N.e. Chemcat Corporation

National Institute of Advanced Industrial Science and Technology

Advanced Industrial Science and Technology

Tomoteru Mizusaki

Kiyotaka Nagamori

Yoko Nakamura

Yasuhiro Seki

Hiroshi Igarashi

Takuya Tsubaki

Yukio Takagi

Norihisa Fukaya

Junchul Choi

Hiroyuki Yasuda

Kazuhiko Sato

Shunya Onozawa

Satoshi Aoki

Yoshiyuki Wada

Kazuhiro Matsumoto

Hiroki Shiina

The present invention provides an electrode catalyst which has excellent catalytic activity, and which can contribute to reducing the cost of a polymer electrolyte fuel cell (PEFC). According to the present invention, an electrode catalyst includes a hollow carrier including nanopores having a pore size of 1 to 20 nm, and a plurality of catalyst particles. The catalyst particles are supported both inside and outside the nanopores of the carrier, and comprise (zero-valent) Pt, and when a particle size distribution analysis of the catalyst particles is carried out using a three-dimensional reconstructed image obtained by electron beam tomography measurement employing STEM, the conditions of formula (S1): 100×(N10/N20)≤8.0 are satisfied (in the formula, N10 is the number of noble metal particles not in contact with a pore having a pore size of 1 nm or more, and N20 is the number of catalyst particles supported inside the nanopores of the carrier).

Electrode catalyst, composition for forming gas diffusion electrode, gas diffusion electrode, membrane electrode assembly, and fuel cell stack

It is an object of the present invention to provide a catalyst for a cross-coupling reaction in which an organometallic complex is sufficiently immobilized on a carrier and an object product can be easily obtained in a high yield and in a relatively short reaction time with a relatively small amount of use. The catalyst for a cross-coupling reaction of the present invention has a carrier part composed of a synthetic resin and an organometallic complex part immobilized on the carrier part by chemical bonding, and has a structure represented by formula (P1), wherein in (P1) R, Rmay be the same or different, and is a substituent such as a hydrogen atom. R, R, R, R, R, Rmay be the same or different and are substituents, such as a hydrogen. X represents a halogen atom, and Rrepresents a substituent having 3 to 20 carbon atoms with a π bond. RS1 represents the main chain of the synthetic resin precursors having —CHOH group at their end.

Cross-coupling reaction catalyst

Provide an electrode catalyst with excellent catalytic activity that can contribute to cost reduction of PEFC. The electrode catalyst includes a hollow carbon carrier with mesopores with a pore size of 2 to 50 nm and a catalyst particle supported on the carrier. The catalyst particle is supported on both inside and outside the mesopores of the carrier, and have a core portion formed on the carrier and a shell portion covering at least a part of the surface of the core portion. Pd is included in the core portion, and Pt is included in the shell portion, and when the analysis of the particle size distribution of the catalyst particles using the three dimensional reconstructed image obtained by electron beam tomography (electron tomography) measurement using an STEM is performed, the ratio of the catalyst particles supported inside the mesopore is 50% or more.

Electrode catalyst, composition for forming gas diffusion electrode, gas diffusion electrode, membrane electrode assembly and fuel cell stack

An organometallic complex catalyst that makes it possible to obtain a higher yield of a desired product than conventional catalysts in a cross-coupling reaction. The organometallic complex catalyst has a structure represented by formula (1) and is for use in a cross-coupling reaction. In formula (1), M is the coordination center and represents a metal atom such as Pd or an ion thereof. R1, R2, and R3 may be the same or different and are a substituent such as a hydrogen atom. R4, R5, R6, and R7 may be the same or different and are a substituent such as a hydrogen atom. X represents a halogen atom. R8 represents a substituent that has a &#x3c0; bond and 3-20 carbon atoms. With regard to the electron-donating properties of R1-R7 with respect to the coordination center M of the ligand containing R1-R7 that is indicated in formula (2), R1-R7 are arranged in combination such that the TEP value obtained from infrared spectroscopy shifts toward the low frequency side compared to the TEP value of the ligand of formula (2-1). 

Organometallic complex catalyst

An organometallic complex catalyst is disclosed for use in a cross-coupling reaction. In formula (1), M is the coordination center and represents a metal atom such as Pd or an ion thereof. R, R, and Rmay be the same or different and are a substituent such as a hydrogen atom. R, R, R, and Rmay be the same or different and are a substituent such as a hydrogen atom. X represents a halogen atom. Rrepresents a substituent that has a &#x3c0; bond and 3-20 carbon atoms. With regard to the electron-donating properties of R-Rwith respect to the coordination center M of the ligand containing R-Rthat is indicated in formula (2), R-Rare arranged in combination such that the TEP value obtained from infrared spectroscopy shifts toward the high frequency side compared to the TEP value of the ligand of formula (2-1). 

Provided is an electrode catalyst that can exhibit sufficient performance, is suitable for mass production, and is suitable for reducing production costs, even when containing a relatively high concentration of chlorine. The electrode catalyst has a core-shell structure including a support; a core part that is formed on the support; and a shell part that is formed so as to cover at least one portion of the surface of the core part. A concentration of bromine (Br) species of the electrode catalyst as measured by X-ray fluorescence (XRF) spectroscopy is 500 ppm or less, and a concentration of chlorine (Cl) species of the electrode catalyst as measured by X-ray fluorescence (XRF) spectroscopy is 8,500 ppm or less.

Electrode catalyst, composition for forming gas diffusion electrode, gas diffusion electrode, membrane-electrode assembly, and fuel cell stack

To provide electrode catalyst (core-shell catalyst) having an excellent catalyst activity which contributes to lower the cost of the PEFC. The electrode catalyst has catalyst particles supported an a support. The catalyst particle has a core part containing simple Pd and a shell part containing simple Pt. A percentage R(atom %) of the carbon of the support and a percentage R(atom %) of the simple Pd in an analytical region near a surface measured by X-ray photoelectron spectroscopy (XPS) satisfy the conditions of the following equation (1): 2.15&#x2264;[100&#xd7;R/(R+R)].

Electrode catalyst, composition for forming gas diffusion electrode, gas diffusion electrode, membrane-electrode assembly, fuel cell stack, method for producing electrode catalyst, and composite particle

Provided is an electrode catalyst in which the contents of chlorine (Cl) species and bromine (Br) species are reduced to a predetermined level or lower, capable of exhibiting sufficient catalyst performance. The electrode catalyst has a core-shell structure including a support, a core part formed on the support and a shell part formed to cover at least a part of the surface of the core part. A concentration of bromine (Br) species of the electrode catalyst as measured by X-ray fluorescence (XRF) spectroscopy is 400 ppm or less, and a concentration of chlorine (Cl) species of the electrode catalyst as measured by X-ray fluorescence (XRF) spectroscopy is 900 ppm or less.

Electrode catalyst, gas diffusion electrode-forming composition, gas diffusion electrode, membrane electrode assembly, and fuel cell stack

To provide electrode catalyst which has the catalyst activity and durability at a practically durable level and contributes to lowering of the cost in comparison with the conventional Pt/C catalyst. The electrode catalyst has a support and catalyst particles supported on the support. The catalyst particle has the core part, the first shell part formed on the core part, and the second shell part formed on the first shell part. The core part contains W compound including at least W carbide, the first shell part contains simple Pd, and the second shell part contains simple Pt.

Electrode catalyst, composition for forming gas diffusion electrode, gas diffusion elelctrode, membrane-electrode assembly, and fuel cell stack

Provided is an electrode catalyst production method capable of obtaining, through an easy operation, an electrode catalyst whose chlorine (Cl) species content has been reliably and sufficiently reduced, even when using as an electrode catalyst raw material an electrode catalyst precursor containing a high concentration of chlorine. The method is to produce an electrode catalyst having a core-shell structure including a support, a core part formed on the support and a shell part formed to cover at least a part of a surface of the core part. The method includes a first step (1) of retaining a liquid containing ultrapure water, a reductant such as a hydrogen-containing gas and an electrode catalyst precursor under at least one stage of a predetermined temperature for a predetermined retention time, such electrode catalyst precursor being produced using a material containing chlorine (Cl) species, and exhibiting a chlorine (Cl) species concentration not lower than a predetermined first chlorine (Cl) species concentration when measured by X-ray fluorescence (XRF) spectroscopy.

Production method of electrode catalyst, electrode catalyst, composition for forming gas diffusion electrode, gas diffusion electrode, membrane-electrode assembly (MEA), and fuel cell stack

Provided is an electrode catalyst that can exhibit sufficient performance, is suitable for mass production, and is suitable for reducing production costs, even when containing a relatively high concentration of chlorine. The electrode catalyst has a core-shell structure including a support; a core part that is formed on the support; and a shell part that is formed so as to cover at least one portion of the surface of the core part. The electrode catalyst concurrently fulfills conditions expressed by the following formulae (1) and (2): (X1/M)&#x2266;1.2 . . . (1) (X2/M)&#x2266;47.0 . . . (2) (in the formula (1) and the formula (2), M represents an amount of substance (number of atoms) of one or more constituent metal elements of the shell part, X1 represents an amount of substance (number of atoms) of bromine (Br), and X2 represents an amount of substance (number of atoms) of chlorine (Cl)).

Provided is a production method of an electrode catalyst that can reduce the content of chlorine species reliably and sufficiently through a simple operation, even when using an electrode catalyst precursor containing a high concentration of chlorine (Cl) species as a raw material of the electrode catalyst. The production method of the electrode catalyst has a core-shell structure including a core part formed on a support and a shell part formed to cover at least a part of a surface of the core part. The production method includes a first step (1) of preparing a first liquid with an electrode catalyst precursor (I) being dispersed in ultrapure water by adding the electrode catalyst precursor (I) to the ultrapure water, the electrode catalyst precursor (I) being produced using a material containing chlorine (Cl) species, and exhibiting a chlorine (Cl) species concentration not lower than a first chlorine (Cl) species concentration when measured by X-ray fluorescence (XRF) spectroscopy; and a second step (2) of preparing a second liquid by dispersing an electrode catalyst precursor (II), the electrode catalyst precursor (II) being obtained by filtrating and washing the electrode catalyst precursor (I) contained in the first liquid with ultrapure water, and then performing washing until an electric conductivity &#x3c1; of a filtrate has become a first value or lower.

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Bando, Japan

Tomoteru Mizusaki