Ultrahigh energy storage density of 52.4 J cm with optimistic efficiency of 72.3% is achieved by interface engineering of epitaxial lead-free oxide multilayers at room temperature. Moreover, the excellent thermal stability of the performances provides solid basis for widespread applications of the thin film systems in modern electronic and power modules in harsh working environments.

Aqueous rechargeable zinc‐based batteries have sparked a lot of enthusiasm in the energy storage field recently due to their inherent safety, low cost, and environmental friendliness. Although remarkable progress has been made in the exploration of performance so far, there are still many challenges such as low working voltage and dissolution of electrode materials at the material and system level. Herein, the central tenet is to establish a systematic summary for the construction and mechanism of different aqueous zinc‐based batteries. Details for three major zinc‐based battery systems, including alkaline rechargeable Zn‐based batteries (ARZBs), aqueous Zn ion batteries (AZIBs), and dual‐ion hybrid Zn batteries (DHZBs) are given. First, the electrode materials and energy storage mechanism of the three types of zinc‐based batteries are discussed to provide universal guidance for these batteries. Then, the electrode behavior of zinc anodes and strategies to deal with problems such as dendrite and passivation are recommended. Finally, some challenge‐oriented solutions are provided to facilitate the next development of zinc‐based batteries. Combining the characteristics of zinc‐based batteries with good use of concepts and ideas from other disciplines will surely pave the way for its commercialization.

Fundamental understanding of constructing elevated catalysts to realize fast electron transfer and rapid mass transport in oxygen reduction reaction (ORR) chemistry by interface regulation and structure design is important but still ambiguous. Herein, a novel jellyfish-like Mott-Schottkytype electrocatalyst is developed to realize fast electron transfer and decipher the structure-mass transport connection during ORR process. Both spectroscopy techniques and density functional theory calculation demonstrate electrons spontaneously transfer from Fe to N-doped graphited carbon at the heterojunction interface, thus accelerating electron transfer from electrode to reactant. Dynamic analysis indicates unique structure can significantly improve mass transport of oxygen-species due to two factors: one is electrolyte streaming effect caused by tentacle-like carbon nanotubes; the other is effective collision probability in the semiclosed cavity. Therefore, this Mott-Schottky-type catalyst delievers superior ORR performance with high onset potential, positive half wave potential, and large current density. It also exhibits low overpotential when serving as an air cathode in Zn-air batteries. This work deepens understanding of the two key factors-electron transfer and mass transport-on determining the kinetic reaction of ORR process and offers a new avenue in constructing efficient Mott-Schottky electrocatalysts.

and Technology. His research direction is electronic functional materials, including designing and exploiting piezoelectrics, ferroelectrics, and pyroelectrics. Ge Wang is currently working as a PDRA in functional materials and devices group at the University of Sheffield, UK. He obtained his Ph.D. from the University of Manchester in 2017 then moved to the University of Sheffield. His research interests include dielectric ceramic capacitors, piezoelectrics, solid oxide fuel cells, and Li batteries.

Molecular dynamics simulations are conducted to investigate homogeneous nucleation and growth of melt in copper described by an embedded-atom method (EAM) potential. The accuracy of this EAM potential for melting is validated by the equilibrium melting point obtained with the solid-liquid coexistence method and the superheating-supercooling hysteresis method. We characterize the atomistic melting process by following the temperature and time evolution of liquid atoms. The nucleation behavior at the extreme superheating is analyzed with the mean-first-passage-time (MFPT) method, which yields the critical size, steady-state nucleation rate, and the Zeldovich factor. The value of the steady-state nucleation rate obtained from the MFPT method is consistent with the result from direct simulations. The size distribution of subcritical nuclei appears to follow a power law similar to three-dimensional percolation. The diffuse solid-liquid interface has a sigmoidal profile with a 10%-90% width of about 12 A near the critical nucleation. The critical size obtained from our simulations is in reasonable agreement with the prediction of classical nucleation theory if the finite interface width is considered. The growth of melt is coupled with nucleation and can be described qualitatively with the Johnson-Meh-Avrami law. System sizes of 10(3)-10(6) atoms are explored, and negligible size dependence is found for bulk properties and for the critical nucleation.

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A large energy storage density (ESD) of 30.4 J/cm and high energy efficiency of 81.7% under an electrical field of 3 MV/cm was achieved at room temperature by the fabrication of environmentally friendly lead-free BaZrTiO epitaxial thin films on Nb-doped SrTiO (001) substrates by using a radio-frequency magnetron sputtering system. Moreover, the BZT film capacitors exhibit great thermal stability of the ESD from 16.8 J/cm to 14.0 J/cm with efficiency of beyond 67.4% and high fatigue endurance (up to 10 cycles) in a wide temperature range from room temperature to 125 °C. Compared to other BaTiO-based energy storage capacitor materials and even Pb-based systems, BaZrTiO thin film capacitors show either high ESD or great energy efficiency. All of these excellent results revealed that the BaZrTiO film capacitors have huge potential in the application of modern electronics, such as locomotive and pulse power, in harsh working environments.

BCT/BZT multilayer with excellent energy storage performances with optimistic thermal stability has been fabricated using RF-sputtering system. Not only huge energy storage density of 51.8 J cm−3 with great efficiency of 81.2% at room temperature has been obtained, but also an optimistic thermal stability from RT to 200 °C has been investigated.