北海道大学 · 재료과학
Kei Murakoshi 교수의 연구실은 나노소재 기반의 에너지 변환 및 저장 장치 개발에 초점을 맞추고 있습니다. 특히 산소 환원 반응(ORR)과 산소 발생 반응(OER)을 위한 고성능 비백금 계 촉매, 나노입자 기반 태양전지, 그리고 질소 및 불소 도핑을 통한 탄소 기반 촉매의 설계에 대한 연구를 진행하고 있습니다. 다양한 나노구조물(예: 탄소나노튜브, 그래핀, 카드뮴 sulfide 나노결정체)의 표면 기능화 및 크기 제어를 통해 반응성과 안정성을 극대화하는 데 주력하고 있습니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
A highly active iron–nitrogen‐doped carbon nanotube catalyst for the oxygen reduction reaction (ORR) is produced by employing vertically aligned carbon nanotubes (VA‐CNT) with a high specific surface area and iron(II) phthalocyanine (FePc) molecules. Pyrolyzing the composite easily transforms the adsorbed FePc molecules into a large number of iron coordinated nitrogen functionalized nanographene (Fe–N–C) structures, which serve as ORR active sites on the individual VA‐CNT surfaces. The catalyst
Nitrogen-doped graphene materials with abundant pyridinic and quaternary nitrogen species were selectively synthesized by thermal surface polymerization of nitrogen-containing aromatic molecules. Catalytic studies revealed that the oxygen reduction by nitrogen-doped graphene, containing pyridinic and quaternary nitrogen species, proceeds via a four- and two-electron reduction pathway, respectively, in alkali-based solutions.
Abstract Solid type dye-sensitized solar cell was fabricated using photodepositing polypyrrole onto the surface of porous TiO2 electrode anchored by photosensitizing molecules of a ruthenium complex. Polypyrrole in the porous medium successfully works as hole transport layer connecting the sensitizer dye molecules to a counter electrode. Doping density of the polypyrrole conducting layer was optimized to improve the efficiency of the system.
Hexagonal CdS nanocrystallites have been easily prepared by reacting Cd2+ and S2- (H2S or Na2S) in N,N-dimethylformamide (DMF) without adding any surface stabilizers. The mean diameter of the nanocrystallites can be rigorously controlled over the range 1.8–4.2 nm with keeping the hexagonal crystalline structure by varying the sulfur source (H2S and Na2S) and by regulating the preparation temperature. Use of Na2S as a sulfur source produces smaller CdS nanocrystallites than use of H2S. The size c
Pentafluorothiophenol, thiophenol, 1-decanethiol, 1-hexanethiol, benzoic acid and cyanoacetic acid, which are confirmed to bind to the surface of ZnS nanocrystallites, induce phase transition of ZnS nanocrystallites from the hexagonal to the cubic phase, with retention of the crystalline size of 3 nm at ambient temperature and pressure.
Metal-free carbonaceous catalysts have potential applications for oxygen evolution reaction (OER) devices because of their low-cost and abundant supply. We report that fluorine-doped carbon black is an active catalyst for OER. Fluorine-doped carbon black (F-KB) is simply synthesized by the pyrolysis of KETJENBLACK (KB) as carbon substrate with Nafion as fluorine precursor. As a result, the OER activity of F-KB is significantly higher than that of pristine KB in alkaline media. The OER catalytic
The effect of illumination on the agglomeration of surface-modified gold nanoparticles both in solution and on gold (111) surfaces is investigated here. It is shown that illumination induces additional interparticle interactions, which can be controlled by changing the illumination wavelength. The Figure shows linear arrays of gold nanoparticles formed on a gold surface upon illumination at 830 nm.