Built-in Electric Field Within CoSe-FeSe Heterostructure for Enhanced Sulfur Reduction Reaction in Li-S Batteries.

The conversion of LiS to LiS is the most important and slowest rate-limiting step in the complex sulfur reduction reaction (SRR) for Li-S batteries, the adjustment of which can effectively inhibit the notorious "shuttle effect". Herein, a CoSe-FeSe heterostructure embedded in 3D N-doped nanocage as a modified layer on commercial separator is designed (CoSe-FeSe@NC//PP). The CoSe-FeSe heterostructure forms a built-in electric field at the two-phase interface, which leads to the optimized adsorption force on polysulfides and the accelerated reaction kinetics for LiS-LiS evolution.

Optimizing Intermediate Adsorption on Pt Sites via Triple-Phase Interface Electronic Exchange for Methanol Oxidation.

For the most commonly applied platinum-based catalysts of direct methanol fuel cells, the adsorption ability toward reaction intermediates, including CO and OH, plays a vital role in their catalytic activity and antipoisoning in anodic methanol oxidation reaction (MOR). Herein, guided by a theoretical mechanism study, a favorable modulation of the electronic structure and intermediate adsorption energetics for Pt active sites is achieved by constructing the triple-phase interfacial structure between tin oxide (SnO), platinum (Pt), and nitrogen-doped graphene (NG). From the strong electronic exchange at the triple-phase interface, the adsorption ability toward MOR reaction intermediates on Pt sites could be efficiently optimized, which not only inhibits the adsorption of CO* on active sites but also facilitates the adsorption of OH* to strip the poisoning species from the catalyst surface.

Controllable Electronic Transfer Tailoring d-band Center via Cobalt-Oxygen-Bridged Ru/Fe Dual-sites for Boosted Oxygen Evolution.

Rational tailoring of the electronic structure at the defined active center of reconstructed metal (oxy)hydroxides (MOOH) during oxygen evolution reaction (OER) remains a challenge. With the guidance of density functional theory (DFT), herein a dual-site regulatory strategy is reported to tailor the d-band center of the Co site in CoOOH via the controlled electronic transfer at the Ru─O─Co─O─Fe bonding structure. Through the bridged O site, electrons are vastly flowed from the t-orbital of the Ru site to the low-spin orbital of the Co site in the Ru-O-Co coordination and further transfer from the strong electron-electron repulsion of the Co site to the Fe site by the Co-O-Fe coordination, which balancing the electronic configuration of Co sites to weaken the over-strong adsorption energy barrier of OH and O, respectively.

Directed Dual Charge Pumping Tunes the d-Orbital Configuration of Pt Cluster Boosting Hydrogen Evolution Kinetic.

Achieving high catalytic activity with a minimum amount of platinum (Pt) is crucial for accelerating the cathodic hydrogen evolution reaction (HER) in proton exchange membrane (PEM) water electrolysis, yet it remains a significant challenge. Herein, a directed dual-charge pumping strategy to tune the d-orbital electronic distribution of Pt nanoclusters for efficient HER catalysis is proposed. Theoretical analysis reveals that the ligand effect and electronic metal-support interactions (EMSI) create an effective directional electron transfer channel for the d-orbital electrons of Pt, which in turn optimizes the binding strength to H*, thereby significantly enhancing HER efficiency of the Pt site.

Co/CoS Heterojunction Embedded in N, S-Doped Hollow Nanocage for Enhanced Polysulfides Conversion in High-Performance Lithium-Sulfur Batteries.

Modulating the electronic configuration of the substrate to achieve the optimal chemisorption toward polysulfides (LiPSs) for boosting polysulfide conversion is a promising way to the efficient Li-S batteries but filled with challenges. Herein, a Co/CoS heterostructure is elaborately built to tuning d-orbital electronic structure of CoS for a high-performance electrocatalyst. Theoretical simulations first evidence that Co metal as the electron donator can form a built-in electric field with CoS and downshift the d-band center, leading to the well-optimized adsorption strength for lithium polysulfides on CoS , thus contributing a favorable way for expediting the redox reaction kinetics of LiPSs.

Tailored Lattice Compressive Strain of Pt-Skins by the L1 -Pt M Intermetallic Core for Highly Efficient Oxygen Reduction.

The sluggish kinetics of oxygen reduction reaction (ORR) and unsatisfactory durability of Pt-based catalysts are severely hindering the commercialization of proton-exchange-membrane fuel cells (PEMFCs). In this work, the lattice compressive strain of Pt-skins imposed by Pt-based intermetallic cores is tailored for highly effective ORR through the confinement effect of the activated nitrogen-doped porous carbon (a-NPC). The modulated pores of a-NPC not only promote Pt-based intermetallics with ultrasmall size (average size of <4 nm), but also efficiently stabilizes intermetallic nanoparticles and sufficient exposure of active sites during the ORR process.

Dual roles of sub-nanometer NiO in alkaline hydrogen evolution reaction: breaking the Volmer limitation and optimizing d-orbital electronic configuration.

Pt-based nanoclusters toward the hydrogen evolution reaction (HER) remain the most promising electrocatalysts. However, the sluggish alkaline Volmer-step kinetics and the high-cost have hampered progress in developing high-performance HER catalysts. Herein, we propose to construct sub-nanometer NiO to tune the d-orbital electronic structure of nanocluster-level Pt for breaking the Volmer-step limitation and reducing the Pt-loading.

Optimizing d-Orbital Electronic Configuration via Metal-Metal Oxide Core-Shell Charge Donation for Boosting Reversible Oxygen Electrocatalysis.

Tuning the d-orbital electronic configuration of active sites to achieve well-optimized adsorption strength of oxygen-containing intermediates toward reversible oxygen electrocatalysis is desirable for efficient rechargeable Zn-Air batteries but extremely challenging. Herein, this work proposes to construct a Co@Co O core-shell structure to regulate the d-orbital electronic configuration of Co O for the enhanced bifunctional oxygen electrocatalysis. Theoretical calculations first evidence that electron donation from Co core to Co O shell could downshift the d-band center and simultaneously weak spin state of Co O , result in the well-optimized adsorption strength of oxygen-containing intermediates on Co O , thus contributing a favor way for oxygen reduction/evolution reaction (ORR/OER) bifunctional catalysis.

PtSn nanoparticles enriched with SnO/PtSn interfaces for highly efficient alcohol electrooxidation.

PtSn nanoparticles (NPs) enriched with PtSn/ultra-small SnO interfaces (PtSn@u-SnO/NG) were synthesized through a thermal treatment of PtSn/NG in a H atmosphere, followed by annealing under H and air conditions. The unique structure of PtSn NPs enriched with PtSn/SnO interfaces was observed on the PtSn@u-SnO/NG catalyst based on HRTEM. The optimized PtSn@u-SnO/NG catalyst achieves high catalytic activity with an ethanol oxidation reaction (EOR) activity of 366 mA mg and a methanol oxidation reaction (MOR) activity of 503 mA mg at the potential of 0.

Enhancement of the performance of Pd nanoclusters confined within ultrathin silica layers for formic acid oxidation.

The optimized design of highly active and stable anode electrocatalysts is essential for high performance direct formic acid fuel cells (DFAFCs). Herein, a facile and cost-effective strategy was proposed to fabricate a robust ultrasmall Pd nanocluster confined within ultrathin protective silica layers anchored on nitrogen doped reduced GO (NrGO) through generating amine functionalized graphene oxide with 3-aminopropyl triethoxysilane (APTES), followed by tuning the thickness of protective silica layers by precisely controlling the amount of tetraethylorthosilicate (TEOS). Amine functionalized graphene oxide generated by using APTES favors the formation of ultrasmall Pd nanoclusters due to the coordination of amine to PdCl24- while the confinement effect of ultrathin protective silica layers stabilizes ultrasmall Pd nanoclusters and impedes the agglomeration and sintering of ultrasmall Pd nanoclusters during electrocatalysis.

Encapsulating Pt Nanoparticles inside a Derived Two-Dimensional Metal-Organic Frameworks for the Enhancement of Catalytic Activity.

The development of highly active and stable electrocatalysts toward oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) is a key for commercial application of fuel cells and water splitting. Here, we report a highly active and stable Pt nanoparticles (NPs) encapsulated in ultrathin two-dimensional (2D) carbon layers derived from the ultrathin 2D metal-organic framework precursor (ZIF-67). Electrochemical tests reveal that our approach not only stabilized Pt NPs successfully but also boosted Pt activities toward ORR and HER.

Highly Active and Durable Ultrasmall Pd Nanocatalyst Encapsulated in Ultrathin Silica Layers by Selective Deposition for Formic Acid Oxidation.

The low performance of palladium (Pd) is a considerable challenge for direct formic acid fuel cells in practical applications. Herein, we develop a simple strategy to synthesize a highly active and durable Pd nanocatalyst encapsulated in ultrathin silica layers with vertically aligned nanochannels covered graphene oxides (Pd/rGO@pSiO) without blocking active sites by selective deposition. The Pd/rGO@pSiO catalyst exhibits very high performance for a formic acid oxidation (FAO) reaction compared with the Pd/rGO without protective silica layers and commercial Pd/C catalysts.

Structurally ordered PtSn intermetallic nanoparticles supported on ATO for efficient methanol oxidation reaction.

The development of cost-effective methanol oxidation reaction (MOR) catalysts with a high activity and stability is highly desirable for direct methanol fuel cells. In this study, the structurally ordered PtSn intermetallic nanoparticles supported on Sb-doped SnO (ATO) have been successfully synthesized in ethylene glycol (EG) solution at 200 °C. Pt NPs were firstly formed on ATO, followed by the transformation from Pt into hexagonal PtSn on the surface of ATO.

Platinum single-atom and cluster catalysis of the hydrogen evolution reaction.

Platinum-based catalysts have been considered the most effective electrocatalysts for the hydrogen evolution reaction in water splitting. However, platinum utilization in these electrocatalysts is extremely low, as the active sites are only located on the surface of the catalyst particles. Downsizing catalyst nanoparticles to single atoms is highly desirable to maximize their efficiency by utilizing nearly all platinum atoms.

Extremely stable platinum nanoparticles encapsulated in a zirconia nanocage by area-selective atomic layer deposition for the oxygen reduction reaction.

Encapsulation of Pt nanoparticles (NPs) in a zirconia nanocage by area-selective atomic layer deposition (ALD) can significantly enhance both the Pt stability and activity. Such encapsulated Pt NPs show 10 times more stability than commercial Pt/C catalysts and an oxygen reduction reaction (ORR) activity 6.4 times greater than that of Pt/C.

Highly active Pt@Au nanoparticles encapsulated in perfluorosulfonic acid for the reduction of oxygen.

The Pt@Au catalysts demonstrate remarkably high oxygen reduction reaction (ORR) activity compared with Pt/C catalysts. The ORR of Pt(2)@Au(1)/C and Pt(1)@Au(2)/C is 9.5 and 6.

Polyaniline-functionalized carbon nanotube supported platinum catalysts.

Electrocatalytically active platinum (Pt) nanoparticles on a carbon nanotube (CNT) with enhanced nucleation and stability have been demonstrated through introduction of electron-conducting polyaniline (PANI) to bridge the Pt nanoparticles and CNT walls with the presence of platinum-nitride (Pt-N) bonding and π-π bonding. The Pt colloids were prepared through ethanol reduction under the protection of aniline, the CNT was dispersed well with the existence of aniline in the solution, and aniline was polymerized in the presence of a protonic acid (HCl) and an oxidant (NH(4)S(2)O(8)). The synthesized PANI is found to wrap around the CNT as a result of π-π bonding, and highly dispersed Pt nanoparticles are loaded onto the CNT with narrowly distributed particle sizes ranging from 2.