受槐樹啟發！無電鍍制備鎳黑/石墨烯膜，用于太陽能驅動界面蒸發

1成果簡介

太陽能驅動的界面蒸發為高效光熱轉換提供了極具前景的方法。受日本槐樹紋理樹皮高效光捕獲效應的啟發，本文，長春工業大學孫德 教授在《Langmuir》期刊發表名為“Electroless Plating Preparation of Biomimetic Nickel-Black/Graphene Membranes for Solar-Driven Interfacial Evaporation”的論文，研究通過無電鍍工藝成功開發出類樹皮分級鎳黑/石墨烯光熱轉換膜（E-Ni/Gr）。分級結構增強了光捕獲能力，而固有半導體吸收帶隙與碳組分寬帶吸收的協同效應共同提升了光學吸收效率，達到83.21%。在1 kW·m–2輻照下，添加20 mL石墨烯懸浮液的E-Ni/Gr-20膜蒸發速率達1.62 kg·m–2·h–1，光熱轉換效率達91.25%。該膜還展現出卓越的穩定性（經20次循環后仍保持1.3 kg·m–2·h–1蒸發速率）和脫鹽性能（NaCl截留率>99%）。本研究為開發高效穩定的仿生光熱材料提供了重要啟示。

2圖文導讀

圖1.aDesigns of E-Ni/Gr membrane;bThe process diagram of preparing a nickel black-graphene photothermal conversion membrane by the electroless plating method;cThe dual-action mechanism, light trapping effect, and hydrophobicity of the E-Ni/Gr membrane.

圖2. Microscopic morphology and element distribution of the E-Ni/Gr membrane:aEffects of the amounts of graphene on the nickel black-graphene photothermal conversion membrane;bSEM image of the nickel black-graphene photothermal conversion membrane prepared by electroless plating: (b1) ×1000; (b2) ×5000;cSophora japonica tree;dThe EDS of C, Ni, and S on the E-Ni/Gr membrane surface.

圖3.aXPS spectrum of the nickel black-graphene photothermal conversion membrane;bXRD pattern of the nickel black-graphene photothermal conversion membrane;cRaman spectra of the nickel black-graphene photothermal conversion membrane;dWater contact angles of the E-Ni/Gr membrane.

圖4. Photothermal properties of the nickel black-graphene photothermal conversion membrane (light intensity: 1 sun):aThe working principle of the membrane under light conditions;bThe absorption rate of E-Ni/Gr;cThe reflectivity of E-Ni/Gr;dThe average absorptivity of E-Ni/Gr;eInfrared thermal image of membrane: (e1) wet membrane; (e2) dry membrane;fWet membrane surface average temperature;gAverage surface temperature of the dry membrane.

圖5. Interface evaporation performance of the nickel black-graphene photothermal conversion membrane:aThe weight loss curve of the solar interface evaporator with the nickel black-graphene photothermal conversion membrane (illuminate under 1 sun);bEvaporation rate of the nickel black-graphene photothermal conversion membrane (illuminate under 1 sun);cSolar-vapor conversion efficiency of the nickel black-graphene photothermal conversion membrane (illuminate under 1 sun);dEffect of irradiation intensity on the E-Ni/Gr-20 evaporation rate;eEffect of NaCl concentration on the evaporation rate of E-Ni/Gr-20;fDesalination performance of E-Ni/Gr-20;(g, h)The abrading experiment of the E-Ni/Gr-20 membrane;iEvaporation rate and rejection rate of the membrane after abrasion;jSEM image of the membrane after abrading;kChange of irradiation intensity of sunlight and environmental temperature during the outdoor test;lMass changes of E-Ni/Gr-20 during the day.

3小結

受槐樹粗糙表面卓越的光熱效應啟發，本研究成功開發出用于光熱轉換的石墨烯修飾鎳黑膜（E-Ni/Gr）。該仿生膜在自驅動光熱轉換（SDIE）領域展現出優異性能。通過無電鍍法在鎳泡沫基底上構建出具有仿生疏松多孔結構的鎳黑/石墨烯復合層。E-Ni/Gr-20樣品實現91.25%的光熱轉換效率與1.62 kg·m?2·h?1的蒸發速率，平均光吸收率達83.21%。該成果揭示了仿生分級結構、碳材料寬譜吸收特性與半導體材料固有吸收帶隙的協同效應機制。通過精確調控石墨烯含量，實現96.2°的水接觸角。優化多孔結構設計使膜在20次循環測試中保持穩定蒸發性能（1.3 kg·m?2·h?1，保留率>99%）。這種兼具高效光熱轉換、長期防污性能與經濟可行性的復合膜設計，為新一代太陽能海水淡化技術發展奠定了重要材料基礎，在應對全球淡水危機方面具有重大應用價值。

來源：材料分析與應用