Binder-free NiFe-based electrocatalyst with aligned pore channels has been prepared by freeze casting and served as a bifunctional catalytic electrode for oxygen and hydrogen evolution reaction (OER and HER). The synergistic effects between Ni and Fe result in the high electrocatalytic performance of porous NiFe electrodes. In 1.0 M KOH, porous Ni₇Fe₃ attains 100 mA cm⁻² at an overpotential of 388 mV with a Tafel slope of 35.8 mV dec⁻¹ for OER, and porous Ni₉Fe₁ exhibits a low overpotential of 347 mV at 100 mA cm⁻² with a Tafel slope of 121.0 mV dec⁻¹ for HER. The Ni₉Fe₁//Ni₉Fe₁ requires a low cell voltage of 1.69 V to deliver 10 mA cm⁻² current density for overall water splitting. The excellent durability at a high current density of porous NiFe electrodes has been confirmed during OER, HER and overall water splitting. The fine electrocatalytic performances of the porous NiFe-based electrodes owing to the three-dimensionally well-connected scaffolds, aligned pore channels, and bimetallic synergy, offering excellent charge/ion transfer efficiency and sizeable active surface area. Freeze casting can be applied to design and synthesize various three-dimensionally porous non-precious metal-based electrocatalysts with controllable multiphase for energy conversion and storage.

已通过冷冻铸造制备了具有对齐孔道的无粘合剂 NiFe 基电催化剂，并用作氧和氢析出反应（OER 和 HER）的双功能催化电极。Ni和Fe之间的协同作用导致多孔NiFe电极的高电催化性能。在 1.0 M KOH 中，多孔 Ni ₇ Fe ₃在 388 mV 的过电势下达到 100 mA cm ^-2，OER的 Tafel 斜率为 35.8 mV dec ^-1，而多孔 Ni ₉ Fe ₁在 100 时表现出 347 mV 的低过电势mA cm ^-2具有 121.0 mV dec ^-1的塔菲尔斜率（HER）。Ni ₉ Fe ₁ //Ni₉ Fe ₁需要 1.69 V 的低电池电压才能为整体水分解提供 10 mA cm ^-2电流密度。在 OER、HER 和整体水分解过程中，多孔 NiFe 电极在高电流密度下具有出色的耐久性。由于三维连接良好的支架、对齐的孔道和双金属协同作用，多孔镍铁基电极的优良电催化性能，提供优异的电荷/离子转移效率和相当大的活​​性表面积。冷冻铸造可用于设计和合成各种具有可控多相的三维多孔非贵金属基电催化剂，用于能量转换和存储。