Rapid and safe implementation of viscous crude oil cleanup is still a daunting challenge. Superhydrophobic materials are outstanding candidates for handling solvent spills, but are limited to recovering low viscosity oil and organic solvents. Hence, a polyurethane foam (PMRP-PU) integrating superelasticity, dual solar-responsive and fire resistance was fabricated by blending MXene and reduced graphene oxide (RGO) via self-foaming method. The surface temperature of the PMRP-PU reached 105 °C after simulated sunlight irradiation for 600 s. PMRP-PU had outstanding adsorption performance for low-viscosity oil and organic solvent (∼70.1 g/g) at room temperature, and the adsorption capacity of high-viscosity oil was also increased by 202.1 % compared with pure PU. Additionally, the adsorption capacity of PMRP-PU-3 remained at 92.7 % of the original level after 20 cycles of experiments. Excellent acid and alkali resistance and high temperature stability also greatly improved the environmental adaptability of the foam. Contrary to the flammability of pure PU, the peak heat release rate and total heat release of PMRP-PU-3 were decreased by 22.6 % and 25.2 %, respectively, and the melt dripping phenomenon disappeared during burning, exhibiting excellent fire safety. Briefly, this polyurethane foam can be repeatedly used for oil spill cleaning, and has a broad development prospect in the field of oil-water separation.
To alleviate resource shortage and environmental pollution, solar energy can be converted into thermal energy stored in phase change materials and in turn generate electrical energy. To enhance the solar energy utilization efficiency of solar-thermal-electrical conversion devices and prevent the heat loss to the environment at night, an intelligent solar-responsive phase-change system is innovatively designed consisting of a graphene aerogel film/paraffin wax stamen with an ultra-high thermal conductivity of 46.7 W m −1 K −1 , and thermally preserving aerogel film/liquid crystal elastomer bilayer petals that can bend solar-responsively by the synergistic effect of solar-thermal energy conversion and heat-induced contraction. The solar-responsive phase-change system achieves daytime blooming for solar-thermal conversion with simultaneous energy storage and nighttime closing for minimizing heat loss to the environment, exhibiting a high solar-thermal conversion and energy storage efficiency of 89.4% and delaying its temperature drop by the thermal preservation effect of the petals. The assembled solar-responsive solar-thermal-electric generator can reach an output voltage of 1033.8 mV at a light intensity of 500 mW cm −2 and continue to generate electrical energy during nighttime, holding tremendous promise in efficient solar energy conversion, storage, and utilization.
Lin Li,Shao Xue,Rong Chen,Qiang Liao,Xun Zhu,Zhibin Wang,Xuefeng He,Hao Feng,Xiao Cheng
In this work, a membraneless photocatalytic fuel cell (PFC) with a solar responsive photoanode and an air-breathing cathode was developed to simultaneously degrade the wastewater and generate electricity. The performance characteristics of the developed PFC was examined for the real application purpose. Particular attention was paid to investigate the effect of the fuel and electrolyte types on the cell performance. Experimental results showed that the alkaline electrolyte yielded the maximum power density of 4.1 mW cm −2 , which was much better than the neutral electrolyte with the maximum power density of 0.5 mW cm −2 . Long-term performance measurements also showed that the cell performance was rather stable under the alkaline electrolyte but dramatically reduced under the neutral electrolyte in the 3-hour constant current density operation. Regarding the fuel types, the PFC exhibited appreciable performance for both alcohols and saccharides . Methanol and glycerol produced the maximum power densities of 4.08 and 2.58 mW cm −2 , while D-glucose and D-xylose generated the maximum power densities of 3.92 and 3.67 mW cm −2 , respectively. The difference in the cell performance can be attributed to the difference in the molecular structure, i.e., the fuel with a simpler molecular structure and a shorter carbon chain could yield better performance. Besides, the PFCs also showed favorable performances in some complex wastes, such as artificial sewage, Coca Cola and urine. For the air-breathing cathode design, the oxygen concentration effect on the PFC performance was also studied. It was found that increasing the oxygen concentration from 5% to pure oxygen led to the improvement of the maximum power density from 3.5 to 5.2 mW cm −2 .
危险品化学品经营许可证（带存储）