Pulse Electrolysis Turns on CO Methanation through N-Confused Cupric Porphyrin.

Breaking the D symmetry in the square-planar M-N configuration of macrocycle molecular catalysts has witnessed enhanced electrocatalytic activity, but at the expense of electrochemical stability. Herein, we hypothesize that the lability of the active Cu-N motifs in the N-confused copper (II) tetraphenylporphyrin (CuNCP) could be overcome by applying pulsed potential electrolysis (PPE) during electrocatalytic carbon dioxide reduction. We find that applying PPE can indeed enhance the CH selectivity on CuNCP by 3 folds to reach the partial current density of 170 mA cm at >60 % Faradaic efficiency (FE) in flow cell.

Proton Shuttling by Polyaniline of High Brønsted Basicity for Improved Electrocatalytic Ethylene Production from CO.

Hybrid organic/inorganic composites with the organic phase tailored to modulate local chemical environment at the Cu surface arise as an enchanting category of catalysts for electrocatalytic CO reduction reaction (CO RR). A fundamental understanding on how the organics of different functionality, polarity, and hydrophobicity affect the reaction path is, however, still lacking to guide rational catalyst design. Herein, polypyrrole (PPy) and polyaniline (PANI) manifesting different Brønsted basicity are compared for their regulatory roles on the CO RR pathways regarding *CO coverage, proton source and interfacial polarity.

The Role of Bismuth in Suppressing the CO Poisoning in Alkaline Methanol Electrooxidation: Switching the Reaction from the CO to Formate Pathway.

While tuning the electronic structure of Pt can thermodynamically alleviate CO poisoning in direct methanol fuel cells, the impact of interactions between intermediates on the reaction pathway is seldom studied. Herein, we contrive a PtBi model catalyst and realize a complete inhibition of the CO pathway and concurrent enhancement of the formate pathway in the alkaline methanol electrooxidation. The key role of Bi is enriching OH adsorbates (OH) on the catalyst surface.

Bismuth Oxyhydroxide-Pt Inverse Interface for Enhanced Methanol Electrooxidation Performance.

Developing efficient Pt-based electrocatalysts for the methanol oxidation reaction (MOR) is of pivotal importance for large-scale application of direct methanol fuel cells (DMFCs), but Pt suffers from severe deactivation brought by the carbonaceous intermediates such as CO. Here, we demonstrate the formation of a bismuth oxyhydroxide (BiO(OH))-Pt inverse interface via electrochemical reconstruction for enhanced methanol oxidation. By combining density functional theory calculations, X-ray absorption spectroscopy, ambient pressure X-ray photoelectron spectroscopy, and electrochemical characterizations, we reveal that the BiO(OH)-Pt inverse interface can induce the electron deficiency of neighboring Pt; this would result in weakened CO adsorption and strengthened OH adsorption, thereby facilitating the removal of the poisonous intermediates and ensuring the high activity and good stability of PtBi sample.

Integrated Evaporator for Efficient Solar-Driven Interfacial Steam Generation.

Solar-driven interfacial steam generation is a promising technique for clean water production because it can minimize thermal loss by localizing solar-to-heat conversion at the air/liquid interface. Here we report an integrated solar evaporator by partially growing 2D polypyrrole microsheets within a melamine foam through chemical vapor polymerization. These microsheets can induce multiple light reflections within the foam, enable omnidirectional light absorption, provide abundant surfaces to promote heat transfer, and achieve spatially defined hydrophobicity to facilitate vapor escape.

Encapsulated Metal Nanoparticles for Catalysis.

Metal nanoparticles have drawn great attention in heterogeneous catalysis. One challenge is that they are easily deactivated by migration-coalescence during the catalysis process because of their high surface energy. With the rapid development of nanoscience, encapsulating metal nanoparticles in nanoshells or nanopores becomes one of the most promising strategies to overcome the stability issue of the metal nanoparticles.

Bi(OH)/PdBi Composite Nanochains as Highly Active and Durable Electrocatalysts for Ethanol Oxidation.

Developing high-performance electrocatalysts for the ethanol oxidation reaction (EOR) is critical to the commercialization of direct ethanol fuel cells. However, current EOR catalysts suffer from high cost, low activity, and poor durability. Here we report the preparation of PdBi-Bi(OH) composite nanochains with outstanding EOR activity and durability.

Self-Aligned Anisotropic Plasmonic Nanostructures.

Great opportunities emerge not only in the generation of anisotropic plasmonic nanostructures but also in controlling their orientation relative to incident light. Herein, a stepwise seeded growth method is reported for the synthesis of rod-shaped plasmon nanostructures which are vertically self-aligned with respect to the surface of colloidal substrates. Anisotropic growth of metal nanostructure is achieved by depositing metal seeds onto the surface of colloidal substrates and then selectively passivating the seed surface to induce symmetry breaking in the subsequent seed-mediated growth process.

Noble-Metal-Free Electrocatalysts for Oxygen Evolution.

Oxygen evolution reaction (OER) plays a vital role in many energy conversion and storage processes including electrochemical water splitting for the production of hydrogen and carbon dioxide reduction to value-added chemicals. IrO and RuO , known as the state-of-the-art OER electrocatalysts, are severely limited by the high cost and low earth abundance of these noble metals. Developing noble-metal-free OER electrocatalysts with high performance has been in great demand.

In situ one-step synthesis of FeO@MIL-100(Fe) core-shells for adsorption of methylene blue from water.

A new route for FeO@MIL-100(Fe) core-shells is proposed via in situ one-step hydrothermal strategy, in which FeO microspheres not only serve as magnetic cores but also provide Fe(III) for MIL-100(Fe) synthesis. The MIL-100(Fe) is uniformly grown as a shell on the surface of FeO, and the shell thickness can be fine-tuned from 73.5 to 148nm by simply controlling the reaction time.

Phase-controllable synthesis of cobalt hydroxide for electrocatalytic oxygen evolution.

Identification of active sites for oxygen evolution reaction (OER) plays a key role in the design and fabrication of high-performance cobalt-based electrocatalysts. Herein, we report the synthesis of two types of two-dimensional monometallic cobalt hydroxide nanoplates in aqueous solution for OER: α-Co(OH) with both Co and Co sites and β-Co(OH) with Co sites. Electrochemical characterization reveals that α-Co(OH) is more active than β-Co(OH) towards OER.

Photocatalytic Color Switching of Transition Metal Hexacyanometalate Nanoparticles for High-Performance Light-Printable Rewritable Paper.

Developing efficient photoreversible color switching systems for constructing rewritable paper is of significant practical interest owing to the potential environmental benefits including forest conservation, pollution reduction, and resource sustainability. Here we report that the color change associated with the redox chemistry of nanoparticles of Prussian blue and its analogues could be integrated with the photocatalytic activity of TiO nanoparticles to construct a class of new photoreversible color switching systems, which can be conveniently utilized for fabricating ink-free, light printable rewritable paper with various working colors. The current system also addresses the phase separation issue of the previous organic dye-based color switching system so that it can be conveniently applied to the surface of conventional paper to produce an ink-free light printable rewritable paper that has the same feel and appearance as the conventional paper.

Design of two-dimensional, ultrathin MoS₂ nanoplates fabricated within one-dimensional carbon nanofibers with thermosensitive morphology: high-performance electrocatalysts for the hydrogen evolution reaction.

Two-dimensional MoS2 nanoplates within carbon nanofibers (CNFs) with monolayer thickness, nanometer-scale dimensions and abundant edges are fabricated. This strategy provides a well-defined pathway for the precise design of MoS2 nanomaterials, offering control over the evolution of MoS2 morphology from nanoparticles to nanoplates as well as from mono- to several-layer structures, over a lateral dimension range of 5 to 70 nm. CNFs play an important role in confining the growth of MoS2 nanoplates, leading to increases in the amount of exposed edge sites while hindering the stacking and aggregation of MoS2 layers, and accelerating electron transfer.