Electronic Interaction Enables Pt Nanoparticles on N-Doped Porous Carbon Aerogel as Efficient Electrocatalysts for Alkaline Hydrogen Evolution Reaction.

Alkaline water electrolysis for hydrogen evolution reaction (HER) with Pt-based electrocatalysts as the cathodes is still sluggish due to the unfavorable activation of water. Herein, the three-dimensional N-doped carbon aerogel (NCA) is adopted as the defect-rich support for uniform loading of ultra-fine Pt nanoparticles to prepare Pt/NCA for alkaline HER. Doping N into carbon aerogel (CA) promotes the strong electronic interaction between Pt nanoparticles and NCA, thus resulting in the electron transfer from Pt to NCA to optimize the free energy for hydrogen adsorption and facilitate the adsorption and dissociation of water.

Optimizing C─C Coupling on Cu/Cu/Ga Interfaces by Enhancing Active Hydrogen Absorption for Excellent CO-to-C Electrosynthesis.

The electrocatalytic reduction of CO (CORR) to high-value chemicals and fuels offers a promising route for a clean carbon cycle. However, it often suffers from low catalytic activity and poor selectivity. Heterostructure construction has been shown to be an effective strategy for producing multi-carbon products, but the synergistic mechanisms between multiple active sites resulting from the reconstruction process remain unclear.

Controlling Surface Chemical Inhomogeneity of Ni P/MoNiP /MoP Heterostructure Electrocatalysts for Efficient Hydrogen Evolution Reaction.

Crystalline/amorphous phase engineering is demonstrated as a powerful strategy for electrochemical performance optimization. However, it is still a considerable challenge to prepare transition metal-based crystalline/amorphous heterostructures because of the low redox potential of transition metal ions. Herein, a facile H -assisted method is developed to prepare ternary Ni P/MoNiP /MoP crystalline/amorphous heterostructure nanowires on the conductive substrate.

Ultralow-iridium content NiIr alloy derivative nanochain arrays as bifunctional electrocatalysts for overall water splitting.

The development of low-cost and high-durability bifunctional electrocatalysts is of considerable importance for overall water splitting (OWS). This work reports the controlled synthesis of nickel-iridium alloy derivative nanochain array electrodes (NiIr NCs) with fully exposed active sites that facilitated mass transfer for efficient OWS. The nanochains have a self-supported three-dimensional core-shell structure, composed of a metallic NiIr core and a thin (5-10 nm) amorphous (hydr)oxide film as the shell (, IrO/NiIr and Ni(OH)/NiIr).

Van der Waals nanomesh electronics on arbitrary surfaces.

Chemical bonds, including covalent and ionic bonds, endow semiconductors with stable electronic configurations but also impose constraints on their synthesis and lattice-mismatched heteroepitaxy. Here, the unique multi-scale van der Waals (vdWs) interactions are explored in one-dimensional tellurium (Te) systems to overcome these restrictions, enabled by the vdWs bonds between Te atomic chains and the spontaneous misfit relaxation at quasi-vdWs interfaces. Wafer-scale Te vdWs nanomeshes composed of self-welding Te nanowires are laterally vapor grown on arbitrary surfaces at a low temperature of 100 °C, bringing greater integration freedoms for enhanced device functionality and broad applicability.

Contact Engineering of Halide Perovskites: Gold is Not Good Enough; Metalloid is Better.

The operation stability of halide perovskite devices is the critical issue that impedes their commercialization. The main reasons are that the ambient H O molecules can easily deteriorate the perovskites, while the metal electrodes react in different degrees with the perovskites. Herein, one kind of new electrode, the metalloids, is reported, which are much more stable than the conventional noble metals as electrical contacts for halide perovskites.

Mixed-Dimensional Anti-ambipolar Phototransistors Based on 1D GaAsSb/2D MoS Heterojunctions.

The incapability of modulating the photoresponse of assembled heterostructure devices has remained a challenge for the development of optoelectronics with multifunctionality. Here, a gate-tunable and anti-ambipolar phototransistor is reported based on 1D GaAsSb nanowire/2D MoS nanoflake mixed-dimensional van der Waals heterojunctions. The resulting heterojunction shows apparently asymmetric control over the anti-ambipolar transfer characteristics, possessing potential to implement electronic functions in logic circuits.

Self-Anti-Stacking 2D Metal Phosphide Loop-Sheet Heterostructures by Edge-Topological Regulation for Highly Efficient Water Oxidation.

2D metal phosphide loop-sheet heterostructures are controllably synthesized by edge-topological regulation, where Ni P nanosheets are edge-confined by the N-doped carbon loop, containing ultrafine NiFeP nanocrystals (denoted as NiFeP@NC/Ni P). This loop-sheet feature with lifted-edges prevents the stacking of nanosheets and induces accessible open channels for catalytic site exposure and gas bubble release. Importantly, these NiFeP@NC/Ni P hybrids exhibit a remarkable oxygen evolution activity with an overpotential of 223 mV at 20 mA cm and a Tafel slope of 46.

Gate Bias Stress Instability and Hysteresis Characteristics of InAs Nanowire Field-Effect Transistors.

Because of the excellent electrical properties, III-V semiconductor nanowires are promising building blocks for next-generation electronics; however, their rich surface states inevitably contribute large amounts of charge traps, leading to gate bias stress instability and hysteresis characteristics in nanowire field-effect transistors (FETs). Here, we investigated thoroughly the gate bias stress and hysteresis effects in InAs nanowire FETs. It is observed that the output current decreases together with the threshold voltage shifting to the positive direction when a positive gate bias stress is applied, and vice versa for the negative gate bias stress.

Artificial visual systems enabled by quasi-two-dimensional electron gases in oxide superlattice nanowires.

Rapid development of artificial intelligence techniques ignites the emerging demand on accurate perception and understanding of optical signals from external environments via brain-like visual systems. Here, enabled by quasi-two-dimensional electron gases (quasi-2DEGs) in InGaO(ZnO) superlattice nanowires (NWs), an artificial visual system was built to mimic the human ones. This system is based on an unreported device concept combining coexistence of oxygen adsorption-desorption kinetics on NW surface and strong carrier quantum-confinement effects in superlattice core, to resemble the biological Ca ion flux and neurotransmitter release dynamics.

Perovskite Core-Shell Nanowire Transistors: Interfacial Transfer Doping and Surface Passivation.

While halide perovskite electronics are rapidly developing, they are greatly limited by the inferior charge transport and poor stability. In this work, effective surface charge transfer doping of vapor-liquid-solid (VLS)-grown single-crystalline cesium lead bromide perovskite (CsPbBr) nanowires (NWs) molybdenum trioxide (MoO) surface functionalization is achieved. Once fabricated into NW devices, due to the efficient interfacial charge transfer and reduced impurity scattering, a 15× increase in the field-effect hole mobility (μ) from 1.

Bication-Mediated Quasi-2D Halide Perovskites for High-Performance Flexible Photodetectors: From Ruddlesden-Popper Type to Dion-Jacobson Type.

Quasi-2D halide perovskites, especially the Ruddlesden-Popper perovskites (RPPs), have attracted great attention because of their promising properties for optoelectronics; however, there are still serious drawbacks, such as inefficient charge transport, poor stability, and unsatisfactory mechanical flexibility, restricting further utilization in advanced technologies. Herein, high-quality quasi-2D halide perovskite thin films are successfully synthesized with the introduction of the unique bication ethylenediammonium (EDA) via a one-step spin-coating method. This bication EDA, with short alkyl chain length, can not only substitute the typically bulky and weakly van der Waals-interacted organic bilayer spacer cations forming the novel Dion-Jacobson phase to enhance the mechanical flexibility of the quasi-2D perovskite (e.

High-mobility In and Ga co-doped ZnO nanowires for high-performance transistors and ultraviolet photodetectors.

Due to their unique properties, ZnO nanostructures have received considerable attention for application in electronics and optoelectronics; however, intrinsic ZnO nanomaterials usually suffer from large concentrations of lattice defects, such as oxygen vacancies, which restricts their material performance. Here, for the first time, highly-crystalline In and Ga co-doped ZnO nanowires (NWs) are achieved by ambient-pressure chemical vapor deposition. In contrast to conventional elemental doping, this In and Ga co-doping can not only enhance the carrier concentration, but also suppresses the formation of oxygen vacancies within the host lattice of ZnO NWs.

Two-Dimensional Cobalt Phosphate Hydroxide Nanosheets: A New Type of High-Performance Electrocatalysts with Intrinsic CoO Lattice Distortion for Water Oxidation.

Despite the recent advances in electrochemical water splitting, developing cost-effective and highly efficient electrocatalysts for oxygen evolution reaction (OER) still remains a substantial challenge. Herein, two-dimensional cobalt phosphate hydroxides (Co(PO)(OH)) nanosheets, a unique stacking-disordered phosphate-based inorganic material, are successfully prepared via a facile and scalable method for the first time to serve as a superior and robust electrocatalyst for water oxidation. On the basis of the detailed characterization (e.

Engineering Surface Structure of Spinel Oxides via High-Valent Vanadium Doping for Remarkably Enhanced Electrocatalytic Oxygen Evolution Reaction.

Spinel oxides (ABO) with unique crystal structures have been widely explored as promising alternative catalysts for efficient oxygen evolution reactions; however, developing novel methods to fabricate robust, cost-effective, and high-performance spinel oxide based electrocatalysts is still a great challenge. Here, utilizing a complementary experimental and theoretical approach, pentavalent vanadium doping in the spinel oxides (i.e.

High-Index Faceted Porous CoO Nanosheets with Oxygen Vacancies for Highly Efficient Water Oxidation.

Because of sluggish kinetics of the oxygen evolution reaction (OER), designing low-cost, highly active, and stable electrocatalysts for OER is important for the development of sustainable electrochemical water splitting. Here, {112} high-index facet exposed porous CoO nanosheets with oxygen vacancies on the surface have been successfully synthesized via a simple hydrothermal method followed by NaBH reduction. As compared with the pristine and other faceted porous CoO nanosheets (e.

Surface Modification of CN through Oxygen-Plasma Treatment: A Simple Way toward Excellent Hydrophilicity.

We developed a universal method to prepare hydrophilic carbon nitrogen (CN) nanosheets. By treating CN nanosheets with oxygen plasma, hydroxylamine groups (N-OH) with intense protonation could be introduced on the surface; moreover, the content of N-OH groups increased linearly with the oxygen-plasma treatment time. Thanks to the excellent hydrophilicity, uniformly dispersed CN solution were prepared, which was further translated into CN paper by simple vacuum filtration.

A New Graphene Derivative: Hydroxylated Graphene with Excellent Biocompatibility.

Graphene derivatives (such as graphene oxide and hydrogenated graphene) have been widely investigated because of their excellent properties. Here, we report large-scale (kilogram scale) synthesis of a new unique graphene derivative: hydroxylated graphene (G-OH). The exclusive existence form of oxygen-containing groups in G-OH is hydroxyl, which was verified by spectral characterization and quantitative halogenating reaction.