a carrier comprising a carbon structure that has a crystallite size Lc falling within a range of 0.80 nm or more and 1.20 nm or less calculated through use of a Bragg angle of a diffraction peak f_broad at a diffraction angle 20 of 24.00±4.00 obtained by separating a diffraction peak in a vicinity of a diffraction angle 20 of 260 in an X-ray diffraction pattern obtained by powder X-ray diffraction using a CuKα ray, and that exhibits:

a carbon dioxide desorption amount in the temperature range from 650° C. to 1,200° C. of 86 μmol/g or less in a temperature programmed desorption method including measuring a carbon dioxide desorption amount in the temperature range from 25° C. to 1,200° C., and

an I_v to I_g ratio of 0.30 or more and 0.49 or less, wherein I, is a minimum intensity in a Raman spectrum obtained by Raman spectroscopy between 1,580 cm⁻¹ and 1,360 cm⁻¹, and I_g is an intensity in a vicinity of 1,580 cm⁻¹ in the Raman spectrum, and

one or more metals selected from the group consisting of platinum, ruthenium, rhodium, palladium, iridium, gold and osmium carried on the carrier.