Highly porous light absorbers are fabricated based on polypyrrole (PPy)-coated carbon nanotube (CNT). Carbon nanotube sponge (CNTS) or carbon nanotube array (CNTA) with three-dimensional (3D) network structure is the framework of porous light absorbers. Both PPy@CNTS and PPy@CNTA composites exhibit excellent light absorption of the full solar spectrum. The CNTS and CNTA with porous structures have extremely large effective surface area for light absorption and for water evaporation that has great practical benefit to the solar-driven vapor generation. The PPy layer on CNT sidewalls significantly improves the hydrophilicity of porous CNTS and CNTA. The good wettability of water on CNT sidewalls makes water transport in porous CNT materials highly efficient. The PPy@CNTS and PPy@CNTA light absorbers achieve high water evaporation rates of 3.35 and 3.41 kg m⁻² h⁻¹, respectively, under 1-sun radiation. The orientation of nano channels in CNTA-based light absorbers also plays an important role in the solar-driven vapor generation. The water transport and vapor escape are more efficient in CNTA-based light absorbers as compared to the CNTS-based light absorbers due to the relatively short path for the water transport and the vapor escape in CNTA-based light absorbers.

中文翻译：

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基于聚吡咯涂层 3D 碳纳米管材料的太阳能蒸发器，用于高效太阳能驱动蒸汽产生

高多孔光吸收器是基于聚吡咯（PPy）涂覆的碳纳米管（CNT）制成的。具有三维（3D）网络结构的碳纳米管海绵（CNTS）或碳纳米管阵列（CNTA）是多孔光吸收器的框架。PPy@CNTS 和 PPy@CNTA 复合材料均表现出对全太阳光谱的出色光吸收。具有多孔结构的CNTS和CNTA具有极大的光吸收和水蒸发的有效表面积，这对太阳能驱动的蒸汽产生具有很大的实际好处。CNT侧壁上的PPy层显着提高了多孔CNTS和CNTA的亲水性。水在碳纳米管侧壁上良好的润湿性使得多孔碳纳米管材料中的水传输非常高效。PPy@CNTS和PPy@CNTA光吸收剂在1太阳辐射下分别实现了3.35和3.41 kg m ^-2 h ^{-1的高水蒸发率。}基于 CNTA 的光吸收器中纳米通道的方向在太阳能驱动的蒸汽产生中也发挥着重要作用。与基于CNTS的光吸收剂相比，基于CNTA的光吸收剂的水传输和蒸汽逸出更有效，因为基于CNTA的光吸收剂中水传输和蒸汽逸出的路径相对较短。