Exhaust-gas aftertreatment device for an internal combustion engine, in particular for use in a motor vehicle, having an exhaust tract with at least one exhaust pipe (3, 9, 13, 15, 17) and at least one exhaust-gas aftertreatment element (7, 11), wherein the exhaust-pipe internal wall and/or the at least one exhaust-gas aftertreatment element (7, 11) have/has a vapour-sorbing material for the purpose of forming at least one exhaust-tract-side sorption element (7, 9, 11, 13, 15), wherein the at least one sorption element (7, 9, 11, 13, 15) is arranged and/or formed in a main line, through which a main exhaust-gas stream passes, of the exhaust tract, wherein the sorption of the vapour originating from the exhaust gas of the internal combustion engine by means of the vapour-sorbing material leads to a condensation of the vapour and thus to a release of heat energy, wherein a blocking device (20, 21) is provided, by means of which a supply of exhaust gas and a supply of the vapour contained in the air to a sorption region that accommodates and/or forms the at least one sorption element (7, 9, 11, 13, 15) can be blocked and enabled as a function of defined internal combustion engine operating conditions, wherein the blocking device (20, 21) has at least one blocking element arranged downstream of the sorption region for the purpose of blocking or enabling the supply of the vapour contained in the air, wherein the at least one blocking element arranged downstream is in the form of a sorption brick, and wherein said sorption brick is arranged and/or accommodated in the exhaust tract, and wherein the blocking device (20, 21) has at least one blocking element arranged upstream of the sorption region for the purpose of blocking or enabling the supply of exhaust gas, and wherein the at least one blocking element arranged upstream is in the form of a blocking valve by means of which an exhaust-gas stream through an inlet pipe that forms the inlet of the exhaust tract can be blocked or enabled. wherein the exhaust-pipe internal wall and/or the at least one exhaust-gas aftertreatment element (7, 11) have/has a vapour-sorbing material for the purpose of forming at least one exhaust-tract-side sorption element (7, 9, 11, 13, 15), wherein the at least one sorption element (7, 9, 11, 13, 15) is arranged and/or formed in a main line, through which a main exhaust-gas stream passes, of the exhaust tract, wherein the sorption of the vapour originating from the exhaust gas of the internal combustion engine by means of the vapour-sorbing material leads to a condensation of the vapour and thus to a release of heat energy, wherein a blocking device (20, 21) is provided, by means of which a supply of exhaust gas and a supply of the vapour contained in the air to a sorption region that accommodates and/or forms the at least one sorption element (7, 9, 11, 13, 15) can be blocked and enabled as a function of defined internal combustion engine operating conditions, wherein the blocking device (20, 21) has at least one blocking element arranged downstream of the sorption region for the purpose of blocking or enabling the supply of the vapour contained in the air, wherein the at least one blocking element arranged downstream is in the form of a sorption brick, and wherein said sorption brick is arranged and/or accommodated in the exhaust tract, and wherein the blocking device (20, 21) has at least one blocking element arranged upstream of the sorption region for the purpose of blocking or enabling the supply of exhaust gas, and wherein the at least one blocking element arranged upstream is in the form of a blocking valve by means of which an exhaust-gas stream through an inlet pipe that forms the inlet of the exhaust tract can be blocked or enabled.