Проблеми застосування поруватого кремнiю для хiмiчного та фотокаталiтичного виробництва водню

• Main Author: Manilov, A. I.
• Format: Article
• Language: English; Ukrainian
• Published: Publishing house "Academperiodika" 2019
• Subjects: поруватий кремнiй; дисоцiацiя води; водень; porous silicon; water dissociation; hydrogen; -
• Online Access: https://ujp.bitp.kiev.ua/index.php/ujp/article/view/2019104

Advantages of the use of silicon and porous silicon (PS) for the chemical production of hydrogen have been analyzed and compared with other fuels. An analytic expression is derived for the dependence of the volume of hydrogen produced at the PS interaction with water on the material porosity, as well as for the corresponding energy yield, when the produced gas is used in the power sources of electronic systems. It is found that the silicon porosity growth results in a reduction of the total volume of hydrogen released in the reaction with water, as compared with the amount of H2 obtained from the initial quantity of raw silicon. This effect is explained by significant losses of a material at PS formation. The ratio between the accumulation of hydrogen in the PS material and silicon losses in the etchant is determined to be optimal for the silicon porosity in the interval of 60–70%. When applying the produced hydrogen in fuel cells, the etching of silicon provides a growth of the output power, but reduces the total amount of the produced energy. Those mechanisms are analyzed to demonstrate the inexpediency of using the composites on the basis of pure nano-PS for the photocatalytic water dissociation.