https://doi.org/10.1351/goldbook.13992
Quantities expressed in terms of "per area" are denoted as area-related parameters.
Notes:
- In photocatalysis, the area-related parameters do not characterise the catalyst as they do in heterogeneous dark catalysis. In general, the properties of a photocatalyst are not directly proportional to its area, especially in view of the fact that light may not equally reach every part of the surface of a particle. The light may not enter the pores of a porous surface and in this case only the outer area behaves as catalyst. A similar situation may occur when particles are aggregated.
- When the surface area that is accessed by the light cannot be established, it is recommended to use the total surface area in terms of the \(\rm{BET}(\ce{N2})\) area. This implies that most probably a lower limit of the quantity is obtained, because the surface determined by \(\ce{N2}\) adsorption will be larger than that reached by the radiation.
See: BET(N2) area