Abstract: A high-side transistor includes N (N represents an integer of two or more) high-side transistor units electrically arranged in parallel between a high-side power supply line and an output terminal for the corresponding phase. A low-side transistor includes N low-side transistor units electrically arranged in parallel between a low-side power supply line and an output terminal for the corresponding phase. A snubber circuit is provided for each pair of a high-side transistor unit and a corresponding low-side transistor unit. The high-side transistor, the low-side transistor, and the N snubber circuits are mounted on a metal base substrate.

Abstract: To provide an electrode catalyst for fuel cells, which is obtained efficiently by a simple process, without using a silica template, unlike in the conventional process, which is relatively large in mesopore diameter (5 nm or more), which enables catalyst particles deposited stably in the mesopores, and which can readily develop a highly triple-phase interface state. Such an electrode catalyst for a fuel cell is constituted with: a mesoporous carbon support obtained by heating and baking for carbonization a mixture of a surfactant and carbon precursors; and catalyst particles carried by the support. Further, it is possible to obtain a fuel cell, which has: a fuel electrode; an air electrode; and an electrolyte membrane interposed between the electrodes, in which at least one of the fuel electrode and the air electrode contains the electrode catalyst.

Abstract: A self-standing mesoporous carbon membrane which is obtainable by combining the following steps and has an ordered mesoporous structure in which mesopores are oriented in a direction perpendicular to a surface plane: (i) applying a mixture of a surfactant and a carbon precursor composed of a thermosetting resin precursor and a crosslinking agent therefor, to the surface of a substrate, to form a membrane of the mixture; (ii) drying the membrane at 15 to 30° C. under the atmospheric pressure; (iii) heating the dried membrane, to cause polymerization of the carbon precursor; (iv) baking to carbonize the polymerized membrane; (v) peeling the baked and carbonized membrane from the substrate; and (vi) baking further to carbonize the peeled carbon membrane that is self-standing.