Facet-dependent photocatalytic properties of Cu₂O crystals probed by using electron, hole and radical scavengers

Abstract

The facet-dependent photocatalytic properties of Cu2O crystals were probed by using electron, hole, and radical scavengers in the photodegradation of methyl orange.

Silicon Wafers with Facet‐Dependent Electrical Conductivity Properties

“…Theo bserved large facet-dependent photocatalytic properties of polyhedral Cu 2 O, TiO 2 ,a nd other semiconductors can be similarly explained, as the efficiency of photoexcited charge migration to external surfaces or heterojunctions strongly depends on the contacting faces. [7][8][9][10][11][12][13] Furthermore,this thin layer with dissimilar band structures for different surface planes also gives rise to the observed facet-dependent optical absorption and emission properties in semiconductor nanocrystals and quantum nanostructures that has been recognized recently. [13][14][15][16][17][18] Since facet effects are observable in many semiconductor materials,i ti s highly interesting to examine possible existence of facetdependent electrical properties of silicon.…”

Density Functional Theory Calculations Revealing Metal‐like Band Structures for Ultrathin Germanium (111) and (211) Surface Layers

“…This model is also very useful to explain widely observed facet-dependent photocatalytic properties of many semiconductor materials and heterostructures, in which photocatalytic activities can vary from highly active to completely suppressed depending on the exposed or contacting facets as seen in Cu 2 Oc rystals and Cu 2 O-ZnOh eterostructures. [9][10][11][12][13][14][15] As the ultrathin layer has dissimilar band structures for different crystal faces it meanst hat light of somewhat differentw avelengths is absorbed by particles of variouss hapes, accounting for the observedf acet-dependent opticalp roperties of Cu 2 Oa nd other semiconductor crystals. [7,11,[16][17][18] To verify that the facet-dependent electrical-conductivity phenomenon is broadly observable in semiconductors, electrical-conductivity measurementsh ave been made on four different faces of Si wafers, which revealed that the (111)a nd (112) surfaces are highly conductive.…”

Silicon Wafers with Facet‐Dependent Electrical Conductivity Properties

“…Such a feature is highly useful for electronic component design. The observed large facet‐dependent photocatalytic properties of polyhedral Cu 2 O, TiO 2 , and other semiconductors can be similarly explained, as the efficiency of photoexcited charge migration to external surfaces or heterojunctions strongly depends on the contacting faces . Furthermore, this thin layer with dissimilar band structures for different surface planes also gives rise to the observed facet‐dependent optical absorption and emission properties in semiconductor nanocrystals and quantum nanostructures that has been recognized recently .…”