Graphene oxide(GO)is regarded as a promising candidate to construct solar absorbers for addressing freshwater crisis,but the easy delamination of GO in water poses a critical challenge for practical solar desalination...Graphene oxide(GO)is regarded as a promising candidate to construct solar absorbers for addressing freshwater crisis,but the easy delamination of GO in water poses a critical challenge for practical solar desalination.Herein,we improve the stability of GO membranes by a self-crosslinking poly(ionic liquid)(PIL)in a mild condition,which crosslinks neighbouring GO nanosheets without blemishing the hydrophilic structure of GO.By further adding carbon nanotubes(CNTs),the sandwiched GO/CNT@PIL(GCP)membrane displays a good stability in pH=1 or 13 solution even for 270 days.The molecular dynamics simulation results indicate that the generation of water nanofluidics in nanochannels of GO nanosheets remarkably reduces the water evaporation enthalpy in GCP membrane,compared to bulk water.Consequently,the GCP membrane exhibits a high evaporation rate(1.87 kg m^(-2)h^(-1))and displays stable evaporation rates for 14 h under 1 kW m^(-2)irradiation.The GCP membrane additionally works very well when using different water sources(e.g.,dye-polluted water)or even strong acidic solution(pH=1)or basic solution(pH=13).More importantly,through bundling pluralities of GCP membrane,an efficient solar desalination device is developed to produce drinkable water from seawater.The average daily drinkable water amount in sunny day is 10.1 kg m^(-2),which meets with the daily drinkable water needs of five adults.The high evaporation rate,long-time durability and good scalability make the GCP membrane an outstanding candidate for practical solar seawater desalination.展开更多
An effective method was used to Ioidal suspensions of highly reduced graphene produce stable and homogeneous coloxide (RGO) in N,N-dimethylformamide (DMF) without the assistance of dispersing agents. According to ...An effective method was used to Ioidal suspensions of highly reduced graphene produce stable and homogeneous coloxide (RGO) in N,N-dimethylformamide (DMF) without the assistance of dispersing agents. According to the results of general characterization, relatively pure graphene sheets with the morphology of single layer or few-layer structure were obtained. Then nanocomposite powders of RGO and poly (vinylidene fluoride) (PVDF) were prepared by vacuum filtration of the mixed dispersions of both components. The nanocomposites exhibit a high-frequency capacitative response with small equivalent series resistance (ESR) at 0.4Q, a nearly rectangular cyclic voltammogram and possess a rapid current response as electrodes for supercapacitor in 5mol/L KOH electrolyte. Furthermore, after 600 galvanostatic charge/ discharge cycles, the supercapacitor still performs a very high stability and efficiency of capacitance.展开更多
基金the financial support of the National Key R&D Program of China(No.2019YFC1806000)the Huazhong University of Science and Technology(No.3004013118)+2 种基金support from the National Natural Science Foundation of China(No.51903099)Huazhong University of Science and Technology(No.3004013134)the 100 Talents Program of the Hubei Provincial Government.Z.D.thanks the Postdoctoral Science Foundation of China(No.0106013063).
文摘Graphene oxide(GO)is regarded as a promising candidate to construct solar absorbers for addressing freshwater crisis,but the easy delamination of GO in water poses a critical challenge for practical solar desalination.Herein,we improve the stability of GO membranes by a self-crosslinking poly(ionic liquid)(PIL)in a mild condition,which crosslinks neighbouring GO nanosheets without blemishing the hydrophilic structure of GO.By further adding carbon nanotubes(CNTs),the sandwiched GO/CNT@PIL(GCP)membrane displays a good stability in pH=1 or 13 solution even for 270 days.The molecular dynamics simulation results indicate that the generation of water nanofluidics in nanochannels of GO nanosheets remarkably reduces the water evaporation enthalpy in GCP membrane,compared to bulk water.Consequently,the GCP membrane exhibits a high evaporation rate(1.87 kg m^(-2)h^(-1))and displays stable evaporation rates for 14 h under 1 kW m^(-2)irradiation.The GCP membrane additionally works very well when using different water sources(e.g.,dye-polluted water)or even strong acidic solution(pH=1)or basic solution(pH=13).More importantly,through bundling pluralities of GCP membrane,an efficient solar desalination device is developed to produce drinkable water from seawater.The average daily drinkable water amount in sunny day is 10.1 kg m^(-2),which meets with the daily drinkable water needs of five adults.The high evaporation rate,long-time durability and good scalability make the GCP membrane an outstanding candidate for practical solar seawater desalination.
文摘An effective method was used to Ioidal suspensions of highly reduced graphene produce stable and homogeneous coloxide (RGO) in N,N-dimethylformamide (DMF) without the assistance of dispersing agents. According to the results of general characterization, relatively pure graphene sheets with the morphology of single layer or few-layer structure were obtained. Then nanocomposite powders of RGO and poly (vinylidene fluoride) (PVDF) were prepared by vacuum filtration of the mixed dispersions of both components. The nanocomposites exhibit a high-frequency capacitative response with small equivalent series resistance (ESR) at 0.4Q, a nearly rectangular cyclic voltammogram and possess a rapid current response as electrodes for supercapacitor in 5mol/L KOH electrolyte. Furthermore, after 600 galvanostatic charge/ discharge cycles, the supercapacitor still performs a very high stability and efficiency of capacitance.