Iridium (Ir) catalysts are essential for the acidic oxygen evolution reaction (OER) in proton-exchange membrane water electrolyzers (PEMWEs), but their high cost, scarcity, and geographical ...

Polymer microneedles (MNs) attract considerable attention due to their sound biocompatibility and low manufacturing cost. In this study, we prepared polypropylene (PP) MNs utilizing ultrasonic ...