  Developing single atom catalysts (SACs) for chemical reactions of vital
importance in renewable energy sector has emerged as a need of the hour. In
this perspective, transition metal based SACs with monolayer phosphorous
(phosphorene) as the supporting material are scrutinized for their
electrocatalytic activity towards oxygen reduction reaction (ORR), oxygen
evolution reaction (OER) and hydrogen evolution reaction (HER) from first
principle calculations. The detailed screening study has confirmed a breaking
of scaling relationship between ORR/OER intermediates resulting in varied
activity trends across the transition metal series. Group 9 and 10 transition
metal based SACs are identified as potential catalyst candidates with platinum
single atom offering bifunctional activity for OER and HER with diminished
overpotentials. Ambient condition stability analysis of SACs confirmed a
different extent of interaction towards oxygen and water compared to pristine
phosphorene suggesting room for improving the stability of phosphorene via
chemical functionalization.
