Caesium

Caesium (Cs) — 10-Year Trends

As of 2026-09-25 · the last 10 years

Research intensity on caesium has climbed steadily over the last decade, reaching about 59% of the element's all-time peak, a level that has not been seen since the mid-1960s.

Research intensity ran from about 43% of the element's own all-time peak in 2016 to about 59% in 2026 — a steady climb, and the all-time peak (1966) lies before this window. Over the same span its share of research attention across all elements rose. Among the 118 elements, caesium has a mid-sized research literature.

The number of papers involving the element rose from about 2,203 in 2016 to about 4,980 in 2025 (2.26x). That matches the growth of the literature as a whole over the same years: the general tide of scientific output, not a surge specific to the element.

The dominant area of research is All-Inorganic Perovskite Solar Cells and Thin Films, which accounts for about 69% of the element's recent research. This community focuses on the synthesis and interface engineering of all-inorganic cesium lead bromide perovskites for photovoltaic applications, with distinctive work on CsPbBr3 perovskite and cesium lead nanocrystals. Caesium is a minor presence in this much larger community, appearing in about 8% of its papers. The community's share of caesium research has remained steady over the window. Key work includes a 2025 paper in Nature Nanotechnology on homogeneous 2D/3D heterostructured tin halide perovskite photovoltaics, cited over 140 times, and a 2019 Science paper on efficient, stable solar cells using the inherent bandgap of α-phase formamidinium lead iodide, cited over 1,200 times.

A second significant community is Caesium Transport in Fukushima Soil Erosion, representing about 6.5% of recent research. These papers track caesium redistribution via soil erosion and loss in the Upper Oka basin following the Daiichi nuclear accident, with distinctive focus on radioactive caesium and soil loss. Caesium is a minor presence here, involved in about 3% of the community's papers. The share of this community has been steady. Notable work includes a 2023 Journal of Hazardous Materials paper on chitosan-minerals-based composites for adsorption of caesium, cobalt and europium, cited about 59 times, and a 2024 Water Environment Research review on radioactive elements in wastewater and potable water, cited about 26 times.

The third material community is Caesium Fountain Clocks and Primary Frequency Standards, holding about 2.1% of recent research. This group focuses on caesium atomic fountains and primary frequency standards, distinguishing them from broader optical lattice research. Caesium is a minor presence, involved in about 1% of the community's papers. The share has been steady. A 2024 Nature Physics paper on a dual-species Rydberg array, cited about 84 times, and a 2021 Physical Review Letters paper on improved limits for violations of local position invariance from atomic clock comparisons, cited over 200 times, anchor this field.

Overall, the composition of caesium research has remained remarkably stable over the last decade. The perovskite solar cell community continues to dominate, while the nuclear waste and atomic clock communities maintain their smaller but consistent shares. Other research communities, which together hold about 23% of the element's recent work, have also remained steady.

For a deeper look at the current state of caesium research, see the element's Last 12 Months and Executive Brief reports.