Optimized Adsorption of H and OH over Amorphous SrRuPtOH Nanobelts towards Efficient Alkaline Fuel Cell Catalysis.

PtRu-based catalysts toward hydrogen oxidation reaction (HOR) suffer from low efficiency, CO poisoning and over-oxidation at high potentials. In this work, an amorphization strategy is adopted for preparation of amorphous SrRuPtOH nanobelts (a-SrRuPtOH NBs). The a-SrRuPtOH NBs has optimized adsorption of intermediates (H and OH), increased number of active sites, highly weakened CO poisoning and enhanced anti-oxidation ability owing to the special amorphous structure.

Ultrathin Ternary FeCoNi Alloy Nanoarrays in BaTiO Matrix for Room-Temperature Multiferroic and Hyperbolic Metamaterial.

Multifunctional vertically aligned nanocomposite (VAN) thin films exhibit considerable potential in diverse fields. Here, a BaTiO-FeCoNi alloy (BTO-FCN) system featuring an ultrathin ternary FCN alloy nanopillar array embedded in the BTO matrix has been developed with tailorable nanopillar size and interpillar distance. The magnetic alloy nanopillars combined with a ferroelectric oxide matrix present intriguing multifunctionality and coupling properties.

Strain and Surface Engineering of Multicomponent Metallic Nanomaterials with Unconventional Phases.

Multicomponent metallic nanomaterials with unconventional phases show great prospects in electrochemical energy storage and conversion, owing to unique crystal structures and abundant structural effects. In this review, we emphasize the progress in the strain and surface engineering of these novel nanomaterials. We start with a brief introduction of the structural configurations of these materials, based on the interaction types between the components.

Alkylamine-Confined Thickness-Tunable Synthesis of Co(OH)-CoO Nanosheets toward Oxygen Evolution Catalysis.

Thickness regulation of transition metal hydroxides/oxides nanosheets with superior catalytic properties represents a promising strategy to enhance catalytic performance, but it remains an enormous challenge to achieve precise control, especially when it comes to the ultrathin limit (several atomic layers). In this work, a facile strategy of alkylamine-confined growth is proposed for the synthesis of thickness-tunable metal hydroxide/oxide nanosheets. Specifically, ultrathin cobalt hydroxide and cobaltous oxide hybrid (Co(OH)-CoO) nanosheets (Co-O NSs) with a thickness in the range of 2-6 nm (5-13 atomic layers) are synthesized by using alkylamines with different carbon chain lengths as the ligand to modulate vertical coordination ability.

Highly Selective CO Electroreduction to C Products over CuO-Decorated 2D Metal-Organic Frameworks with Rich Heterogeneous Interfaces.

The electroreduction of carbon dioxide into high-value-added products is an effective approach to alleviating the energy crisis and pollution issues. However, there are still significant challenges for multicarbon (C) product production due to the lack of efficient catalysts with high selectivity. Herein, a Cu-rich electrocatalyst, where CuO nanoparticles are decorated on two-dimensional (2D) Cu-BDC metal-organic frameworks (MOFs) with abundant heterogeneous interfaces, is synthesized for highly selective CO electroreduction into C products.

Medium/High-Entropy Amalgamated Core/Shell Nanoplate Achieves Efficient Formic Acid Catalysis for Direct Formic Acid Fuel Cell.

High-entropy alloys (HEAs) have been attracting extensive research interests in designing advanced nanomaterials, while their precise control is still in the infancy stage. Herein, we have reported a well-defined PtBiPbNiCo hexagonal nanoplates (HEA HPs) as high-performance electrocatalysts. Structure analysis decodes that the HEA HP is constructed with PtBiPb medium-entropy core and PtBiNiCo high-entropy shell.

Phase Engineering of a Ruthenium Nanostructure toward High-Performance Bifunctional Hydrogen Catalysis.

The physicochemical properties and catalytic performance of transition metals are highly phase-dependent. Ru-based nanomaterials are superior catalysts toward hydrogen evolution reaction (HER) and hydrogen oxidation reaction (HOR), but studies are mostly limited to conventional hexagonal-close-packed (hcp) Ru, mainly arising from the difficulty in synthesizing Ru with pure face-centered-cubic (fcc) phase. Herein, we report a crystal-phase-dependent catalytic study of MoO-modified Ru (MoO-Ru fcc and MoO-Ru hcp) for bifunctional HER and HOR.

Reducing leakage current and enhancing polarization in multiferroic 3D super-nanocomposites by microstructure engineering.

Multiferroic materials have generated great interest due to their potential as functional device materials. Nanocomposites have been increasingly used to design and generate new functionalities by pairing dissimilar ferroic materials, though the combination often introduces new complexity and challenges unforeseeable in single-phase counterparts. The recently developed approaches to fabricate 3D super-nanocomposites (3D-sNC) open new avenues to control and enhance functional properties.

Single-site Pt-doped RuO hollow nanospheres with interstitial C for high-performance acidic overall water splitting.

Realizing stable and efficient overall water splitting is highly desirable for sustainable and efficient hydrogen production yet challenging because of the rapid deactivation of electrocatalysts during the acidic oxygen evolution process. Here, we report that the single-site Pt-doped RuO hollow nanospheres (SS Pt-RuO HNSs) with interstitial C can serve as highly active and stable electrocatalysts for overall water splitting in 0.5 M HSO.

Compensating Electronic Effect Enables Fast Site-to-Site Electron Transfer over Ultrathin RuMn Nanosheet Branches toward Highly Electroactive and Stable Water Splitting.

To improve the electroactivity and stability of electrocatalysts, various modulation strategies have been applied in nanocatalysts. Among different methods, heteroatom doping has been considered as an effective method, which modifies the local bonding environments and the electronic structures. Meanwhile, the design of novel two-dimensional (2D) nanostructures also offers new opportunities for achieving efficient electrocatalysts.

Highly Surface-Distorted Pt Superstructures for Multifunctional Electrocatalysis.

Platinum (Pt) catalysts play a key role in energy conversion and storage processes, but the realization of further performance enhancement remains challenging. Herein, we report a new class of Pt superstructures (SSs) with surface distortion engineering by electrochemical leaching of PtTe SSs that can largely boost the oxygen reduction reaction (ORR), the methanol oxidation reaction (MOR), and the hydrogen evolution reaction (HER). In particular, the high-distortion (H)-Pt SSs achieve a mass activity of 2.

A Top-Down Strategy to Realize Surface Reconstruction of Small-Sized Platinum-Based Nanoparticles for Selective Hydrogenation.

Over the past decades, despite the substantial efforts that have been devoted to the modifications of Pt nanoparticles (NPs) to tailor their selectivities for hydrogenation reactions, there are still a lack of facile strategies for precisely regulation of the surface properties of NPs, especially for those with small sizes. In this work, we propose a top-down thermal annealing strategy for tuning the surface properties of Pt-based NPs (≈4 nm) without the occurrence of aggregation. Compared to conventional bottom-up methods, the present top-down strategy can precisely regulate the surface compositions of Pt-Cd NPs and other ternary Pt-Cd-M NPs (M=Fe, Ni, Co, Mn, and Sn).

Recent Progress in Advanced Electrocatalyst Design for Acidic Oxygen Evolution Reaction.

Proton exchange membrane (PEM) water electrolyzers hold great significance for renewable energy storage and conversion. The acidic oxygen evolution reaction (OER) is one of the main roadblocks that hinder the practical application of PEM water electrolyzers. Highly active, cost-effective, and durable electrocatalysts are indispensable for lowering the high kinetic barrier of OER to achieve boosted reaction kinetics.

Grain-Boundary-Engineered LaCuO Perovskite Nanobamboos for Efficient CO Reduction Reaction.

Electroreduction of carbon dioxide (CORR) has been regarded as a promising approach to realize the production of useful fuels and to decrease greenhouse gas levels simultaneously, where high-efficiency catalysts are required. Herein, we report LaCuO nanobamboo (LaCuO NBs) perovskite with rich twin boundaries showing a high Faraday efficiency (FE) of 60% toward ethylene (CH), whereas bulk LaCuO exhibits a FE of 91%. X-ray absorption spectroscopy (XAS) reveals that the Cu in LaCuO NBs is in the Cu state, and no obvious change can be observed during the catalytic process, as monitored by XAS.

Te-Doped Pd Nanocrystal for Electrochemical Urea Production by Efficiently Coupling Carbon Dioxide Reduction with Nitrite Reduction.

The renewable electricity-driven reduction of carbon dioxide (CORR) is a promising technology for carbon utilization. However, it is still a challenge to broaden the application of CORR. Herein, we report a Te-doped Pd nanocrystals (Te-Pd NCs) for promoting urea synthesis by coupling CORR with electrochemical reduction of nitrite.

Induced ferroelectric phases in SrTiO by a nanocomposite approach.

Inducing new phases in thick films via vertical lattice strain is one of the critical advantages of vertically aligned nanocomposites (VANs). In SrTiO (STO), the ground state is ferroelastic, and the ferroelectricity in STO is suppressed by the orthorhombic transition. Here, we explore whether vertical lattice strain in three-dimensional VANs can be used to induce new ferroelectric phases in SrTiO:MgO (STO:MgO) VAN thin films.

Partially hydroxylated ultrathin iridium nanosheets as efficient electrocatalysts for water splitting.

Ultrathin two-dimensional (2D) materials have attracted considerable attention for their unique physicochemical properties and promising applications; however, preparation of freestanding ultrathin 2D noble metal remains a significant challenge. Here, for the first time, we report use of a wet-chemical method to synthesize partially hydroxylated ultrathin Ir nanosheets (Ir-NSs) of only five to six atomic layers' thickness. Detailed analysis indicates that the growth confinement effect of carbon monoxide and the partially hydroxylated surface play a critical role in formation of the ultrathin structure.

Cation Exchange Strategy to Single-Atom Noble-Metal Doped CuO Nanowire Arrays with Ultralow Overpotential for HO Splitting.

Single-atom site catalysts (SACs) have aroused enormous attention and brought about new opportunities for many applications. Herein, we report a versatile strategy to rhodium (Rh) SAC by a facile cation exchange reaction. Remarkably, the Rh SAC modified CuO nanowire arrays on copper foam (Rh SAC-CuO NAs/CF) show unprecedented alkaline oxygen evolution reaction (OER) activity with a high current density of 84.

Metallic nanostructures with low dimensionality for electrochemical water splitting.

Metallic nanostructures with low dimensionality (one-dimension and two-dimension) possess unique structural characteristics and distinctive electronic and physicochemical properties including high aspect ratio, high specific surface area, high density of surface unsaturated atoms and high electron mobility. These distinctive features have rendered them remarkable advantages over their bulk counterparts for surface-related applications, for example, electrochemical water splitting. In this review article, we highlight the recent research progress in low-dimensional metallic nanostructures for electrochemical water splitting including hydrogen evolution reaction (HER) and oxygen evolution reaction (OER).

Novel layered BiMoMO (M = Mn, Fe, Co and Ni) thin films with tunable multifunctionalities.

Bi3MoMTO9 (BMoMTO; MT, transition metals of Mn, Fe, Co and Ni) thin films with a layered supercell structure have been deposited on LaAlO3 (001) substrates by pulsed laser deposition. Microstructural analysis suggests that pillar-like domains with higher transition metal concentration (e.g.

Surface-Regulated Rhodium-Antimony Nanorods for Nitrogen Fixation.

Surface regulation is an effective strategy to improve the performance of catalysts, but it has been rarely demonstrated for nitrogen reduction reaction (NRR) to date. Now, surface-rough Rh Sb nanorod (RNR) and surface-smooth Rh Sb NR (SNR) were selectively created, and their performance for NRR was investigated. The high-index-facet bounded Rh Sb RNRs/C exhibit a high NH yield rate of 228.

Crystal-Phase-Engineered PdCu Electrocatalyst for Enhanced Ammonia Synthesis.

Crystal phase engineering is a powerful strategy for regulating the performance of electrocatalysts towards many electrocatalytic reactions, while its impact on the nitrogen electroreduction has been largely unexplored. Herein, we demonstrate that structurally ordered body-centered cubic (BCC) PdCu nanoparticles can be adopted as active, selective, and stable electrocatalysts for ammonia synthesis. Specifically, the BCC PdCu exhibits excellent activity with a high NH yield of 35.