Realizing efficient natural sunlight-driven photothermal selective catalytic reduction of nitrogen oxides by AlNx assisted W doped Fe2O3 nanosheets

• Published in: Solar energy materials and solar cells 2020-05, Vol.208, p.110395, Article 110395
• Main Authors: Bai, Xianhua, Yuan, Dachao, Xu, Yingqi, Li, Yaguang, Lu, Wen, Wang, Shufang, Fu, Guangsheng, Hu, Yong
• Format: Article
• Language: English
• Subjects: AlNx; Catalysts; Chemical reduction; Fe2O3; Ferric oxide; Graphene; Irradiation; Low temperature; Nanosheets; Nitrogen oxides; NOx SCR; Photocatalysis; Photochemicals; Photothermal; Photothermal conversion; Polyvinyl alcohol; Radiation; Selective catalytic reduction; Selectivity; Sulfur dioxide; Sunlight
• ISSN: 0927-0248; 1879-3398
• DOI: 10.1016/j.solmat.2020.110395

Photocatalytic selective catalytic reduction of nitrogen oxides (NOx SCR) is a green and effective method to eliminate NOx. But the natural sunlight-driven NOx SCR is not realized due to the low temperature under sparse sunlight irradiation and the lack of highly active catalysts. To solve those problems, we selected a commercial AlNx film which can heat the catalysts to 270 °C just under one standard solar irradiation because of its full sunlight absorption and low radiation characteristics, enabling to onset NOx SCR. Further, a polyvinyl alcohol assisted graphene oxides templated method was developed to synthesize the W doped Fe2O3 nanosheets on a large scale, which can be used as efficient NOx SCR catalysts with high N2 selectivity, excellent SO2 and H2O resistances. As a result, the AlNx assisted W doped Fe2O3 nanosheets showed 92% and 90% NO conversion rate under one solar irradiation and outdoor sunlight irradiation respectively without second energy input, first time of realizing natural sunlight-driven photothermal NOx SCR. This strategy demonstrates a great potential on second energy free industrialized NOx SCR. We found that a commercial AlNx film can convert 1 kW m−2 of sunlight as more than 270 °C high temprature due to its full sunlight absorption and low heat emission. As a result, the AlNx assisted W doped Fe2O3 nanosheets showed 92% NOx SCR efficiency under 1 kW m−2 of sunlight irradiation without second energy input. [Display omitted] •AlNx film can convert 1 kW m−2 of sunlight as more than 270 °C high temperature.•W doped Fe2O3 nanosheets with high surface area of 310 m2 g−1 is synthesized at gram scale.•The NOx SCR efficiency of W doped Fe2O3 nanosheets is 28.3 times higher than that of normal W doped Fe2O3 structures.•One solar-driven photothermal AlNx assisted W doped Fe2O3 nanosheets shows 92% NOx SCR efficiency.•Natural sunlight-driven photothermal NOx SCR is realized by AlNx assisted W doped Fe2O3 nanosheets.