Analysis of the literature from 2011-2021 reveals that of the three areas in GHE research, green hydrogen production had the largest upward momentum throughout the decade in terms of total publication volume, whereas hydrogen storage and hydrogen fuel cells experienced a dip in publication followed by an increase in the second half of the decade largely fueled by increasing patent activity. These increasing patent volumes suggest that hydrogen storage and fuel cells are more technologically mature than green hydrogen production, whose proportion of patents has yet to reach 20%. Throughout the decade, the diversity of catalytic materials used in green hydrogen production experiments expanded, while hydrogen storage and fuel cells narrowed in the scope of materials used as a whole. When combined with the increases in patent volume, it appears that these two fields have been focusing in on potentially commercially viable materials, whereas green hydrogen production is still at an exploratory stage where many different avenues are being explored.