Abstract Many semiconductors with broad solar spectrum absorption have always been pursuing for the effective photothermal conversion process. However, it is still a challenge to modulate the structural and bandgap of semiconductors to enhance the photothermal activity synergistically. In this work, facile prepared mesoporous CuO displays a narrower bandgap than non-porous CuO, leading to highly efficient solar-thermal conversion. Mesoporous CuO shows obvious broad and strong optical absorption, especially in the visible light region. It is noteworthy that the mesoporous CuO nanofluids exhibit good dispersibility in water. Different concentrations of mesoporous CuO nanofluids have higher temperature rise than non-porous CuO nanofluids. The photothermal conversion efficiency of 50 ppm mesoporous CuO/water nanofluid is 83.66%, compared with 58.86% for 50 ppm CuO/water nanofluid. Mesoporous CuO will bring a new paradigm for mesoporous metal oxide nanofluids as working fluids in direct absorption solar collectors.

中文翻译：

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具有全光谱吸收的介孔 CuO 用于直接吸收太阳能集热器中的光热转换

摘要 许多具有广泛太阳光谱吸收能力的半导体一直在追求有效的光热转换过程。然而，调节半导体的结构和带隙以协同增强光热活性仍然是一个挑战。在这项工作中，简单制备的介孔 CuO 显示出比无孔 CuO 更窄的带隙，从而实现高效的太阳能热转换。介孔CuO表现出明显的广泛而强烈的光吸收，尤其是在可见光区。值得注意的是，介孔CuO纳米流体在水中表现出良好的分散性。不同浓度的介孔CuO纳米流体比无孔CuO纳米流体具有更高的温升。50 ppm介孔CuO/水纳米流体的光热转换效率为83.66%，而58%。86% 对于 50 ppm CuO/水纳米流体。介孔 CuO 将为介孔金属氧化物纳米流体作为直接吸收太阳能集热器中的工作流体带来新的范例。