Electrode catalyst layer for carbon dioxide electrolysis cell, electrolysis cell and carbon dioxide electrolysis apparatus comprising the same

An electrolysis cell, comprising:

• an anode unit comprising an anode suitable to oxidize water or hydroxy ions into oxygen, and an anode solution-flow path through which an anode solution is supplied to the anode;
• a cathode unit comprising a cathode comprising a catalyst layer and being suitable to reduce carbon dioxide into a carbon compound, and a gas-flow path through which carbon dioxide is supplied to the cathode;
• and
• a separator arranged to separate the anode unit and the cathode unit from each other,
• wherein the catalyst layer comprises a carbonaceous catalyst carrier and a metallic catalyst loaded on the carbonaceous catalyst carrier,
• wherein the metallic catalyst comprises Au, Ag, Cu, Pt, Pd, Ni, Co, Fe, Mn, Ti, Zn, and/or Ga, as a metal,
• wherein the catalyst layer comprises primary particles of the carbonaceous catalyst carriers which are aggregated to form secondary particles,
• the catalyst layer has a porous structure comprising pores of a diameter less than 5 μm inside and among the primary particles and pores of 5 to 200 μm among the secondary particles, diameters measured by a mercury injection method,
• wherein a volume of the pores having a diameter of 5 to 200 μm among the secondary particles per weight of the catalyst layer is in a range of from 3.0 to 10 mL/g, and
• wherein the pore-diameter distribution measured by a mercury injection method shows the highest peak of frequency distribution in the diameter range of from greater than 10 μm to less than 50 μm, provided that the diameter and the logarithmic differential pore volume are plotted on the horizontal and vertical axes, respectively.

An electrolysis cell, comprising:

• an anode unit comprising an anode suitable to oxidize water or hydroxy ions into oxygen, and an anode solution-flow path through which an anode solution is supplied to the anode;
• a cathode unit comprising a cathode comprising a catalyst layer and being suitable to reduce carbon dioxide into a carbon compound, a cathode solution-flow path through which a cathode solution is supplied to the cathode, and a gas-flow path through which carbon dioxide is supplied to the cathode;
• and
• a separator arranged to separate the anode unit and the cathode unit from each other;
• provided that
• the anode is so placed between the separator and the anode solution-flow path as to be in contact with them,
• wherein the catalyst layer comprises primary particles of the carbonaceous catalyst carriers which are aggregated to form secondary particles,
• the catalyst layer has a porous structure comprising pores of a diameter less than 5 μm inside and among the primary particles and pores of 5 to 200 μm among the secondary particles, diameters measured by a mercury injection method,
• wherein a volume of the pores having a diameter of 5 to 200 μm among the secondary particles per weight of the catalyst layer is in a range of from 3.0 to 10 mL/g, and
• wherein the pore-diameter distribution measured by a mercury injection method shows the highest peak of frequency distribution in the diameter range of from greater than 10 μm to less than 50 μm, provided that the diameter and the logarithmic differential pore volume are plotted on the horizontal and vertical axes, respectively.