The precursor powder mixture for Ni 4 V 3 O 10 was prepared using two methods: high impact mechanical ball milling or hand grinding with an agate mortar and pestle. For samples prepared using ball milling, a total of 2 g of powder of NiO (Alfa Aesar, 99%), V (Strem, 99.5%), and V 2 O 5 (Acros, 99.6%) were mixed under Ar in a stoichiometric ratio based on the chemical equation