Kazuhide Kamiya

Covalent triazine frameworks, which are crosslinked porous polymers with two-dimensional molecular structures, are promising materials for heterogeneous catalysts. However, the application of the frameworks as electrocatalysts has not been achieved to date because of their poor electrical conductivity. Here we report that platinum-modified covalent triazine frameworks hybridized with conductive carbon nanoparticles are successfully synthesized by introducing carbon nanoparticles during the polym

Nickel-nitrogen-modified graphene (Ni-N-Gr) is fabricated and Ni-N coordination sites on Ni-N-Gr as active centers effectively reduce CO₂ to CO. The faradaic efficiency for CO formation reaches 90% at -0.7 to -0.9 V versus RHE, and the turnover frequency for CO production comes up to ≈2700 h^-1 at -0.7 V versus RHE.

The electrochemical reduction of carbon dioxide (CO₂) has attracted considerable attention as a means of maintaining the carbon cycle. This process still suffers from poor performance, including low faradaic efficiencies and high overpotential. Herein, we attempted to use coordination number as a control parameter to improve the electrocatalytic performance of metal species that have previously been thought to have no CO₂ reduction activity. Covalent triazine frameworks (CT

We successfully developed a one-pot synthesis method of graphenes modified with iron and nitrogen. The modified graphenes functioned as an efficient electrocatalyst for the oxygen reduction reaction in acidic solutions with an onset-potential of 850 mV vs. RHE in acidic solutions.

Single-atom electrocatalysts (SACs), which comprise singly isolated metal sites supported on heterogeneous substrates, have attracted considerable recent attention as next-generation electrocatalysts for various key reactions from the viewpoint of the environment and energy. Not only electrocatalytic activity but also selectivity can be precisely tuned <i>via</i> the construction of SACs with a defined coordination structure, such as homogeneous organometallics. Covalent organic frameworks (COFs

The optimized cupric oxide nanoparticles on gas diffusion electrodes exhibited ultra-high-rate CO 2 reduction reactions to multicarbon products with a current density of 1.7 A cm −2 in neutral electrolytes.

So-called local cells resulting from the coupling of oxidation and reduction reactions on the same conductive substrate represent a well-known cause of metallic corrosion. In the present study, we attempted to demonstrate that catalytic systems based on the principle of local cell reactions can be successfully fabricated using metal-doped covalent triazine frameworks as catalytic units. A conductive substrate carrying platinum- and copper-doped covalent triazine frameworks as catalysts for the o

This work demonstrates that a single Ru atom-modified covalent triazine framework (Ru-CTF) has selectivity for the electrooxidation of benzyl alcohol in water over the oxygen evolution reaction. Additionally, Ru-CTF displayed higher stability than an immobilized Ru-organometallic complex due to the covalently cross-linked structure of CTF.

Abstract We report that graphene defects serve as active catalytic sites for the electrochemical nitrate reduction reaction (NRR). A defective graphene (without foreign elements) electrode exhibits an onset potential of 0.95 V versus Ag/AgCl for the electrochemical NRR in 5 M HNO 3 , which is 200 mV more positive than that exhibited by a platinum electrode. In addition, although the cathodic current of the platinum electrode during nitrate reduction decreases by 70 % upon the addition of 100 m M

Metal-doped covalent organic framework films are a novel polymeric platform for photoelectrocatalysts.

The electrochemical reduction of carbon dioxide (CO2) to chemical feedstocks is an attractive method for the removal of CO2 from the environment. Although copper (Cu)-based catalysts produce hydrocarbons with relatively high selectivity during CO2 electroreduction, such catalysts evolve a certain amount of H2 via proton reduction reactions. Because low-coordinated Cu sites are likely active for the competing hydrogen evolution reaction (HER), hindering such low-coordinated Cu sites by decoration

Carbon-rich materials, which contain over 90% carbon, have been mainly synthesized by the carbonization of organic compounds. However, in many cases, their original molecular and ordered structures are decomposed by the carbonization process, which results in a failure to retain their original three-dimensional (3D) ordering at the angstrom level. Recently, we successfully produced carbon-rich materials that are able to retain their 3D ordering at the angstrom level even after the calcination of

Abstract Integrated artificial photosynthesis is an approach to establish optimized systems for carbon recycling by combining high-efficiency photovoltaic and CO2 electrolysis at high productivity and selectivity. In contrast to natural photosynthesis, the integrated system aims at high energy conversion efficiency from sunlight to hydrocarbon products taking advantage of both high efficiency in photovoltaic cells and the freedom of design for individual components, while learning from the advan