Metal-loaded catalyst, electrode, and battery

A metal-supported catalyst, comprising:

• a carbon carrier;
• and
• catalyst metal particles supported on the carbon carrier, the particles each containing a noble metal alloy,
• wherein a ratio of a weight of a noble metal to a weight of the metal-supported catalyst is 35 wt % or more,
• wherein the metal-supported catalyst has a BET specific surface area of 350 (m2/g-carbon carrier) or more, and
• wherein the metal-supported catalyst has
• the following characteristic (a1) and/or (a2):
• (a1) a ratio of an intensity of a 2D band having a peak top in a vicinity of a Raman shift of 2,680 cm−1 to an intensity of a G band having a peak top in a vicinity of a Raman shift of 1,600 cm−1 in a Raman spectrum obtained by Raman spectroscopy is 0.20 or more and 1.00 or less;
• and
• (a2) a half width at half maximum of a D band having a peak top in a vicinity of a Raman shift of 1,340 cm−1 in the Raman spectrum obtained by the Raman spectroscopy is 41.0 cm−1 or less, and
• the following characteristic (b1) and/or (b2):
• (b1) an alloy composition nonuniformity, which is calculated from the following equation (I), is 0.55 or less:
• alloy
• ⁢
• composition
• ⁢
• nonuniformity
• =
• (
• 1
• -
• theoretical
• ⁢
• lattice
• ⁢
• constant
• /
• measured
• ⁢
• lattice
• ⁢
• constant
• )
• ×
• 100
• (
• I
• )
• in the equation (I), the theoretical lattice constant and the measured lattice constant are a theoretical lattice constant and a measured lattice constant of the noble metal alloy, respectively;
• and
• (b2) a half-maximum asymmetry and a ¼-maximum asymmetry, which are respectively calculated from the following equation (II) and equation (III), are each 0.55 or less:
• half
• -
• maximum
• ⁢
• asymmetry
• =
• ❘
• "\[LeftBracketingBar]"
• (
• D
• m
• -
• D
• Lh
• )
• -
• (
• D
• Hh
• -
• D
• m
• )
• ❘
• "\[RightBracketingBar]"
• (
• II
• )
• 1
• /
• 4
• -
• maximum
• ⁢
• asymmetry
• =
• ❘
• "\[LeftBracketingBar]"
• (
• D
• m
• -
• D
• Lq
• )
• -
• (
• D
• Hq
• -
• D
• m
• )
• ❘
• "\[RightBracketingBar]"
• (
• III
• )
• in the equation (II) and the equation (III), Dm represents a value of a diffraction angle 2θ at which a diffraction line exhibits a maximum intensity in a range of the diffraction angle 2θ in which a diffraction peak of a (111) plane of the noble metal alloy appears in an X-ray diffraction pattern obtained by powder X-ray diffraction, DU represents a value of a smallest diffraction angle 2θ among diffraction angles 2θ at which the diffraction line exhibits an intensity equal to one half of the maximum intensity in the range, DHh represents a value of a largest diffraction angle 2θ among the diffraction angles 2θ at which the diffraction line exhibits the intensity equal to one half of the maximum intensity in the range, DLq represents a value of a smallest diffraction angle 2θ among diffraction angles 2θ at which the diffraction line exhibits an intensity equal to one quarter of the maximum intensity in the range, and DHq represents a value of a largest diffraction angle 2θ among the diffraction angles 2θ at which the diffraction line exhibits the intensity equal to one quarter of the maximum intensity in the range.