تهيه و بررسي خواص هيدروژل پلي وينيل الكل/پلي وينيل پيروليدون به عنوان خنك كننده صفحات خورشيدي

Preparation an‎d investigation of polyvinyl alcohol / Polyvinyl pyrrolidone hydrogel properties as solar panel cooling

شيمي پليمر

Solar panels play a significant role in producing clean energy due to their high efficiency, lack of pollutant emissions, an‎d lower maintenance costs compared to other renewable sources. However, the increase in temperature gradually causes a decrease in the power output an‎d lifespan of the panels. In this study, to cool solar panels through the water evaporation process, a polyvinyl alcohol-polyvinyl pyrrolidone hydrogel containing calcium chloride dihydrate salt was prepared using potassium persulfate as an initiator in different ratios. The optimal ratio of 40/60 polyvinyl pyrrolidone to polyvinyl alcohol, with a swelling percentage close to 500%, was selec‎ted based on water absorption an‎d evaporation data an‎d used as the cooling agent for the solar panel. The successful formation of the hydrogel network structure was confirmed using the FTIR test. The surface morphology was also examined using SEM an‎d BET tests, an‎d the results indicate a relatively uniform distribution of the hydrated salt an‎d confirm the porous structure of the hydrogel with an average pore size of 33 nm. The graphs obtained from the TGA test also indicate a 90 percent water content in the hydrogel structure. Additionally, the results of the tensile mechanical test showed a Youngʹs modulus of 0.12 an‎d a 51.24% elongation for the 40/60 polyvinylpyrrolidone-polyvinyl alcohol hydrogel, which, compared to other hydrogels, underwent deformation under lower stress an‎d exhibited lower mechanical resistance. The solar panel temperature data over the test period indicated effective cooling up to 4 degrees Celsius under 20% humidity compared to 1 degree Celsius under 10% humidity. Additionally, with an increase in the number of times the hydrogel was used, the cooling capacity of the hydrogel gradually decreased from 4 degrees Celsius to 1 degree Celsius. Gradually, the cooling capacity of the hydrogel decreased from 4 to 1 degree Celsius.

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