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The dynamic photoluminescence properties, and potential quenching mechanisms, ofanti-B₁₈H₂₂, 4,4′-Br₂-anti-B₁₈H₂₀, and 4,4′-I₂-anti-B₁₈H₂₀are investigated in solution and polymer films.

 

Abstract This work describes select narratives pertaining to undergraduate teaching and mentorship at UCLA Chemistry and Biochemistry by Alex Spokoyny and his junior colleagues. Specifically, we discuss how individual undergraduate researchers contributed and jump-started multiple research themes since the conception of our research laboratory. This work also describes several recent innovations in the inorganic and general chemistry courses taught by Spokoyny at UCLA with a focus of nurturing appreciation for research and creative process in sciences including the use of social media platforms. 

Bromination of the luminescent borane, anti -B 18 H 22 , via electrophilic substitution using AlCl 3 and Br 2 , yields the monosubstituted derivative 4-Br- anti -B 18 H 21 as an air-stable crystalline solid. In contrast to the unsubstituted parent compound, 4-Br- anti -B 18 H 21 possesses dual emission upon excitation with UV light and exhibits fluorescence at 410 nm and phosphorescence at 503 nm, with Φ total = 0.07 in oxygen-free cyclohexane. Increased oxygen content in cyclohexane solution quenches the phosphorescence signal. The fluorescent signal intensity remains unaffected by oxygen, suggesting that this molecule could be used as a ratiometric oxygen probe. 

We report our discovery of utilizing perhydroxylated dodecaborate clusters ([B 12 (OH) 12 ] 2− ) as a molecular cross-linker to generate a hybrid tungsten oxide material. The reaction of [N n Bu 4 ] 2 [B 12 (OH) 12 ] with WCl 6 , followed by subsequent annealing of the product at 500 °C in air successfully produces a tungsten oxide material cross-linked with B 12 -based clusters. The comprehensive structural study of the produced hybrid material confirms a cross-linked network of intact boron-rich clusters and tungsten oxides. We further demonstrate how these robust B 12 -based clusters in the resulting hybrid tungsten oxide material can effectively preserve the specific capacitance up to 4000 cycles and reduce the charge transfer resistance as well as the response time compared to that of pristine tungsten oxide. Ultimately, this work highlights a promising capability of boron-rich clusters in hybrid metal oxides to obtain fast and stable supercapacitors with high capacitance.