| Light-distillation,which is of great help in alleviating energy shortages and freshwater resources,is a technology that uses solar energy to produce clean water.However,the traditional light-distillation has a low effective utilization rate of solar.In order to solve this problem,researchers had proposed a solar-driven interface steam generation system(SISGS),the evaporation of water occurs at the liquid-gas interface,which can be green,environmentally friendly and efficient use of solar energy to produce clean water.Solar absorber is a the key of the SISGS,the solar absorber that can efficiently use solar energy should meet the following conditions,floating on the water surface,effectively absorbing sunlight and converting it into heat energy,has a hydrophilic structure and transporting water to the interface.In recent years,solar absorbers had prepared and have good rate of absorption and conversion rates for solar steam generation by using metal nanoparticles and graphene oxide,but raw materials is expensive in life,they are difficult to realize large-scale applications.In this paper,the cheap and efficient solar absorbers were prepared for SISGS by using attapulgite(ATP),halloysite(HNTs)and yam,and solar steam efficiency of the absorbers was studied in simulated SISGS.This paper is divided into three parts.The first part,the attapulgite-based solar absorber(APAC)was prepared by aqueous solution polymerization using acrylamide(AM),N,N-methylenebisacrylamide(MBA)and ATP as raw materials,and then,the surface was carbonized to obtain double-layer attapulgite-based solar absorber(BAPAC).The morphology of APAC and BAPAC was analyzed by SEM.It was found that APAC and BAPAC have lamellar structures.The pore properties of APAC were characterized by BET.It was found that APAC has both microporous and mesoporous structures.The hydrophilicity of the two samples was characterized by contact angle test,and it was found that APAC is super-hydrophilic,while the carbon layer of BAPAC(F-APAC)is hydrophobic.The light absorption of BAPAC was tested by near-ultraviolet-visible-near-infrared absor-ption and found it has a light absorption rate close to 99%.The solar steam efficiency of the absorber was tested by a solar water vapor experiment,and it was found that solar steam efficiency of the APAC is about 40% in one sun and solar steam efficiency of the BAPAC is about 80%.The second part,the halloysite-based solar absorber(HNTsA)was prepared by aqueous solution polymerization using AM,MBA and HNTs as raw materials,and then,the surface was carbonized to obtain a double-layered halloysite-based solar absorber(F-HNTsA).At the same time,a mixed clay-based solar absorber(ATP-HNTsA)was prepared by aqueous solution polymerization using AM,MBA,ATP and HNTs as raw materials,and the surface was carboniz ed to obtain a double-layer mixed clay-based solar absorber(F-ATP-HNTsA).The morphology of the sample was characterized by SEM,it was found that the sample have a lamellar structure.The pore properties of HNTsA and ATP-HNTsA were characterized by BET,it was found that the the solar absorbers have both microporous structure.The hydrophilicity of HNTsA and ATP-HNTsA was characterized by water contact angle test,it was found that HNTsA is hydrophobic and ATP-HNTsA is super-hydrophilic.The light absorption of F-HNTsA and F-ATP-HNTsA was tested by near-ultraviolet-visible-near-infrared absorption and was found F-HNTsA and F-ATP-HNTsA have light absorption rate close to 80% in near-ultraviolet-visible region.The solar steam efficiency of the absorber was tested by a solar water vapor experiment,and it was found that solar steam efficiency of the F-HNTsA is about 57% in one sun and solar steam efficiency of the F-ATP-HNTsA is about 84%.The third part,the solar absorber of the yam was prepared by freeze-dried using yam as raw material,and the above samples are processed at different temperatures to obtain more optimized performance.The morphology of the sample was characterized by SEM.It was found that the morphology of yam solar absorber are orderly,the skeleton structure of the solar absorber of treating was damaged increase by temperature.The pore properties of the yam solar absorber were characterized by BET,it was found that all the light absorbers have both a microporous structure and a mesoporous structure.The hydrophilicity of the solar absorber was characterized by a water contact angle test,and it was found that the light absorbers are all super hydrophilic.The light absorption of the yam solar absorber was tested by near-ultraviolet-visible-near-infrared absorption and found the treated yam have light absorption rate close to 90% in near-ultraviolet-visible region.The solar steam efficiency of the absorber was tested by a solar water vapor experiment,and it was found that the yam treated at 200 ? in 1 sun has the best performance,and its solar steam efficiency is about 90%. |
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