Study On Sunlight Enhanced Adsorbent For Uranium Extration From Seawater

Nuclear power has been widely developed because of its high energy density and low greenhouse gas emissions.Uranium is a key nuclear fuel,so the rapid development of nuclear energy will inevitably lead to an increase in the demand for uranium.According to the report,the confirmed uranium reserves on land are only 7.6million tons,which can only be used by human beings for about 100 years.Therefore,there is an urgent need to find a new source of continuous supply of uranium.It is estimated that the total amount of uranium that can be exploited in the ocean is about4.5 billion tons.However,due to the high salinity and complex composition of seawater,there are many difficulties in the practical application of extracting uranium from seawater.The South China Sea is located in the southernmost part of China,which is rich in light resources.Rational design of adsorbent that targets the marine factors is highly possible to enhance the efficiency for uranium extraction from natural seawater.Herein,based on the photoinduced photothermal,photoelectric,and photocatalytic effects of black phosphorus（BP）nanosheets,a BP-PAO fiber with enhanced uranium extraction capacity and high antibiofouling activity is fabricated by compositing BP nanosheets into polyacrylamidoxime（PAO）.The photothermal effect increases the coordination interaction between UO₂²⁺and the functional amidoxime group,and the photoelectric effect produces the surface positive electric field that exhibits electrostatic attraction to the negative[UO₂（CO₃）₃]^4-,which all increase the capacity for uranium adsorption.The photocatalytic effect endows the adsorbent with high antibiofouling activity by producing biotoxic reactive oxygen species.Due to these three photoinduced effects,the photoinduced BP-PAO fiber shows a high uranium adsorption capacity of 11.76 mg g^-1,which is 1.50 times of the PAO fiber,in bacterial contained natural seawater.The results show that BP-PAO,as an efficient adsorbent for extracting uranium from seawater,can effectively improve the performance of extracting uranium from seawater by utilizing the abundant light resources in the ocean.This study is of great significance to broaden the new ideas of uranium extraction from seawater.