No abstract

Here we reported single-crystalline molecular crystal melem nanorods with modulated charge potentials and dynamics due to the high-crystallinity and low-dimensionality facilitating transport of photo-induced carriers.

A Ag3Cu/TiO2/ZnTe photocathode which integrates fast interface-carrier migration, catalytic selectivity, and stability was fabricated for solar-driven CO2 reduction to tunable syngas.

Catalysts based on Cu nanocrystals (NCs) for electrochemical CO 2 -to-C 2+ conversion with high activity have been a subject of considerable interest, but poor stability and low selectivity for a single C 2+ product remain obstacles for realizing sustainable carbon-neutral cycles. Here, we used the facet-selective atomic layer deposition (FS-ALD) technique to selectively cover the (111) surface of Cu NCs with ultrathin Al 2 O 3 to increase the exposed facet ratio of (100)/(111), resulting in a faradaic efficiency ratio of C 2 H 4 /CH 4 for overcoated Cu NCs 22 times higher than that for pure Cu NCs. Peak performance of the overcoated catalyst (Cu NCs/ Al 2 O 3 -10C) reaches a C 2 H 4 faradaic efficiency of 60.4 % at a current density of 300 mA cm À2 in 5 M KOH electrolyte, when using a gas diffusion electrode flow cell. Moreover, the Al 2 O 3 overcoating effectively suppresses the dynamic mobility and the aggregation of Cu NCs, which explains the negligible activity loss and selectivity degradations of Cu NCs/Al 2 O 3 -10C shown in stability tests.

Rechargeable Zn−air batteries are a promising type of metal-air batteries for high-density energy storage. However, their practical use is limited by the use of costly noble-metal electrocatalysts for the sluggish kinetics of the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) occurred at the air electrode of the Zn−air batteries. This work reports a new non-precious bifunctional OER/ORR electrocatalyst of NiS x /carbon nanotubes (CNTs), which is made by atomic layer deposition (ALD) of nickel sulfide (NiS x ) on CNTs, for the applications for the air electrode of the Zn−air batteries. The NiS x /CNT electrocatalyst on a carbon cloth electrode exhibits a low OER overpotential of 288 mV to reach 10 mA cm−2 in current density, and the electrocatalyst on a rotating disk electrode exhibits a half-wave ORR potential of 0.81 V in alkaline electrolyte. With the use of the NiS x /CNT electrocatalyst for the air electrode, the fabricated aqueous rechargeable Zn−air batteries show a fairly good maximum output power density of 110 mW cm−2, which highlights the great promise of the ALD NiS x /CNT electrocatalyst for Zn−air batteries.