Iron-nitrogen on carbon (Fe-N/C) catalysts have emerged as promising nonprecious metal (NPMCs) for oxygen reduction reaction (ORR) in energy conversion and storage devices. It has been widely suggested that an active site structure Fe-N/C contains Fe-Nx coordination. However, the preparation of high-performance mostly involves a high-temperature pyrolysis step, which generates not only catalytically sites, but also less large iron-based particles. Herein, we report general...

A highly efficient, metal-free carbon nanocatalyst is presented that possesses abundant active, oxygenated graphitic edge sites. The site-rich nanocarbon catalyst exhibits about 28 times higher activity for H2 O2 production than a basal plane-rich nanotube with selectivity over 90 %. oxidative treatment further promotes the generation to reach close thermodynamic limit. optimized shows very high activity, surpassing previously reported catalysts in alkaline media. Moreover, it can stably...

The high cost of the platinum-based cathode catalysts for oxygen reduction reaction (ORR) has impeded widespread application polymer electrolyte fuel cells. We report on a new family non-precious metal based ordered mesoporous porphyrinic carbons (M-OMPC; M = Fe, Co, or FeCo) with surface areas and tunable pore structures, which were prepared by nanocasting silica templates metalloporphyrin precursors. FeCo-OMPC catalyst exhibited an excellent ORR activity in acidic medium, higher than other...

We report the use of noble metal-free ordered mesoporous Co3O4 spinels (meso-Co3O4), templated from KIT-6 silica, as highly active and stable bifunctional electrocatalysts for both oxygen evolution reduction reactions (OER ORR, respectively). The meso-Co3O4 nanostructures showed high activity OER in an alkaline medium (0.1 M KOH), which makes them comparable to most Ir/C catalyst better than nanoparticles (NPs) Pt/C catalyst. Furthermore, exhibited enhanced stability, compared NPs. stability...

Nanoframe electrocatalysts have attracted great interest due to their inherently high active surface area per a given mass. Although recent progress has enabled the preparation of single nanoframe structures with variety morphologies, more complex such as double-layered not yet been realized. Herein, we report rational synthetic strategy for structurally robust Ir-based multimetallic (DNF) structure, nanoframe@nanoframe. By leveraging differing kinetics dual Ir precursors and transition...

Triple perovskite, Nd 1.5 Ba CoFeMnO 9−δ , enriched with oxygen defects shows high activity and durability as a bifunctional electrocatalyst.

Development of oxygen evolution reaction (OER) catalysts with reduced precious metal content while enhancing catalytic performance has been pivotal importance in cost‐effective design acid polymer electrolyte membrane water electrolyzers. Hollow multimetallic nanostructures well‐defined facets are ideally suited for saving the usage expensive metals as well boosting performances; however, Ir‐based hollow nanocatalysts have rarely reported. Here, a very simple synthetic scheme is reported...

We report on reduced graphene oxide (rGO)/mesoporous (mp)-TiO2 nanocomposite based mesostructured perovskite solar cells that show an improved electron transport property owing to the interfacial resistance. The amount of rGO added TiO2 nanoparticles layer was optimized, and their impacts film resistivity, diffusion, recombination time, photovoltaic performance were investigated. rGO/mp-TiO2 reduces resistance when compared mp-TiO2 film, hence, it improves charge collection efficiency. This...

Abstract A facile, scalable route to new nanocomposites that are based on carbon nanotubes/heteroatom‐doped (CNT/HDC) core–sheath nanostructures is reported. These were prepared by the adsorption of heteroatom‐containing ionic liquids walls CNTs, followed carbonization. The design CNT/HDC composite allows for combining electrical conductivity CNTs with catalytic activity HDC sheath layers. highly active electrocatalysts oxygen reduction reaction and displayed one best performances among...

Iron and nitrogen codoped carbons (Fe-N/C) have emerged as promising nonprecious metal catalysts for the oxygen reduction reaction (ORR). While Fe-Nx sites been widely considered active species Fe-N/C catalysts, very recently, iron and/or carbide encased with carbon shells (Fe-Fe3C@C) has suggested a new site ORR. However, most of synthetic routes to involve high-temperature pyrolysis, which unavoidably yield both Fe-Fe3C@C species, hampering identification exclusive role each species....

Ice-templated self-assembly is used for the integration of 2D graphene sheets into hierarchically porous nanoscroll networks.

Metal sulfide-based nanostructured materials have emerged as promising catalysts for hydrogen evolution reaction (HER), and significant progress has been achieved in enhancing their activity durability the HER. The understanding of nanoscale size-dependent catalytic activities can suggest critical information regarding reactivity, providing scientific basis design advanced catalysts. However, size effects metal HER not yet established fully, due to synthetic difficulty precisely...

Developments of high-performance cost-effective electrocatalyts that can replace Pt catalysts have been a central theme in polymer electrolyte membrane fuel cells (PEMFCs) and direct methanol (DMFCs). In this direction, nitrogen-doped carbon nanostructures free metallic components attracted particular attention. Here we show directing graphitic nitride frameworks into mesoporous architecture generate highly promising metal-free electrocatalyst for an oxygen reduction reaction (ORR) acidic...

The rational design of highly efficient electrocatalysts for the hydrogen evolution reaction (HER) is prime importance establishing renewable and sustainable energy systems. alkaline HER particularly challenging as it involves a two-step water dissociation recombination, which platinum-based binary catalysts have shown promising activity. In this work, we synthesized high performance platinum-nickel-cobalt alloy nanocatalysts through simple synthetic route. This ternary nanostructure with...

The development of active and stable non-precious-metal electrocatalysts for energy conversion reactions involving hydrogen oxygen has been pivotal importance realizing a clean-energy-based society. As class electrocatalysts, cobalt- nitrogen-codoped carbon (Co–N/C) catalysts have shown promising activity the evolution reaction (HER). further advancement Co–N/C is, however, hindered by poor understanding their sites; typical preparation involves high-temperature pyrolysis, yielding with...

Bifunctional oxygen electrocatalysts play a vital role in important energy conversion and storage devices. Cost-effective, abundant, active Co-based materials have emerged as promising bifunctional for which identifying catalytically structures under reaction conditions unraveling the structure–activity relationships are of critical importance. Here, we report size-dependent (3–10 nm) structure catalytic activity cobalt oxide nanoparticle (CoOx NP) catalysts evolution (OER) reduction (ORR)....

Efficient and cost‐effective bifunctional electrocatalysts for oxygen evolution reaction (OER) reduction (ORR) are of vital importance in energy conversion storage devices. Despite the recent progress electrocatalysts, their unbalanced insufficient OER ORR activities has continued to pose challenges practical application such The design highly integrated, high‐performance, composed graphitic nanoshells embedded mesoporous carbon (GNS/MC) is reported. GNS/MC exhibits very high electrode...

Iron- and nitrogen-codoped carbon (Fe–N/C) catalysts have emerged as promising alternatives to Pt-based for the oxygen reduction reaction (ORR) owing their prominent ORR activity among nonprecious metal (NPMCs). This high originates from atomically dispersed Fe coordinated with nitrogen atoms (Fe–Nx site). However, rational design of Fe–N/C abundant Fe–Nx active sites remains a challenge. In this work, we demonstrate that silica-coating-mediated synthetic strategy enables preparation...

Atomically dispersed nickel sites complexed on nitrogen-doped carbon (Ni–N/C) have demonstrated considerable activity for the selective electrochemical dioxide reduction reaction (CO2RR) to CO. However, high-temperature treatment typically involved during activation of Ni–N/C catalysts makes origin high elusive. In this work, Ni(II) phthalocyanine molecules grafted nanotube (NiPc/CNT) and heat-treated NiPc/CNT (H-NiPc/CNT) are exploited as model investigate impact thermal structure active...

Controlled thermal conversion of Mn-based metal–organic frameworks yielded a series nanoporous manganese oxides with continuously tuned oxidation states.

The preparation of size- and shape-controlled nanoparticles has enabled the understanding important nanoscale catalytic phenomena, resulting in design advanced catalysts with enhanced activities selectivities. Metal phosphides have recently emerged as a promising class non-precious metal for hydrogen evolution reaction (HER), which is cornerstone clean environmentally benign production. Although significant progress been made phosphide catalysts, impact shape not yet explored. Herein, we...

Lignin is a major component of lignocellulosic biomass. Although it highly recalcitrant to break down, very abundant natural source valuable aromatic carbons. Thus, the effective valorisation lignin crucial for realising sustainable biorefinery chain. Here, we report compartmented photo-electro-biochemical system unassisted, selective, and stable valorisation, in which TiO2 photocatalyst, an atomically dispersed Co-based electrocatalyst, biocatalyst (lignin peroxidase isozyme H8, horseradish...