Dysprosium doped copper oxide (Cu1-xDyxO) nanoparticles enabled bifunctional electrode for overall water splitting

Abstract

Abstract The production of hydrogen, a favourable alternative to an unsustainable fossil fuel remains as a significant hurdle with the pertaining challenge in the design of proficient, highly productive and sustainable electrocatalyst for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Herein, the dysprosium (Dy) doped copper oxide (Cu1-xDyxO) nanoparticles were synthesized via solution combustion technique and utilized as a non-noble metal based bi-functional electrocatalyst for overall water splitting. Due to the improved surface to volume ratio and conductivity, the optimized Cu1-xDyxO (x\xa0=\xa00.01, 0.02) electrocatalysts exhibited impressive HER and OER performance respectively in 1\xa0M KOH delivering a current density of 10\xa0mAcm−2 at a potential of −0.18\xa0V vs RHE for HER and 1.53\xa0V vs RHE for OER. Moreover, the Dy doped CuO electrocatalyst used as a bi-functional catalyst for overall water splitting achieved a potential of 1.56\xa0V at a current density 10\xa0mAcm−2 and relatively high current density of 66\xa0mAcm−2 at a peak potential of 2\xa0V. A long term stability of 24\xa0h was achieved for a cell voltage of 2.2\xa0V at a constant current density of 30\xa0mAcm−2 with only 10% of the initial current loss. This showcases the accumulative opportunity of dysprosium as a dopant in CuO nanoparticles for fabricating a highly effective and low-cost bi-functional electrocatalyst for overall water splitting.