Sample Preparation: The material is first degassed to remove any contaminants or adsorbed gases. Gas Adsorption: Nitrogen gas is adsorbed onto the surface of the material at a constant temperature, usually liquid nitrogen temperature. Data Collection: The amount of nitrogen adsorbed is measured at different relative pressures. Plot and Calculation: A BET plot is generated by plotting 1/[V(P0/P - 1)] against P/P0, where V is the volume of gas adsorbed, P is the equilibrium pressure, and P0 is the saturation pressure. The surface area is then calculated from the slope and intercept of the BET plot.
