Influence of temperature and pressure on preparing Ga nanowire arrays by press-based nanoinfiltration

Nanoscale advanced materials are crucial for technological innovations. Among them, nanowires stand out due to their promising confinement effects and anisotropic properties derived from their elongated structure. However, this class of nanomaterials remains relatively underexploited, primarily due to fabrication challenges. In this work, we implement an alternative method for preparing nanowire arrays by pressing liquid metal into nanoporous alumina templates with cylindrical pores. Gallium was used as the liquid metal due to its melting point near room temperature. An investigation exploring the impact of temperature and pressure on the infiltration factor and length of nanowires was performed, revealing some counterintuitive behaviors. Higher filling factors and longer nanowires were obtained at lower infiltration temperatures, closer to the solidification point, with better performance observed at intermediate infiltration pressures rather than at higher pressures. Under optimal conditions, over 10 million parallel Ga nanowires per square millimeter were produced, with an average diameter of 151 + 36 nm and a high aspect ratio of around 500.