Tamura Katsunori, Oshima Yuri, Fuse Yuta, Nagaoka Noriyuki, Kunoh Tatsuki, Nakanishi Makoto, Fujii Tatsuo, Nanba Tokuro, Takada Jun
Graduate School of Natural Science and Technology, Okayama University, 700-8530 Okayama, Japan.
Bengala Techno-Lab, 216-0007 Kawasaki-shi, Kanagawa, Japan.
ACS Omega. 2022 Apr 10;7(15):12795-12802. doi: 10.1021/acsomega.1c07390. eCollection 2022 Apr 19.
Inorganic pigments have been widely used due to their low cost of production, strong hiding power, and chemical resistance; nevertheless, they have limited hue width and chromaticity. To eliminate these disadvantages, we herein propose the use of an ingenious biotemplate technique to produce Al-enriched biogenic iron oxide (BIOX) materials. Spectrophotometric color analysis showed that high levels of Al inclusion on heat-treated BIOX samples produced heightened yellowish hues and lightness. The Al-enriched BIOX sheaths exhibited a stable tubular structure and excellent thermal stability of color tones after heating at high temperatures and repetitive heat treatments. Ultrastructural analysis and mechanical destruction experiments revealed that the highly chromatic orange-hue of these pigments are ascribed probably to an ingenious cylindrical nanocomposite architecture composed of putative Fe-included low crystalline Al oxide regions and hematite particles embedded therein. The present work therefore demonstrates that the bioengineered material can serve as an epochal orange-hued inorganic pigment with low toxicity and marked thermostability that should meet large industrial demand.
无机颜料因其生产成本低、遮盖力强和耐化学性而被广泛使用；然而，它们的色调宽度和色度有限。为了消除这些缺点，我们在此提出使用一种巧妙的生物模板技术来制备富铝生物源氧化铁（BIOX）材料。分光光度颜色分析表明，热处理后的BIOX样品中高含量的铝夹杂产生了更高的黄色调及亮度。富铝BIOX鞘呈现出稳定的管状结构，并且在高温加热和重复热处理后具有出色的色调热稳定性。超微结构分析和机械破坏实验表明，这些颜料高度饱和的橙色调可能归因于一种巧妙的圆柱形纳米复合结构，该结构由假定的含铁低结晶氧化铝区域和嵌入其中的赤铁矿颗粒组成。因此，目前的工作表明，这种生物工程材料可以作为一种划时代的橙色无机颜料，具有低毒性和显著的热稳定性，应该能够满足大规模的工业需求。
