Preparation And Solar Watre Evaporation/power Generation Performance Of Cellulose-based Solar Thermal Materials

The world is facing challenges of fossil energy crisis,lack of fresh water resources,and increasing water pollution.The utilization of solar energy in seawater desalination,sewage treatment and water evaporation power generation has very good application prospects.Main factors that affect solar water evaporation include the composition and structure of the light-absorbing material,water transport,heat transfer,and so on.In this thesis,CNTs/ATO/ carboxymethyl cellulose gel,Ag/graphene/filter paper and carbonized-oxidized carboxymethyl cellulose were prepared as solar thermal conversion materials with CNTs,ATO,graphene and Ag nanoparticles as solar thermal conversion materials.The structures,composition,optical absorption/photothermal conversion,and hydrophilic properties of the materials were characterized by SEM,XRD,UV-Vis-IR,and contact angle testing.The performance of interfacial solar water evaporation and power generation was investigated.?1?CNTs/ATO/cellulose gel with porous structure was prepared by freeze-drying and cross-linking with CNTs ATO nanoparticles and carboxymethyl cellulose as raw material.Then the performance of solar water evaporation and power generation was investigated.The gel has significant solar absorption/photothermal conversion and hydrophilic properties.The water evaporation rate can reach 1.325 kg·m^-2·h^-1 under one sun illumination and the water evaporation efficiency is 83.2%.The gel is effective in seawater desalination and organic dye treatment.A voltage of 100 m V can be generated during solar evaporation of sea water.?2?Ag/graphene/cellulose paper solar evaporation system was established by loading Ag nanoparticles on filter paper.The system delivers an evaporation rate of 1.36kg·m^-2·h^-1 under one sun illumination and the corresponding water evaporation efficiency is about 86%.The system shows significant performance in seawater desalination and organic dye treatment.The system can generate a voltage of 120 m V while evaporating sea water.?3?Amorphous carbon materials with porous structure were prepared by freeze-drying and carbonization with carboxymethyl cellulose as raw materials.The materials have significant solar absorption/photothermal conversion and hydrophilic properties.The water evaporation rate is 1.09 kg·m^-2·h^-1 under one sun illumination and the evaporation efficiency is 68.4%.The materials can generate power by producing streaming potentials during the evaporating of seawater.A streaming potential as high as350 m V can be generated in 0.7 mol·L^-1 Na Cl solution.