Interfacial creation of positively charged sites in LaPO₄/Fe₃(PO₄)₂ heterojunctions for high-current-density oxygen evolution

The creation of positively charged active sites is crucial for enhancing the adsorption of negatively charged hydroxide ions, thereby improving the sluggish oxygen evolution reaction (OER). We engineered LaPO4/Fe3(PO4)2 heterojunctions with a low flat-band potential, facilitating interfacial charge transfer and generation of positively charged holes, resulting in a highly active and stable OER catalyst at 500 mA cm-2.