Efficient photocatalytic carbon monoxide production from ammonia and carbon dioxide by the aid of artificial photosynthesis

Zeai Huang; Kentaro Teramura; Hiroyuki Asakura; Saburo Hosokawa; Tsunehiro Tanaka

doi:10.1039/c7sc01851g

Efficient photocatalytic carbon monoxide production from ammonia and carbon dioxide by the aid of artificial photosynthesis

Chem Sci. 2017 Aug 1;8(8):5797-5801. doi: 10.1039/c7sc01851g. Epub 2017 Jun 19.

Authors

Zeai Huang¹, Kentaro Teramura^{1

2}, Hiroyuki Asakura^{1

2}, Saburo Hosokawa^{1

2}, Tsunehiro Tanaka^{1

2}

Affiliations

¹ Department of Molecular Engineering , Graduate School of Engineering , Kyoto University , Kyoto 615-8510 , Japan . Email: teramura@moleng.kyoto-u.ac.jp ; Email: tanakat@moleng.kyoto-u.ac.jp.
² Elements Strategy Initiative for Catalysts and Batteries , Kyoto University , Kyoto 615-8510 , Japan.

Abstract

Ammonium bicarbonate (NH₄HCO₃) was generated by the absorption of carbon dioxide (CO₂) into an aqueous solution of ammonia (NH₃). NH₄HCO₃ was successfully used to achieve highly efficient photocatalytic conversion of CO₂ to carbon monoxide (CO). NH₃ and/or ammonium ions (NH₄⁺) derived from NH₄HCO₃ in aqueous solution were decomposed into nitrogen (N₂) and hydrogen (H₂). Stoichiometric amounts of the N₂ oxidation product and the CO and H₂ reduction products were generated when the photocatalytic reaction was carried out in aqueous NH₄HCO₃ solution. NH₃ and/or NH₄⁺ functioned as electron donors in the photocatalytic conversion of CO₂ to CO. A CO formation rate of 0.5 mmol h^-1 was obtained using 500 mg of catalyst (approximately 7500 ppm) in ambient conditions (303 K, 101.3 kPa). Our results demonstrated that NH₄HCO₃ is a novel inorganic sacrificial reagent, which can be used to increase the efficiency of photocatalytic CO production to achieve one step CO₂ capture, storage and conversion.