| 摘 要： | A new hybrid cycle to produce hydrogen from water, which consists of a thermochemical reaction (3) and an electrochemical reaction (4), has been devised.2KNO_3+I_2→2KI+2NO+2O_2, (3)2NO+3/2 O_2+2KI+H_2O→2KNO_3+I_2+H_2. (4)The change in free energy of the reaction (3) decreases as temperature rises. and the temperature, at which the △G° is zero, is about 950 K. The electrochemical reaction (4) could be divided intoanode 2I~-→I_2+2e~- (7)andcathode 2H~++2e~-→H_2 (8)in electrolysis cell with an ion-exchange resin. So, the standard equilibrium decomposition voltage of the reaction (4) is 0.54 V.The preliminary experimental investigations were carried out. The yields of the reaction (3) increase as the temperature rises, and KNO_3 is converted into KI casily and rapidly, when reacting with gaseous iodine above 1000 K. The polarizations of the electrolysis reaction were small. The sum of the equilibrium decomposition voltages and overvoltages—0.56, 0.65 and 0.78 V at 100, 500 and 1000 mA·cm~(-2), respe
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