Theoretical Study on Solubility from Pt Electrocatalyst and Reactivity in Electrolyte Environment of Pt Complex in PEFC

Table 9

Reaction energy for Pt(IV) complexes with various dielectric constants. Unit is kJ/mol.

	5.0	20.0	61.0
Proton addition reaction
(𝟐) [Pt(H2O)5(OH)]^3+ + H3O^+ → (𝟏) [Pt(H2O)6]^4+ + H2O	396.3	182.5	141.5
(𝟑) [Pt(H2O)4(OH)2]^2+ + H3O^+ → (𝟐) [Pt(H2O)5(OH)]^3+ + H2O	216.4	105.5	63.6
(𝟒) [Pt(H2O)3(OH)3]^+ + H3O^+ → (𝟑) [Pt(H2O)4(OH)2]^2+ + H2O	63.6	18.0	−1.3
(𝟓) [Pt(H2O)2(OH)4] + H3O^+ → (𝟒) [Pt(H2O)3(OH)3]^+ + H2O	−120.5	−89.1	−74.1
(𝟏𝟎) [Pt(H2O)4(OH)(CF3SO3)]^2+ + H3O^+ → (𝟔) [Pt(H2O)5(CF3SO3)]^3+ + H2O	222.2	137.7	94.6
(𝟏𝟏) [Pt(H2O)3(OH)2(CF3SO3)]^+ + H3O^+ → (𝟏𝟎) [Pt(H2O)4(OH)(CF3SO3)]^2+ + H2O	57.3	8.0	0.0
(𝟏𝟐) [Pt(H2O)2(OH)3(CF3SO3)] + H3O^+ → (𝟏𝟏) [Pt(H2O)3(OH)2(CF3SO3)]^+ + H2O	7.1	28.0	35.6
(𝟏𝟑) [Pt(H2O)3(OH)(CF3SO3)2]^+ + H3O^+ → (𝟕) [Pt(H2O)4(CF3SO3)2]^2+ + H2O	117.2	85.8	58.2
(𝟏𝟒) [Pt(H2O)2(OH)2(CF3SO3)2] + H3O^+ → (𝟏𝟑) [Pt(H2O)3(OH)(CF3SO3)2]^+ + H2O	−9.2	−0.4	13.8
(15) [Pt(H2O)2(OH)(CF3SO3)3] + H3O^+ → (8) [Pt(H2O)3(CF3SO3)3]^+ + H2O	−3.3	−53.1	−13.0
H2O/CF3SO3^− substitution reaction
(1) [Pt(H2O)6]^4+ + CF3SO3^− → (6) [Pt(H2O)5(CF3SO3)]^3+ + H2O	−502.6	−158.6	−87.5
(6) [Pt(H2O)5(CF3SO3)]^3+ + CF3SO3^− → (7) [Pt(H2O)4(CF3SO3)2]^2+ + H2O	−349.0	−135.6	−74.9
(𝟕) [Pt(H2O)4(CF3SO3)2]^2+ + CF3SO3^− → (8) [Pt(H2O)3(CF3SO3)3]^+ + H2O	−258.2	−90.8	−56.5
(8) [Pt(H2O)3(CF3SO3)3]^+ + CF3SO3^− → (9) [Pt(H2O)2(CF3SO3)4] + H2O	−127.2	−56.9	−30.6
(2) [Pt(H2O)5(OH)]^3+ + CF3SO3^− → (10) [Pt(H2O)4(OH)(CF3SO3)]^2+ + H2O	−328.9	−113.8	−40.6
(10) [Pt(H2O)4(OH)(CF3SO3)]^2+ + CF3SO3^− → (13) [Pt(H2O)3(OH)(CF3SO3)2]^+ + H2O	−244.0	−84.1	−38.5
(13) [Pt(H2O)3(OH)(CF3SO3)2]^++ CF3SO3^− → (15) [Pt(H2O)2(OH)(CF3SO3)3] + H2O	−144.4	−57.8	−11.3
(3) [Pt(H2O)4(OH)2]^2+ + CF3SO3^− → (11) [Pt(H2O)3(OH)2(CF3SO3)]^+ + H2O	−169.9	−16.7	−23.0
(11) [Pt(H2O)3(OH)2(CF3SO3)]^+ + CF3SO3^− → (14) [Pt(H2O)2(OH)2(CF3SO3)2] + H2O	−177.0	−75.7	−52.3
(4) [Pt(H2O)3(OH)3]^+ + CF3SO3^− → (12) [Pt(H2O)2(OH)3(CF3SO3)] + H2O	−113.4	−26.4	−14.2
OH^−/CF3SO3^− substitution reaction
(2) [Pt(H2O)5(OH)]^3+ + CF3SO3^− → (6) [Pt(H2O)5(CF3SO3)]^3+ + OH^−	398.0	381.7	376.2
(3) [Pt(H2O)4(OH)2]^2+ + CF3SO3^− → (10) [Pt(H2O)4(OH)(CF3SO3)]^2+ + OH^−	392.1	349.4	345.3
(4) [Pt(H2O)3(OH)3]^+ + CF3SO3^− → (11) [Pt(H2O)3(OH)2(CF3SO3)]^+ + OH^−	398.4	359.5	344.0
(5) [Pt(H2O)2(OH)4] + CF3SO3^− → (12) [Pt(H2O)2(OH)3(CF3SO3)] + OH^−	270.8	242.3	236.9
(10) [Pt(H2O)4(OH)(CF3SO3)]^2+ + CF3SO3^− → (7) [Pt(H2O)4(CF3SO3)2]^2+ + OH^−	377.9	359.9	341.9
(11) [Pt(H2O)3(OH)2(CF3SO3)]^+ + CF3SO3^− → (13) [Pt(H2O)3(OH)(CF3SO3)2]^+ + OH^−	318.1	282.1	284.2
(12) [Pt(H2O)2(OH)3(CF3SO3)] + CF3SO3^− → (14) [Pt(H2O)2(OH)2(CF3SO3)2] + OH^−	334.4	310.5	305.9
(13) [Pt(H2O)3(OH)(CF3SO3)2]^+ + CF3SO3^− → (8) [Pt(H2O)3(CF3SO3)3]^+	363.7	353.2	323.9
(14) [Pt(H2O)2(OH)2(CF3SO3)2] + CF3SO3^− → (15) [Pt(H2O)2(OH)(CF3SO3)3] + OH^−	351.1	300.1	324.8
(15) [Pt(H2O)2(OH)(CF3SO3)3] + CF3SO3^− → (9) [Pt(H2O)2(CF3SO3)4] + OH^−	380.8	354.1	304.7