<p>An electrolytic cell includes at least one free-standing diamond electrode and a second electrode, which may also be a free-standing diamond, separated by a membrane. The electrolytic cell is capable of conducting sustained current flows at current densities of at least about 1 ampere per square centimeter. A method of operating an electrolytic cell having two diamond electrodes includes alternately reversing the polarity of the voltage across the electrodes.</p>
