Masahiko Hara

Photocatalytic decomposition of water into H2 and O2 on Cu2O under visible light irradiation is investigated; the photocatalytic water splitting on Cu2O powder proceeds without any noticeable decrease in the activity for more than 1900 h.

Incomplete carbonization of sulfoaromatic hydrocarbons results in a carbon material that consists of small polycyclic aromatic carbon sheets with attached SO3H groups (see picture). This insoluble solid acid exhibits remarkably high activity in the formation of ethyl acetate, the hydrolysis of cyclohexyl acetate, and the hydration of 2,3-dimethyl-2-butene.

Aerobic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) as a bioplastics monomer is efficiently promoted by a simple system based on a nonprecious-metal catalyst of MnO₂ and NaHCO₃. Kinetic studies indicate that the oxidation of 5-formyl-2-furancarboxylic acid (FFCA) to FDCA is the slowest step for the aerobic oxidation of HMF to FDCA over activated MnO₂. We demonstrate through combined computational and experimental studies that H

The efficient reduction of atmospheric nitrogen to ammonia under low pressure and temperature conditions has been a challenge in meeting the rapidly increasing demand for fertilizers and hydrogen storage. Here, we report that Ca₂N:e^-, a two-dimensional electride, combined with ruthenium nanoparticles (Ru/Ca₂N:e^-) exhibits efficient and stable catalytic activity down to 200 °C. This catalytic performance is due to [Ca₂N]⁺·e<sub>1-<

Amorphous carbon bearing sulfonic acid groups, a new type of solid Brønsted acid catalyst, was investigated for potential application to environmentally benign biodiesel production and cellulose saccharification. The carbon material exhibits much higher catalytic performance for the esterification of higher fatty acids, transesterification of triglycerides and the hydrolysis of cellulose than conventional solid acid catalysts.

A buffered tris(2,2‘-bipyridyl)ruthenium complex-colloidal IrO2 system was studied as a photocatalyst for the production of O2 from water. Phosphate buffer, which has historically been used to control the pH in this system, accelerates the decomposition of the photosensitizer and inhibits O2 evolution, whereas sodium hexafluorosilicate (Na2SiF6)−base solutions are ideal buffers for the reaction. Na2SiF6-containing buffers poise the solution under visible light irradiation at ca. pH 5, preventing

The photocatalytic cleavage of water has become of increasing interest in recent years for the manufacture of hydrogen, a clean and renewable energy carrier. The production of H2 using heterogeneous photocatalysts is reviewed in this feature article. Particulate or electrode heterogeneous catalysts under light irradiation can successively reduce H+ into H2 and oxidize water to produce O2, achieving cleavage of water (H2O → H2 + 1/2O2).

The artificial mass production of ammonia has supported the increase in human population and modern civilization for over 100 years. However, more efficient ammonia production is now a significant concern for society. Here we show that Ru-loaded C12A7:e– electride derived from 12CaO·7Al2O3 (C12A7:O2–) acts as an efficient and stable catalyst for ammonia synthesis. Ammonia synthesis over Ru nanoparticles-loaded C12A7:e– (Ru/C12A7:e–) is distinct from other conventional catalysts in both mechanism

A low-temperature ammonia synthesis process is required for on-site synthesis. Barium-doped calcium amide (Ba-Ca(NH₂ )₂ ) enhances the efficacy of ammonia synthesis mediated by Ru and Co by 2 orders of magnitude more than that of a conventional Ru catalyst at temperatures below 300 °C. Furthermore, the presented catalysts are superior to the wüstite-based Fe catalyst, which is known as a highly active industrial catalyst at low temperatures and pressures. Nanosized Ru-Ba co

H2 evolution on TaON photocatalyst under visible light irradiation (420 nm < or = lambda < or = 500 nm) in an aqueous methanol solution is found to be remarkably enhanced by adding Ru as a noble-metal co-catalyst.

A simple non-precious-metal catalyst system based on costeffective and ubiquitously available MnO₂ , NaHCO₃ , and molecular oxygen was used to convert 5-hydroxymethylfurfural (HMF) to 2,5-difurandicarboxylic acid (FDCA) as a bioplastics precursor in 91 % yield. The MnO₂ catalyst could be recovered by simple filtration and reused several times. The present system was also applicable to the aerobic oxidation of other biomass-derived substrates and the gram-scale ox