Preparation And Performance Of MoS₂-bamboo Based Photothermal Conversion Devices

In order to alleviate the current shortage of fresh water resources and the need for high-value utilization of bamboo,in this study,MoS₂/bamboo photothermal conversion devices with three different shapes were prepared by using MoS₂ as the substrate and surface self-assembly technology.Through seawater desalination test,the main research results and conclusions are as follows:（1）The natural bamboo was cut into bamboo blocks along the vertical growth direction after removing the green bamboo yellow.The MoS₂ nanoparticles were loaded on the cross section of bamboo by hydrothermal synthesis method to prepare 2D MoS₂/bamboo photothermal converter.The maximum light absorption of 2D MoS₂/bamboo in the wavelength range of 250 nm-2500 nm is more than 80%.Under one sunlight intensity,the evaporation rate of 2D MoS₂/bamboo is 1.095 g·m^-2·h^-1;The light heat conversion efficiency is 78.20%;After continuous testing for 8 hours,the photothermal conversion efficiency was 82.50%;After 10 cycles,the average water evaporation is 1.083 kg·m^-2;The concentrations of Na⁺,Mg²⁺,K⁺and Ca²⁺in the evaporated fresh water decreased to 13.08 mg/L,0.94 mg/L,3.00 mg/L and 1.24 mg/L respectively.（2）The natural bamboo was sawn into arch shape along the longitudinal section after removing bamboo green and bamboo yellow,and the MoS₂ nanoparticles were loaded on the longitudinal section of bamboo by hydrothermal synthesis method to prepare 3D Arched MoS₂/bamboo photothermal converter.The maximum light absorption of 3D Arched MoS₂/bamboo in the wavelength range of 250 nm-2500 nm is greater than 80%.Under one sunlight intensity,the evaporation rate of 3D Arched MoS₂/bamboo is 1.277 g·m^-2·h^-1;The light heat conversion efficiency is 91.20%;After continuous testing for 8 hours,the photothermal conversion efficiency was 93.83%;After 10 cycles,the average water evaporation is 1.255 kg·m^-2;The concentrations of Na⁺,Mg²⁺,K⁺and Ca²⁺in the evaporated fresh water decreased to 2.77 mg/L,0.12 mg/L,0.39 mg/L and 0.73 mg/L respectively.（3）A 3D sunflower shaped MoS₂/bamboo photothermal converter was prepared by cutting natural bamboo into short and uniform bamboo sticks,fixing them into sunflower shape with polyethylene foam,and loading MoS₂ nanoparticles on the cross section of bamboo by hydrothermal synthesis.The maximum light absorption of 3D Sunflower shaped MoS₂/bamboo in the wavelength range of 250 nm-2500 nm is more than 80%.Under one sunlight intensity,the evaporation rate of 3D Sunflower shaped MoS₂/bamboo is 1.236 g·m^-2·h^-1;The light heat conversion efficiency is 88.32%;After continuous testing for 8 hours,the photothermal conversion efficiency was 90.58%;After 10cycles,the average water evaporation is 1.219 kg·m^-2;The concentrations of Na⁺,Mg²⁺,K⁺and Ca²⁺in the evaporated fresh water decreased to 13.20 mg/L,1.30 mg/L,1.57 mg/L and 4.64 mg/L respectively.The experimental results show that the three different shapes of MoS₂/bamboo photothermal converters have good seawater evaporation effect and excellent stability,which can effectively alleviate the shortage of fresh water resources.