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Wang, Jianbo

Publications and source records attributed to Wang, Jianbo.

A reversible four-electron Sn metal aqueous battery

Sn is a promising metal anode for aqueous batteries, with up to four-electron redox available per atom (903 mAh g −1 Sn ). However, practically harnessing the four-electron Sn(OH) 6 2− /Sn reversibility remains challenging due to limited mechanistic understanding. Here, in this study, we reveal a kinetically asymmetric redox pathway involving a successive four-electron plating and a stepwise 2 + 2 electron stripping through a Sn(OH) 3 − intermediate. The crossover of Sn(OH) 3 − induces a reversible self-discharge that reduces Coulombic efficiency but does not impact cyclability, demonstrated by four-electron Sn-Ni full cells that sustain >800 h of stable cycling. By tuning the ion selectivity of the separator to suppress Sn(OH) 3 − crossover while allowing OH − transport, we further demonstrate high Sn utilization (67%) and high energy density (143.1 Wh L −1 cell). The results provide key understandings of the tradeoffs in engineering reversible multi-electron metal anodes and define a new benchmark for practical energy density that exceeds any Sn-based aqueous batteries to date.

SN anode↗

Direct Imaging of Resonant Phonon-Magnon Coupling

Detection of phonons is critical for research on the interconversion between resonantly coupled magnons and phonons. Here we report the direct visualization of the resonant coupling of magnons and phonons by microfocused Brillouin light scattering on the Ni/Li Nb O 3 hybrid heterostructure. The static patterns of surface acoustic wave phonons, originating from the interference between the incident wave ψ 0 (A 0 , k, φ 0 ) and reflected wave ψ 1 (A 1 , - k, φ 1 ), can be modulated by magnetic field due to the magnon-phonon coupling. By analyzing the information of phonons obtained from Brillouin spectroscopy, the properties of the magnon system (Ni film), e.g., ferromagnetic resonance field and resonance linewidth, can be determined. The results provide spatially resolved information about phonon manipulation and detection in a coupled magnon-phonon system.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Ultrathin high- κ antimony oxide single crystals

Ultrathin oxides have been reported to possess excellent properties in electronic, magnetic, optical, and catalytic fields. However, the current and primary approaches toward the preparation of ultrathin oxides are only applicable to amorphous or polycrystalline oxide nanosheets or films. Here, we successfully synthesize high-quality ultrathin antimony oxide single crystals via a substrate-buffer-controlled chemical vapor deposition strategy. The as-obtained ultrathin antimony oxide single crystals exhibit high dielectric constant (~100) and large breakdown voltage (~5.7 GVm -1 ). Such a strategy can also be utilized to fabricate other ultrathin oxides, opening up an avenue in broadening the applicaitons of ultrathin oxides in many emerging fields.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Phonon Transport Controlled by Ferromagnetic Resonance

The resonant coupling of phonons and magnons is important for the interconversion of phononic and spin degrees of freedom. We study the phonon transmission in LiNbO 3 manipulated by the dynamic magnetization in a Ni thin film. It is observed that the phonons can be absorbed strongly through resonant magnon-phonon coupling, which is realized by our modifying the magnon-phonon coupling within the Ni itself as well as our optimizing the interfacial coupling between Ni and LiNbO 3 . The line shapes of phonon transmission are further investigated considering the magnon-phonon interconversion in the elastically driven ferromagnetic resonance process. The results promote unique routes for phonon manipulation and detection in the presence of magnetization dynamics.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗