Methods of forming a cutting element include disposing a volume of polycrystalline material adjacent a liquid electrolytic solution and applying an electrical between the polycrystalline material and a cathode in contact with the liquid electrolytic solution to increase an oxidation state of the metal catalyst material. The polycrystalline material includes interbonded grains of hard material and metal catalyst particles in the interstitial spaces between adjacent grains of hard material. Some methods include forming a barrier over a portion of a surface of a volume of polycrystalline material.