摘要: Microelectrochemical transistors can be prepared by connecting two closely spaced (approximately 1.2 micron) Au microelectrodes (0.1 micron thick x 2.4 micron wide x 50 micron long) with anodically grown poly(3-methylthiphene). Th... 展开 Microelectrochemical transistors can be prepared by connecting two closely spaced (approximately 1.2 micron) Au microelectrodes (0.1 micron thick x 2.4 micron wide x 50 micron long) with anodically grown poly(3-methylthiphene). The amount of poly(3-methylthiophene) used involves about .0000001 to .000001 moles of monomer per sq cm. The poly(3-methylthiopene) can be platinized by electrochemical reduction of PtC14(2-) at the pair of coated electrodes. The change in conductivity of the poly(3-methylthiophene) with change in redox potential is the basis for amplification of electrical or chemical signals; the conductivity varies by 5 to 6 orders of magnitude upon change in potential from +0.2 (insulating) to +0.7 (conducting) V vs. SCE in aqueous electrolyte. The Pt equilibrates the poly(3-methylthiophene) with the O2/H2O or H2O/H2 redox couples. (Poly(3-methylthiophene)/Pt)-based transistors are shown to be viable room temperature sensors for O2 and H2 in aqueous solution. O2 reproducibly turns on the device. H2 reproducibly turns off the device. A platinized microelectrode of a dimension similar to the microelectrochemical transistor shows only 1.0 nA reduction current upon exposure to 1 atm O2; the current amplification of the transistor is thus a factor greater than 100,000. 收起