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Nb substitution via hydrothermal synthesis led to a new β′-LiVOPO4 phase with complex defect chemistries. The samples showed improved high-voltage rate capabilities and an enlarged voltage hysteresis due to a partial V4+/V3+ redox reaction.

BackgroundAutism spectrum disorder (ASD) is a neurodevelopmental disorder with a growing prevalence of sleep problems associated with significant behavioral problems and more severe autism clinical presentation. Little is known about the relationships between autism traits and sleep problems in Hong Kong. Therefore, this study aimed to examine whether children with autism have increased sleep problems than non-autistic children in Hong Kong. The secondary objective was to examine the factors associated with sleep problems in an autism clinical sample.MethodsThis cross-sectional study recruited 135 children with autism and 102 with the same age range of non-autistic children, aged between 6 and 12 years. Both groups were screened and compared on their sleep behaviors using the Children's Sleep Habits Questionnaire (CSHQ).ResultsChildren with autism had significantly more sleep problems than non-autistic children [t(226.73) = 6.20, p < 0.001]. Bed -sharing [beta = 0.25, t(165) = 2.75, p = 0.07] and maternal age at birth [beta = 0.15, t(165) = 2.05, p = 0.043] were significant factors associated with CSHQ score on the top of autism traits. Stepwise linear regression modeling identified that only separation anxiety disorder (beta = 4.83, t = 2.40, p = 0.019) best-predicted CSHQ.ConclusionIn summary, autistic children suffered from significantly more sleep problems and co-occurring separation anxiety disorder brings greater sleep problems as compared to non-autistic children. Clinicians should be more aware of sleep problems to provide more effective treatments to children with autism.

Introduction. Public health students are not systematically trained how positionality and power impact public health practice. A grounding in anti-oppression equips practitioners with tools to recognize the impact of present and historical contexts, foster critical self-reflection, and address systems of oppression. The goal of this study was to gather evidence of how anti-oppression is incorporated in public health teaching. Method. Purposive sampling was used to identify public health faculty who engage in anti-oppressive practice across accredited schools of public health espousing an explicit commitment to social justice. Semistructured in-depth interviews were conducted between January and April 2020 via Zoom; analyses were informed by constructivist grounded theory. Results. Twenty-six faculty from eight schools of public health and one school of medicine participated. Participants highlighted challenges in and techniques on how to engage in anti-oppressive teaching. Three overarching methods for incorporating anti-oppressive principles in pedagogy were identified: facilitating critical consciousness, creating equitable and mindful classrooms, and discussing historical context and systems of oppression, alongside discussing challenges associated with using an anti-oppressive lens in teaching. Conclusions. Anti-oppression is an explicit framework that can be incorporated in training future public health practitioners to work toward dismantling systems of oppression through addressing issues of power and privilege. Findings from this study indicate that faculty are interested in and engage in anti-oppressive teaching but lack consistent training and institutional support. This study offers tools that faculty can employ in the classroom toward practicing anti-oppressive public health pedagogy.

Lithium vanadyl phosphate (LiVOPO4) is an attractive cathode material for next-generation lithium-ion batteries, having the ability to reversibly intercalate two Li ions per transition-metal redox ...

e-LiVOPO4 has been synthesized through the hydrothermal method by adjusting the pH of the hydrothermal solution and the reaction temperature. This phase is formed between 180 and 220 °C, as diamond...

Lithium-ion batteries now dominate electrochemical energy storage for vehicle propulsion and grid storage in addition to portable electronics. In 2022, they celebrate their 50th anniversary, and yet still achieve only 25% of their theoretical energy density. The dominant anode and cathode today are graphitic carbon and the layered NMC oxides, LI[NiMnCoAl]O2. Both need improving. Most of the carbon in the anode must go, and the NMCs need pushing to their limit and at the same time eliminating cobalt. I will today discuss the challenges faced as we push the limits of the NMCs to their limits, > 80% lithium cycling, and Ni>0.8 and Co

Li-ion intercalation compound enlisting multi-electron redox is a promising strategy to maximize the storage capacity of LIBs. Lithium vanadyl phosphate, LiVOPO4, is one such material that can intercalate up to two Li+ ions per vanadium ion through the change in vanadium valence from V5+ to V3+, which translates to a theoretical capacity of 305 mAh/g and an energy density above 900 Wh/kg. However, Li-ion intercalation in the high voltage region (V5+/V4+) is kinetically limited by the sluggish Li-ion diffusion, and thus impedes the use of LiVOPO4 in practical applications. The goal of this work is to explore experimentally if niobium substitution can enhance the electrochemical performance of LiVOPO4. Lab X-ray diffraction, electron microscopy-energy-dispersive X-ray analysis, and inductively coupled plasma atomic emission spectroscopy indicate niobium is substituted into the LiVOPO4 crystal structure. A qualitative difference in the charge-discharge voltage profile is observed between the pristine and the niobium-substituted samples, suggesting a more complex substitution mechanism than the direct V substitution with Nb. The effects of niobium substitution on the crystal structure and the electrochemical performance of LiVOPO4 will be discussed.

Lithium vanadyl phosphate (LiVOPO4) is an attractive cathode material for next-generation lithium ion batteries, having the ability to reversibly extract and insert two lithium ions to reach a theoretical capacity of 318 mAh/g. LiVOPO4 also has very high energy density over two voltage plateaus of about 2.5 and 4 V. However, the transition between the two voltage plateaus goes differently upon lithiation and delithiation, causing poor energy efficiency and cycling stability. Here we explore experimentally and by the first-principle calculations, if there is room to improve the efficiency and cyclability of this material with the use of chromium substitution. A series of lithium vanadyl phosphates with varying percentages of chromium from two different chromium sources, chromium oxide and chromium acetate, are synthesized by hydrothermal method. The structure and composition of the products are determined by x-ray diffraction and inductively coupled plasma atomic emission spectroscopy. The effect of chromium substitution on the reaction voltages is compared to the first-principle calculation results and the electrochemical performance as a function of chromium substitution is discussed. This research is supported as part of the NorthEast Center for Chemical Energy Storage (NECCES), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0012583

Maintaining the structural reversibility of multiple electron transfer cathodes is a challenge one has to address in order to increase the energy density of current lithium-ion batteries. ε-VOPO4 is a promising cathode material with two redox transitions of V3+/V4+ and V4+/V5+ at about 2.5 and 4 V, respectively. However, the reversibility and cycling stability is compromised with more than one lithium cycling. The goal of this work is to investigate if the substitution of molybdenum can enhance the electrochemical performance of ε-VOPO4. We have focused on molybdenum because it is predicted by the first-principle calculations to display multiple redox potentials in useful voltage window and to form relatively stable substituted ε-VOPO4 phases. We have refined the synthesis method, where by changing a solvent we can control morphology and obtain either loose uniform 100 nm particles, or make those particles form secondary micron-sized spheres. Combing the analysis of X-ray diffraction, and inductively coupled plasma mass spectrometry, we have determined the limits of molybdenum substitution in the structure. The effects of the substitution and morphology on the electrochemical performance will be discussed. This research is supported as part of the NorthEast Center for Chemical Energy Storage (NECCES), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0012583. CS gratefully acknowledges the financial support from Graduate Assistance in Areas of National Need (GAANN) Fellowship and Binghamton University Provost's Doctoral Summer Fellowship.