Young Jin

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

The electrochemical reduction of CO2 stores intermittent renewable energy in valuable raw materials, such as chemicals and transportation fuels, while minimizing carbon emissions and promoting carbon-neutral cycles. Recent technoeconomic reports suggested economically feasible target products of CO2 electroreduction and the relative influence of key performance parameters such as faradaic efficiency (FE), current density, and overpotential in the practical industrial-scale applications. Furtherm

A highly efficient, metal-free carbon nanocatalyst is presented that possesses abundant active, oxygenated graphitic edge sites. The edge site-rich nanocarbon catalyst exhibits about 28 times higher activity for H₂ O₂ production than a basal plane-rich carbon nanotube with a H₂ O₂ selectivity over 90 %. The oxidative treatment further promotes the H₂ O₂ generation activity to reach close to the thermodynamic limit. The optimized n

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

A facile, scalable route to new nanocomposites that are based on carbon nanotubes/heteroatom-doped carbon (CNT/HDC) core-sheath nanostructures is reported. These nanostructures were prepared by the adsorption of heteroatom-containing ionic liquids on the walls of CNTs, followed by carbonization. The design of the CNT/HDC composite allows for combining the electrical conductivity of the CNTs with the catalytic activity of the heteroatom-containing HDC sheath layers. The CNT/HDC nanostructures are

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

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

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

H₂O₂ electrosynthesis is an emerging clean chemical technology, whose efficiency critically depends on the activity and selectivity of electrocatalysts for two-electron oxygen reduction reaction (2e^- ORR). Here, we demonstrate that 2e^- ORR activity of oxygen-doped carbons, which have been one of the most promising catalysts for this reaction, can be substantially influenced by the types and concentrations of cations in electrolytes. Heat-treated carbon

The electrosynthesis of H2O2 via a two-electron pathway oxygen reduction reaction (2e− ORR) has emerged as a promising way of carbon-free and on-site production of H2O2. Active and selective electrocatalysts for the 2e− ORR are essential for achieving high O2-to-H2O2 conversion efficiency. In this review, we present the recent progress in the development of 2e− ORR electrocatalysts including Pt-group-metal (PGM) and non-PGM atomically dispersed catalysts and metal-free heteroatom-doped carbons.

Electrochemical production of H2O2 via a 2-electron oxygen reduction reaction (2e– ORR) provides a clean alternative to the traditional industrial process. H2O2 electrosynthesis in noncaustic neutral electrolytes is desirable for broader applications; however, it requires larger overpotentials compared to those in alkaline electrolytes where a high 2e– ORR activity can be achieved even with metal-free carbon electrocatalysts. Although ceria has been widely adopted as a catalytic promoter in ther

Active and nonprecious-metal bifunctional electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are vital components of clean energy conversion devices such as regenerative fuel cells and rechargeable metal-air batteries. Porous manganese oxides (MnO_<i>x</i>) are promising electrocatalyst candidates because of their high surface area and the abundance of Mn. MnO_<i>x</i> catalysts exhibit various oxidation states and crystal structures,