Protactinium

Protactinium (Pa) — 10-Year Trends

As of 2026-09-25 · the last 10 years

Research intensity is currently about 10% of the element's all-time peak, a level that has held steady since the peak occurred in 1967, well before this window.

Research intensity ran from about 12% of the element's own all-time peak in 2016 to about 10% in 2026 — essentially flat across the window, and the all-time peak (1967) lies before this window. Over the same span its share of research attention across all elements fell. Among the 118 elements, protactinium has one of the smaller research literatures of any element.

The number of papers involving the element rose from about 77 in 2016 to about 107 in 2025 (1.39x). That is slower than the literature as a whole grew over the same years, so the element lost ground in the wider body of research even as its own count rose.

The most significant shift in the last decade is the consolidation of work around the fundamental electronic properties of the element. The community focused on Protactinium Mono-oxo Cation Stability and Electronic Structure now accounts for about 31% of the element's recent research, up from about 21% in the previous period. This is a rising area where protactinium is a minor presence in a much larger community of lanthanide and actinide coordination chemistry, with under 1% of those papers involving protactinium. The work investigates the stability and electronic properties of the protactinium mono-oxo cation using first-principle calculations. A key recent contribution is "Unlocking Novel δ and φ Bonding Modes in Actinides via Oxidation State Control" (2025), cited about 12 times, which explores these bonding modes.

The largest single community remains Stable Isotope Geochemistry of Sedimentary Basins and Marine Environments, holding about 22% of the element's recent research, a steady share compared to about 17% previously. Here, protactinium is a minor presence in a much larger community, with under 1% of its papers involving protactinium. The distinctive focus on geochemical tracers and ocean circulation models places protactinium within broader climate and geological studies. The most cited work in this area is "North Atlantic ocean circulation and abrupt climate change during the last glaciation" (2016), cited over 540 times, which utilizes such tracers.

The third material community, Nuclear Fuel, Coolant and Structural Materials for Advanced Reactor Systems, has seen a decline in share, dropping from about 25% to about 15% of the element's recent research. In this context, protactinium is a minor presence in a much larger community, with under 1% of its papers involving protactinium. The work involves pressurized water reactors and burnable poisons. A notable recent study is "Neutronic analysis of an EPR core employing PaO2 and NpO2 as burnable absorber coatings" (2026), not yet cited, which examines these applications.

Overall, the literature is consolidating around fundamental electronic structure and geochemical applications, while nuclear fuel applications lose relative share. For a deeper look at the current standing of this element, see the Last 12 Months or Executive Brief reports.