Biswas Souvick, Cokas Jack, Gee Winston, Paul Dababrata, Dias Nureshan, Morgan Harry W T, Finn Matthew T, Hudak Bethany M, Godbold Perrin M, Klug Christopher A, Epshteyn Albert, Alexandrova Anastassia N, Ahmed Musahid, Kaiser Ralf I
Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii, USA.
Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA.
Nat Commun. 2025 Jul 23;16(1):6793. doi: 10.1038/s41467-025-62112-2.
Sonochemically-synthesized atomically-dispersed titanium-aluminum-boron nanopowder (TiAlB NP) exhibits a remarkable low-temperature catalytic activation of aliphatic C-H bonds at 750 K followed by C-C bond activation thus emerging as a potent low-cost alternative to expensive platinum group metals. Here, the model saturated hydrocarbon, exo-tetrahydrodicyclopentadiene (CH), undergoes catalytic decomposition on TiAlB NPs in a chemical microreactor to produce 1,3-cyclopentadiene (c-CH), cyclopentene (c-CH), and molecular hydrogen (H) as detected in situ via isomer-selective, single-photon ionization time-of-flight mass spectrometry. Extensive electronic structure theory calculations on model clusters of the catalyst decode a unique synergy among the atomic constituents of the catalyst and chemical bonding in this stepwise, retro Diels Alder reaction: Ti, although insensitive to C-H activation in its metallic state, initiates the catalysis via chemisorption of the hydrocarbon, adjacent B centers readily abstract hydrogen atoms and store them during the catalytic cycle, while Al stabilizes the catalyst structure yet providing space for critical docking sites for the departing hydrocarbons.
声化学合成的原子分散钛铝硼纳米粉末（TiAlB NP）在750 K时对脂肪族C-H键表现出显著的低温催化活化作用，随后是C-C键活化，因此成为昂贵铂族金属的一种有效的低成本替代品。在此，模型饱和烃外向四氢二环戊二烯（CH）在化学微反应器中于TiAlB NPs上进行催化分解，生成1,3-环戊二烯（c-CH）、环戊烯（c-CH）和分子氢（H），通过异构体选择性单光子电离飞行时间质谱原位检测到这些产物。对催化剂模型簇进行的广泛电子结构理论计算揭示了催化剂原子成分之间独特的协同作用以及该逐步逆狄尔斯-阿尔德反应中的化学键合：Ti虽然在金属态下对C-H活化不敏感，但通过烃的化学吸附引发催化作用，相邻的B中心很容易提取氢原子并在催化循环中储存它们，而Al稳定催化剂结构，同时为离去的烃提供关键对接位点的空间。
