Perovskite-type La1-xSrMnO3 were synthesized at 600degreesC by a sol-gel route involving polyacrylic acid as precursor and investigated as electrocatalysts for the O-2-evolution reaction (OER) in KOH solutions. The oxide powders were produced in the form of films on pretreated Ni-supports by an oxide-slurry painting technique. The study showed that Sr-substitution in the oxide matrix did not influence the oxide roughness significantly. The true electrocatalytic activity of the catalyst decreased with increasing Sr-substitution. The reaction order has been found to be approximately unity in OH- concentration. The Tafel slope values at low potential ranged between similar to 103 and similar to 116 mV decade(-1). The rate of OE increased with increasing temperature following the Arrhenius law. Sr-substitution of 0.4 mol reduced the electrochemical activation energy (DeltaH(cl)(#0)) for OE by 12.9 kJ mol(-1). (C) 2002 International Association for Hydrogen Energy. Published by Elsevier Science Ltd. All rights reserved.