Temperature dependence of the surface potential distribution on the BaTiO3 (0 0 1) single crystal ferroelectric domain walls was investigated by the scanning Kelvin probe microscopy. After decreasing the single crystal temperature below the Curie point (T-C), high potential (similar to 600 mV) stripes were immediately observed near the 90 degrees a-c domain wall surface. The potential stripes were not stable and decayed with time. The adjacent c domain surface screening charges and their mobility play a dominant role in this experiment. The corrugation topography at the 90 degrees a-c domain wall acts as a natural charge trap and should not be neglected. Besides, the polarization and the strain variations across the wall induce large physical changes of the material. (C) 2014 Elsevier B.V. All rights reserved.