Formation and thermal stability of step edges on TiO2(110) Electronic structure of ZnS on ZnO substrate 1. Formation of step edges by ion irradiation 2. Thermal stability Increased ion fluence 700 oC Figure caption: (a) valence band spectrum for ZnO with increasing sulfur exposure. A band gap narrowing is observed due to formation of sulfur derived band gap state. This state is clearly discernable in the difference spectrum. (b) STM image of the 2D ZnS growth on ZnO. (c) schematic interface band-alignment as measured at NSLS and proposed photo excitation and reaction at this novel hybrid material.