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Direct growth of NiCo2O4 on 3D textile and wavy carbon cloth (CC) using facile and low-cost electrodeposition results in the creation of distinct morphologies. The homogeneity and conformality of the coating of NiCo2O4 on CC can be readily controlled by adjusting or optimizing the electrodeposition parameters as shown by SEM and TEM images. Various loadings of NiCo2O4 were prepared under different conditions. The electrochemical characterization measurements for the oxygen evolution reaction (OER) show that hierarchical NiCo2O4 on CC has a low onset potential at 270 mV, low overpotential of 290 mV at 10 mA/cm2, and low electron transfer resistance across the electrode and electrolyte. NiCo2O4/CC electrode showed excellent stability when evaluated for ~500 hours. This synthesis method holds high potential for large-scale electrode fabrication on carbon substrates. The method is comprised of controllable optimizing parameters that can readily affect the materials’ catalytic performance.

Corrosion sensors are of critical importance for monitoring the destructive potential of a corrosive environment. Due to their large surface-to-volume area, nanowires react with a remarkably high speed, rendering them attractive corrosion-sensing elements. To avoid the difficulties related to contacting nanowires, we present a magnetic approach, exploiting the fast reaction of nanowires to the environment. Iron nanowires have a high magnetization value, which decreases upon nanowire corrosion. Due to shape anisotropy, they also possess a large remnant magnetization, which is detectable by a magnetic tunnel junction sensor. Iron nanowires were fabricated by electrochemical deposition, placed on top of the magnetic tunnel junction and aligned using a magnetic field. The nanowires provide a bias field causing a change of the characteristic curve of the tunnel junction. The corrosion sensor was tested in