Ultra-thin multilayer graphene film domain grown on Cu by chemical vapor deposition enables dendrite free lithium deposition in an anode-free Li metal battery via distributing localized current.

Platinum diselenide (PtSe2) is a group-10 two-dimensional (2D) transition metal dichalcogenide that exhibits the most prominent atomic-layer-dependent electronic behavior of “semiconductor-to-semimetal” transition when going from monolayer to bulk form. This work demonstrates an efficient photoelectrochemical (PEC) conversion for direct solar-to-hydrogen (H2) production based on 2D layered PtSe2/Si heterojunction photocathodes. By systematically controlling the number of atomic layers of wafer-scale 2D PtSe2 films through chemical vapor deposition (CVD), the interfacial band alignments at the 2D layered PtSe2/Si heterojunctions can be appropriately engineered. The 2D PtSe2/p-Si heterojunction photocathode consisting of a PtSe2 thin film with a thickness of 2.2 nm (or 3 atomic layers) exhibits the optimized band alignment and delivers the best PEC performance for hydrogen production with a photocurrent density of −32.4 mA cm–2 at 0 V and an onset potential of 1 mA cm–2 at 0.29 V versus a reversible hydrogen electrode (RHE) after post-treatment. The wafer-scale atomic-layer controlled band engineering of 2D PtSe2 thin-film catalysts integrated with the Si light absorber provides an effective way in the renewable energy application for direct solar-to-hydrogen production.

Review: Es wird eine Übersicht über die spezifische Leitfähigkeit und die Aktivierungsenergie der Leitfähigkeit von Oxidgläsern mit einem Gehalt von mehr als ein paar Prozent an Übergangsmetallionen N1 Co) gegeben . Der Mechanismus der Elektronenleitung (V, Fe, Ti, Mo, W, Cu, Mn, ′, beruht auf einer Ladungsübertragung zwischen den Ionen mit verschiedener Wertigkeit.

The adsorption and desorption of electrolyte ions strongly modulates the carrier density or carrier type on the surface of monolayer-MoS2 catalyst during the hydrogen evolution reaction (HER). The buildup of electrolyte ions onto the surface of monolayer MoS2 during the HER may also result in the formation of excitons and trions, similar to those observed in gate-controlled field-effect transistor devices. Using the distinct carrier relaxation dynamics of excitons and trions of monolayer MoS2 as sensitive descriptors, an in situ microcell-based scanning time-resolved liquid cell microscope is set up to simultaneously measure the bias-dependent exciton/trion dynamics and spatially map the catalytic activity of monolayer MoS2 during the HER. This operando probing technique used to monitor the interplay between exciton/trion dynamics and electrocatalytic activity for two-dimensional transition metal dichalcogenides provides an excellent platform to investigate the local carrier behaviors at the atomic layer/liquid electrolyte interfaces during electrocatalytic reaction.

In article number 1901022, Di‐Yan Wang, Bing Joe Hwang, Chun‐Wei Chen and co‐workers demonstrate a novel three‐dimensional pyramid‐like graphene/p‐Si Schottky junction photocathode for H2 production. The formation of graphene/Si Schottky junctions with a 3D architecture is a promising approach to improve the performance and durability of Si‐based photoelectrochemical systems for water splitting or solar‐to‐fuel conversion.