Water evaporation, a promising and environmentally friendly technology driven by local hot spots on the water-air interface, is an efficient way to utilize solar energy. Herein, we present a novel laminar solar absorber consisting of graphite powder (GP) and a semipermeable collodion membrane (SCM) as an integrated structural system for highly efficient water evaporation. The GP/SCM composite can efficiently convert the absorbed solar energy to heat energy , e.g., the 8 mg-GP/SCM (i.e., the GP/SCM with 8 mg GP added) enables water evaporation with high efficiency of 56.8% under 1.5 kW/m 2 irradiation and 65.8% under 3 kW/m 2 irradiation, respectively. Cycling tests verify that the GP/SCM could retain stable water evaporation performance over 20 cycles under the same conditions. Contrast experiments show that the other carbon-containing solar-absorbers, such as acetylene black (AB) and graphene nanoplates (GNPs) in SCM, display relatively low evaporation efficiency of 41.4% and 36.7%, respectively, under the simulated solar irradiation with a light density of 1.5 kW/m 2 . The laminar GP/SCM composite obtained in our work is low-cost, easy-to-prepare, recyclable, and highly efficient in its photothermal performance, so that it distinctly contributes to water evaporation.
Baojie Dou,Jianwu Lan,Shiying Lang,Yazhou Wang,Lin Yang,Hongyu Liu,Yafang Wang,Anrong Yao,Shaojian Lin
Development of multifunctional materials for efficient treatment of complex effluents containing water-insoluble oils and water-soluble dyes is highly desired. In this work, a multifunctional Ag/AgCl decorated CO 2 - responsive cotton membrane (Ag/AgCl@PCM) was successfully fabricated for simultaneous or successive removal of oils and dyes (both cationic and anionic dyes). Through achieving protonation and deprotonation in response to the CO 2 , the as-prepared Ag/AgCl@PCM could reversibly switch from superhydrophobic (uncharged) state to superhydrophilic (charged) state. Moreover, the Ag/AgCl endowed the Ag/AgCl@PCM with visible light photocatalytic activity . Based on these ingenious features, the as-prepared Ag/AgCl@PCM could bidirectional separation of various oil/water mixtures with high separation efficiencies (≥97.50%), accompanying with satisfactory fluxes, due to controllable wettability upon CO 2 stimulation. Moreover, the as-prepared Ag/AgCl@PCM exhibited stable oil/water separation property, even under various adverse environmental conditions. Meanwhile, the Ag/AgCl@PCM could eliminate the dyes in wastewater through adsorption for anionic dyes and photocatalysis for cationic dyes. The results presented that MB (anionic dye) could be efficiently removed by the Ag/AgCl@PCM under both static and dynamic states in the presence of CO 2 . The maximum static adsorption capacity of the Ag/AgCl@PCM toward MB reached 2168.47 mg g −1 with a fast adsorption rate (12 min of adsorption equilibrium time). For the removal of cationic dyes, the photo-degradation efficiency of the Ag/AgCl@PCM toward RhB (cationic dye) was up to 94.30% within 6 h. Most importantly, the as-prepared Ag/AgCl@PCM exhibited photo-induced self-cleaning performance due to the existence of Ag/AgCl, which endowed it with excellent recyclability. Additionally, the as-prepared Ag/AgCl@PCM displayed outstanding antibacterial activity . In summary, the Ag/AgCl@PCM could be viewed as a satisfactory material for oil/water separation and dyes removal and exhibits great potential in wastewater remediation.
危险品化学品经营许可证（带存储）