Mesoporous carbon, electrode catalyst for fuel cell, and catalyst layer

Mesoporous carbon comprising:

• a linked structure in which carbon particles are linked, wherein
• the carbon particles have primary pores and are primary particles,
• an average entrance diameter of the primary pores is 2.0 nm or more and 3.0 nm or less, and
• an average constriction diameter of the primary pores is 1.6 nm or more and 2.4 nm or less, the average entrance diameter being an average of circle equivalent diameters at entrances of the primary pores that are open to surfaces of the carbon particles, as measured by three-dimensional transmission electron microscope image analysis, and the average constriction diameter being an average of circle equivalent diameters of constrictions of the primary pores inside the carbon particles, as measured by the three-dimensional transmission electron microscope image analysis;
• wherein the mesoporous carbon exhibits a high temperature and low humidity voltage of 570 mV or more.