Development of low-cost, highly efficient catalysts for water splitting is required to replace precious metal catalysts. CeO (x) -modified CoP@carbon composites are prepared via Ce-doped metal-organic frameworks. The as-prepared CeO (x) -modified CoP@carbon composites have excellent electrocatalytic activity with respect to the oxygen evolution reaction, for which an overpotential (eta) up to 313 mV is achieved at the current density of 10 mA cm(-2). In addition, CeO (x) -modified CoP@carbon composites show an overpotential of up to 127 mV at the current density of 10 mA cm(-2) for the hydrogen evolution reaction, showing excellent catalytic activity for water splitting.