ARTICLEa basic function to increase the strength of the interaction photocatalyst-pollutant. On the basis of the discussed theoretical considerations, the origin of the high acidity of Bi 2 WO 6 was attributed to the presence of specific sites located onto the lateral faces of platelets. Future work has to focus to control the morphology of platelets to increase the proportion of lateral faces.' ASSOCIATED CONTENT b S Supporting Information. For more details about MU-SIC calculations, the affinity constants and charge of surface groups for planes (100), ( 001), (101), and (10-1) are exposed here. This material is available free of charge via the Internet at http://pubs.acs.org.