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Current synthetic pathways for uranyl peroxide materials introduce high initial concentrations of aqueous H₂O₂that decline over time. Alternatively, in situ generation of organic peroxide would maintain constant concentrations of peroxide over prolonged periods of time and open new pathways to novel uranyl peroxide compounds. Herein, we demonstrate this concept through the synthesis of a nanotube‐like uranyl peroxide phosphate (NUPP), Na₁₂[(UO₂)(μ‐O₂)(HPO₄)]₆(H₂O)₄₀, making use of the inhibited autoxidation of benzaldehyde in benzyl alcohol solutions in the presence of phosphonate ligands. The unique feature ofNUPPis the bent dihedral angle U‐(μ‐O₂)‐U (123.9°±0.4° to 124.6°±0.5°), which allows hexameric uranyl peroxide macrocycles to adopt the nanotubular topology and prevents the formation of nanocapsules. Raman spectroscopy of the solution phase confirms our mechanistic understanding of the reaction pathway and confirms that consistent levels of peroxide are generated in situ over an extended period of time.

Current synthetic pathways for uranyl peroxide materials introduce high initial concentrations of aqueous H₂O₂that decline over time. Alternatively, in situ generation of organic peroxide would maintain constant concentrations of peroxide over prolonged periods of time and open new pathways to novel uranyl peroxide compounds. Herein, we demonstrate this concept through the synthesis of a nanotube‐like uranyl peroxide phosphate (NUPP), Na₁₂[(UO₂)(μ‐O₂)(HPO₄)]₆(H₂O)₄₀, making use of the inhibited autoxidation of benzaldehyde in benzyl alcohol solutions in the presence of phosphonate ligands. The unique feature ofNUPPis the bent dihedral angle U‐(μ‐O₂)‐U (123.9°±0.4° to 124.6°±0.5°), which allows hexameric uranyl peroxide macrocycles to adopt the nanotubular topology and prevents the formation of nanocapsules. Raman spectroscopy of the solution phase confirms our mechanistic understanding of the reaction pathway and confirms that consistent levels of peroxide are generated in situ over an extended period of time.

Keggin‐type polyaluminum cations belong to a unique class of compounds with their large positive charge, hydroxo bridges, and divergent isomerization/oligomerization. Previous reports indicated that oligomerization of this species can only occur through one isomer (δ), but herein we report the isolation of largest Keggin‐type cluster that occurs through self‐condensation of four ϵ‐isomers ϵ‐GeAl₁₂⁸⁺to form [Ge₄O₁₆Al₄₈(OH)₁₀₈(H₂O)₂₄]²⁰⁺cluster (Ge₄Al₄₈). The cluster was crystallized and structurally characterized by single‐crystal X‐ray diffraction (SCXRD) and the elemental composition was confirmed by ICP‐MS and SEM‐EDS. Additional dynamic light scattering experiments confirms the presence of theGe₄Al₄₈in thermally aged solutions. DFT calculations reveal that a single atom Ge substitution in tetrahedral site of ϵ‐isomer is the key for the formation ofGe₄Al₄₈because it activates deprotonation at key surface sites that control the self‐condensation process.

Keggin‐type polyaluminum cations belong to a unique class of compounds with their large positive charge, hydroxo bridges, and divergent isomerization/oligomerization. Previous reports indicated that oligomerization of this species can only occur through one isomer (δ), but herein we report the isolation of largest Keggin‐type cluster that occurs through self‐condensation of four ϵ‐isomers ϵ‐GeAl₁₂⁸⁺to form [Ge₄O₁₆Al₄₈(OH)₁₀₈(H₂O)₂₄]²⁰⁺cluster (Ge₄Al₄₈). The cluster was crystallized and structurally characterized by single‐crystal X‐ray diffraction (SCXRD) and the elemental composition was confirmed by ICP‐MS and SEM‐EDS. Additional dynamic light scattering experiments confirms the presence of theGe₄Al₄₈in thermally aged solutions. DFT calculations reveal that a single atom Ge substitution in tetrahedral site of ϵ‐isomer is the key for the formation ofGe₄Al₄₈because it activates deprotonation at key surface sites that control the self‐condensation process.