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Abstract Converting CO2to value‐added chemicals,e. g., CH3OH, is highly desirable in terms of the carbon cycling while reducing CO2emission from fossil fuel combustion. Cu‐based nanocatalysts are among the most efficient for selective CO2‐to‐CH3OH transformation; this conversion, however, suffers from low reactivity especially in the thermodynamically favored low temperature range. We herein report ultrasmall copper (Cu) nanocatalysts supported on crystalline, mesoporous zinc oxide nanoplate (Cu@mZnO) with notable activity and selectivity of CO2‐to‐CH3OH in the low temperature range of 200–250 °C. Cu@mZnO nanoplates are prepared based on the crystal‐crystal transition of mixed Cu and Zn basic carbonates to mesoporous metal oxides and subsequent hydrogen reduction. Under the nanoconfinement of mesopores in crystalline ZnO frameworks, ultrasmall Cu nanoparticles with an average diameter of 2.5 nm are produced. Cu@mZnO catalysts have a peak CH3OH formation rate of 1.13 mol h−1per 1 kg under ambient pressure at 246 °C, about 25 °C lower as compared to that of the benchmark catalyst of Cu−Zn−Al oxides. Our new synthetic strategy sheds some valuable insights into the design of porous catalysts for the important conversion of CO2‐to‐CH3OH.
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Reversible and Ultrasensitive Detection of Nitric Oxide Using a Conductive Two‐Dimensional Metal–Organic Framework
Abstract This paper describes the use of a highly crystalline conductive 2D copper3(hexaiminobenzene)2(Cu3(HIB)2) as an ultrasensitive (limit of detection of 1.8 part‐per‐billion), highly selective, reversible, and low power chemiresistive sensor for nitric oxide (NO) at room temperature. The Cu3(HIB)2‐based sensors retain their sensing performance in the presence of humidity, and exhibit strong signal enhancement towards NO over other highly toxic reactive gases, such as NO2, H2S, SO2, NH3, CO, as well as CO2. Mechanistic investigations of the Cu3(HIB)2‐NO interaction through spectroscopic analyses and density functional theory revealed that the Cu‐bis(iminobenzosemiquinoid) moieties serve as the binding sites for NO sensing, while the Ni‐bis(iminobenzosemiquinoid) MOF analog shows no noticeable response to NO. Overall, these findings provide a significant advance in the development of crystalline metal‐bis(iminobenzosemiquinoid)‐based conductive 2D MOFs as highly sensitive, selective, and reversible sensing materials for the low‐power detection of toxic gases.
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- PAR ID:
- 10571399
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 64
- Issue:
- 7
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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