N_{\ce{B}}/{\rm{d}}t}{\int_{\lambda_{1}}^{\lambda_{2}} q_{\rm{p},\lambda}^{0}{\rm{d}}\lambda} \ {\rm{for}}\ t \to 0\] where \({\rm{d}}N_{\ce{B}}/{\rm{d}}t\) is the rate of adsorption of entities (the initial quasi-stationary rate of photoadsorption).
- The initial rate of photoadsorption in SI units is \({\rm{d}}p/{\rm{d}}t\) (\(\pu{Pa s-1}\)) for gas/solid systems, with \(p\) the pressure and in SI-coherent units \({\rm{d}}c/{\rm{d}}t\) (\(\pu{mol L-3 s-1}\)) for liquid/solid systems, with \(c\) the amount concentration of the adsorbate in solution.
- For \(P_{\rm{AE}}\) determined under first-order conditions on photon flux and zero-order on concentration (or pressure), it corresponds to the efficiency of formation of the active photoadsorption centre.