As of 15 August 2026 · the last 10 years
Hydrogen's research intensity today sits at roughly 84% of its all-time peak, a peak reached back in 1980 — well outside this ten-year window.
The shape of the last decade is a shallow dip and a slow, steady recovery. From 2016 through 2021, the element's research intensity drifted gently downward, falling from about 208,000 to just over 202,000 in the underlying volume measure, with the ratio to its own historical peak easing from 0.85 to 0.82. Publication counts told a milder version of the same story, climbing modestly from roughly 1,100 to 1,500 papers a year. Then, starting in 2022, the trajectory turned: intensity crept back up through 2023 and 2024, and by 2025 it had recovered to about 210,000 — a 0.85 ratio to the 1980 peak, the highest point in the window. Publication counts accelerated more sharply, jumping from 1,873 in 2022 to 2,846 in 2024 and 4,936 in 2025. The 2026 figure (756 so far) reflects only the first eight months of the year.
What has the research actually been about? The highest-impact papers in the window cluster around a clear set of themes: hydrogen's role in the broader energy transition, the practical challenges of producing and storing it, and the electrochemistry that underpins green hydrogen generation. A 2025 review in the International Journal of Hydrogen Energy surveys the full production–storage–transportation pipeline; a Nature Energy piece the same year confronts the "green hydrogen ambition and implementation gap"; and a Science paper explores hydrogenation of CO₂ as a route to sustainable fuels. On the electrocatalysis side, work on bifunctional water-splitting catalysts (Chemical Reviews, 2024) and ultrastable oxygen-evolution materials (Science, 2025) anchors the fundamental-science track, while a 2023 Nature result pushing solar-to-hydrogen conversion past 9% marks a concrete efficiency milestone.
The application mix shifted noticeably across the window. In the first half ('17–'21), the hydrogen evolution reaction — the core electrochemical step of splitting water — accounted for roughly 32% of the element's application footprint. By the second half ('22–'26), that share had fallen to about 14%, while "green hydrogen" as a named application surged from roughly 2% to nearly 13%. Ammonia, already the dominant application at about 37%, grew to 42%, and hydrogen storage edged up from 18% to 20%. The net effect: the conversation moved from the fundamental electrochemistry of making hydrogen to the systems-level question of where and how to deploy it.
For a fuller picture of where hydrogen research stands right now, the Last 12 Months and Executive Brief reports for this element are worth a look.
What changed in the past year: new papers, shifting applications, emerging collaborators. See the momentum over a shorter window than the decade view.
Personal →See recent trends — Personal.
A by-topic status read of what changed and what's new — built for decision-makers, not search engines. Citation clusters, emerging applications, and the papers that matter most.
Professional →See the executive read — Professional.
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Showing Hydrogen's three strongest connections. Personal opens the slider and the whole 118-element graph.