Researchers at East China Normal University and Peking University have demonstrated ultrafast bimolecular reaction catalysis inside helium nanodroplets, according to a paper published in Nature Communications. The experimental team trapped H2-H2 and D2-D2 dimers inside a quantum-phase droplet host at 0.37 Kelvin to observe bond formation dynamics using femtosecond pump-probe spectroscopy.
The low-temperature confinement altered reaction kinetics, accelerating bond formation through engineered nuclear quantum effects. The creation of H3+ occurred in 59 ± 10 femtoseconds within the nanodroplets, down from 152 ± 17 femtoseconds measured in the gas phase.
Isotope mass influenced the speed of the reaction catalysis. Heavier D2-D2 dimers forming D3+ showed a smaller reduction in reaction duration, dropping from 153 ± 8 femtoseconds in the gas phase to 111 ± 9 femtoseconds in the host droplet. Molecular dynamics simulations conducted alongside the experiments indicated that lighter hydrogen isotopes undergo higher quantum delocalization under cryogenic confinement, driving faster reaction rates.
The experimental research involved primary contributions from lead authors Jiaxuan Chen, Leshi Zhao, and Hao Huang, alongside researchers from institutions in China and Spain. Participating organizations included the Universidad Autónoma de Madrid, CSIC in Madrid, Shanxi University, Wuhan Institute of Technology, Huazhong University of Science and Technology, and the Chongqing Institute of East China Normal University. Funding for the project included support from the Quantum Science and Technology-National Science and Technology Major Project and the National Natural Science Foundation of China. The paper was submitted on November 28, 2025, accepted on July 17, 2026, and published on July 30, 2026.
