Hybrid light/acoustic-powered microbowl motors, composed of gold (Au) and titanium dioxide (TiO 2 ) with a structure-dependent optical modulation of both their movement and collective behavior are reported by reversing the inner and outer positions of Au and TiO 2 . The microbowl propels in an acoustic field toward its exterior side. UV light activates the photochemical reaction on the TiO 2 surface in the presence of hydrogen peroxide and the Au/TiO 2 system moves toward its TiO 2 side by self-electrophoresis. Controlling the light intensity allows switching of the dominant propulsion mode and provides braking or reversal of motion direction when TiO 2 is on the interior, or accelerated motion when the TiO 2 is on its exterior. Theoretical simulations offer an understanding of the acoustic streaming flow and self-electrophoretic fluid flow induced by the asymmetric distribution of ions around the microbowl. The light-modulation behavior along with the tunable structure also leads to the control of the swarm behaviors under the acoustic field, including expansion or compaction of ensembles of microbowls with interior and exterior TiO 2 , respectively. Such structure-dependent motion control thus paves the way for a variety of complex microscale operations, ranging from cargo transport to drug delivery in biomedical and environmental applications.

Severe particle aggregation and performance fading hinder the application of Mn-based chalcogenides (MBCs) in sodium-ion batteries, and most modifications focus on complicated structure design. With the introduction of renewable Pleurotus eryngii, MBCs/honeycomb-like carbon (HLC) composites are prepared via a simple and sustainable method in this work. Benefitting from the complex and protogenetic carbon frameworks, the composites show much better sodium storage performance than pure chalcogenides. The outstanding performance of the composites can be attributed to the effective cooperation between high-capacity MBCs and high-stability HLC. Besides, real-time kinetics and rate-determining steps of the sodium storage process are also revealed by in situ electrochemical impedance spectrum analysis. This simple and sustainable method may be not only feasible for complicated-structure MBCs composites but also promising for other metal chalcogenides.

No abstract

No abstract

Polycrystalline γ-LiAlO2 pellets were sequentially irradiated with 120 keV He+ and 80 keV D2+ ions to the fluences of 1 × 1017 and 2 × 1017 (He+ + D+)/cm2 at 573 K. Additional irradiation was performed to a fluence of 2 × 1017 (He+ + D+)/cm2 at 773 K. The irradiated pellets were characterized using scanning transmission electron microscopy, time-of-flight secondary ion mass spectrometry, and grazing incidence x-ray diffraction. Lattice damage, amorphization, and fractures are observed with no evidence for the formation of secondary-phase precipitates in the pellets irradiated up to an ion fluence of 2 × 1017 (He+ + D+)/cm2 at 573 K. In contrast, faceted precipitates with sizes larger than 100 nm formed in a pellet irradiated to 2 × 1017 (He+ + D+)/cm2 at 773 K. Analyses of the diffraction and composition data suggest that the precipitates have a spinel-type structure, likely a non-stoichiometric LiAl5O8 with Li depletion. This could be an intermediate phase with Li atoms at the octahedral and possibly tetrahedral sites as well. It is speculated that as the dose increases, Li loss will continue and the precipitates will approach a composition of alumina primarily in phases of α-Al2O3 and amorphized Al2O3.