近年來，基於觸媒材料成本高昂和熱催化須額外耗能以及光催化的光頻譜利用效率低等缺點，許多研究致力於尋找替代更符合經濟效益且能更實際應用的催化方法，如能充分利用太陽能可再生能源進行光熱催化，而不是單靠施加熱能來克服催化氧化過程中的活化能，達到將汙染物降解以免於二次污染。所以我們將催化反應與光熱材料結合，提供了一種利用太陽能改善熱催化與光催化的研究。首先使用毒性較低的溶劑以綠色合成得到Mn-MIL-100接著在氮氣氣氛下通過高溫碳化得到MnO@C-800，並通過水熱法進一步改質碳化後樣品，通過吸附與光熱催化移除室內有毒氣體甲醛。 結果表明，錳氧化物奈米碳材料在太陽模擬器的照射下會自然升溫到~60oC，並能在30分鐘內降解~100%(4ppm)的甲醛。我們所合成的錳氧化物奈米碳材料表現優異的甲醛移除活性，可歸因於MnO2與奈米石墨碳之間的協同光熱效應，增強了全太陽光光譜的利用效率，尤其是在近紅外區域有優異的吸收響應。另外在太陽光模擬器的照射下錳氧化物奈米碳材料能夠生成超氧自由基且有效的貢獻在甲醛的催化反應，並且我們透過單純熱催化與光加熱催化的實驗去進行光熱催化模式與機制探討。該結果展示了一種有效利用取之不盡的太陽能而非外加熱能來驅動催化反應的理想方法，是能降低實際應用上的成本需求並同時提高傳統光催化劑催化效率的有前景之策略。

Recently, the pollutant removal reaction was known for the high cost of catalyst materials, extra energy consumption for thermal catalysis, and low efficiency of light absorption for photocatalysis. We need to find a solution to achieve full utilization of solar renewable energy by thermal energy to overcome the activation energy in the catalytic oxidation process and avoid secondary pollution. In this study, we combined catalytic reactions with photothermal materials to improve thermal catalysis and photocatalysis by solar energy. In this current study, Mn-MIL-100 derived Mn-based carbon materials were found to be an effective material for the removal of gaseous formaldehyde (HCHO). The results show that the Mn-based carbon materials reached ~60oC under the irradiation of a solar simulator and removed ~100% (4ppm) formaldehyde within 30 minutes. The as-synthesized sample exhibits excellent formaldehyde removal efficiency, which can be attributed to the synergistic photothermal effect between MnO2 and graphitic carbon and enhanced the utilization of sunlight, especially in the near-infrared region. In addition, Mn-based carbon materials can generate superoxide radicals and effectively enhance formaldehyde removal efficiency under the irradiation of a solar simulator. We also conducted experiments to prove the mechanism of photothermal reaction mode. This result provides a facile, simple, and fast approach to efficiently utilize the inexhaustible solar energy rather than extra heating energy to drive catalytic reactions. Thus, this study shows a way to reduce the cost requirements for practical applications as well as improve the catalytic efficiency of traditional thermal catalysts. So, it’s a promising strategy to be eco-friendly and economical for indoor HCHO removal.

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