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1. Mo-substitution in V₂O₅ tunes the structure towards three-dimensional connectivity and improves Li-ion battery cycling

   https://doi.org/10.1088/2515-7639/adc83e  

   Parui, Kausturi; Gardner, Bonnie G; Pitton, Kathryn A; Caracuel, Noah G; Vidal-Torres, Emily; Gandhi, Shornam; Guiton, Beth S; Nino, Juan C; Butala, Megan M (April 2025, Journal of Physics: Materials)

   Abstract The development of alternative energy sources is crucial for reducing reliance on fossil fuels, particularly for mobile applications such as personal electronics and transportation. This necessitates the advancement of battery materials based on abundant and inexpensive constituent elements. To achieve this requires investigating materials in a broader compositional and structural design space. Early transition metal oxides, including the intercalation electrode $\alpha -$V₂O₅, however, the performance of V₂O₅ is hindered by phase transformations during battery cycling that lead to capacity fade and short device lifetimes. This study investigates the modification of V₂O₅through Mo substitution in a series of the form V ${}_{2-x}$Mo_xO₅ for x= 0.05, 0.1, 0.2, 0.4, 0.6, and 0.8. X-ray diffraction data reveal progressive structural changes with increasing Mo content, which in turn change the progression of phase transformations during the first discharge. The different product also results in different cycling profile shapes that indicate differences in the charge storage mechanism as a function of Mo content. As a result, samples with higher Mo-substitution, especially V_1.2Mo_0.8O₅, have narrower hysteresis, higher capacity, and improved capacity retention. While there is a limited solubility of Mo in the V₂O₅ structure, with secondary phases and defects at many compositions, we show that Mo substitution alters the cycling behavior of V₂O₅ to deep discharge, which can inform the design of intercalation materials for energy storage applications. 

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2. Precision measurement of lifetime and branching ratios of the $4f^{13}5d6s^1{[5/2]}_{5/2}$ state in ${\mathrm{Yb}}^{+}$ ions

   https://doi.org/10.1103/mwwc-kng1  

   Duraisamy_Suganthi, Midhuna; So, Visal; Menon, Abhishek; Tomaras, George; Zhuravel, Roman; Pagano, Guido (December 2025, Physical Review Research)

   We report spectroscopic and time-resolved experimental observations to characterize the $\left[\mathrm{Xe}\right]4f^{13}\left({}^{2}F_{5/2}^o\right)5d6s\left({}^{1}D\right){}^1{[5/2]}_{5/2}^o$state in ${}^{172}\mathrm{Yb}^{+}$ ions. We access this state from the metastable $4f^{14}5d\left({}^{2}D_{3/2,5/2}\right)$manifold and observe an unexpectedly long lifetime of $\tau =37.9\left(9\right)\mu \mathrm{s}$ that allows visible Rabi oscillations and resolved-sideband spectroscopy. Using a combination of coherent population dynamics, high-fidelity detection and heralded state preparation, and optical pumping methods, we measure the branching ratios to the ${}^{2}D_{3/2}, {}^{2}D_{5/2}$, and ${}^{2}S_{1/2}$states to be $0.359\left(2\right)$, 0.639(2), and $0.0023\left(16\right)$, respectively. The branching ratio to the $4f^{13}6s^2\left({{}^{2}F}_{7/2}\right)$is compatible with zero within our experimental resolution. We also report measurements of Landé $g$-factor of the ${}^1{[5/2]}_{5/2}^o$state. Further, the branching ratio of the ${}^{2}D_{5/2}$to ${}^{2}S_{1/2}$decay in ${}^{172}\mathrm{Yb}^{+}$ was measured to be 0.188(3), improving its relative uncertainty by an order of magnitude. Our measurements provide experimental benchmarks for better understanding the atomic structure of ${\mathrm{Yb}}^{+}$ ions, which still lacks accurate numerical descriptions, and the use of high-lying excited states for partial detection and qubit manipulation in the architecture. 

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3. Environmentally responsible synthesis of high-performance P2-Na _2/3 [Ni _1/3 Mn _2/3 ]O ₂ sodium-ion battery cathodes

   https://doi.org/10.1039/d4ta03708a  

   Fu, Jintao; Hassan, Mohamed H; Liu, Jiaxin; Koh, Hyeongjun; Ng, Alexander K; Bruzzi, Chiara; Corsi, John S; Detsi, Eric (January 2024, Journal of Materials Chemistry A)

   An environmentally responsible synthesis of Na_2/3[Ni_1/3Mn_2/3]O₂(NNMO) enabled by direct conversion of metallic Ni powder, releasing only O₂and H₂O as byproducts. The resulting NNMO exhibits excellent cycling performance as a Na-ion battery cathode. 

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4. Is surface modification effective to stabilize high-voltage cycling for layered P2-Na _2/3 Ni _1/3 Mn _2/3 O ₂ cathodes?

   https://doi.org/10.1039/D4CC02819H  

   Niu, Fangzhou; Qiao, Linna; Huang, Heran; Odero, Elninoh A; Zhou, Guangwen; Liu, Hao (October 2024, Chemical Communications)

   Surface coating of Na_2/3Ni_1/2Mn_2/3O₂particles suppresses high-voltage polarization but not capacity fade, which is dominated by bulk structure degradation. 

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5. Visualizing the alignment of lone pair electrons in La ₃ AsS ₅ Br ₂ and La ₅ As ₂ S ₉ Cl ₃ to form an acentric or centrosymmetric structure

   https://doi.org/10.1039/D3CE00834G  

   Cicirello, Andrea; Swindle, Andrew; Wang, Jian (November 2023, CrystEngComm)

   Heteroanionic chalcohalides La₃AsS₅Br₂and La₅As₂S₉Cl₃exhibit a good example of how alignment of lone pair electrons affects the formation of acentric crystal structure. 

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