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Abstract Solar steam generation technologies have gained increasing attention due to their great potential for clean water generation with low energy consumption. The rational design of a light absorber that can maximize solar energy utilization is therefore of great importance. Here, the synthesis of Ni@C@SiO2core–shell nanoparticles as promising light absorbers for steam generation by taking advantage of the plasmonic excitation of Ni nanoparticles, the broadband absorption of carbon, and the protective function and hydrophilic property of silica is reported. The nanoparticle‐based evaporator shows an excellent photothermal efficiency of 91.2%, with an evaporation rate of 1.67 kg m−2 h−1. The performance can be further enhanced by incorporating the nanoparticles into a polyvinyl alcohol hydrogel to make a composite film. In addition, utilizing the magnetic property of the core–shell particles allows the creation of surface texture in the film by applying an external magnetic field, which helps increase surface roughness and further boost the evaporation rate to as high as 2.25 kg m−2 h−1.
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Plasma‐catalytic synthesis of acrylonitrile from methane and nitrogen
Abstract In this work, we demonstrate plasma‐catalytic synthesis of hydrogen and acrylonitrile (AN) from CH4and N2. The process involves two steps: (1) plasma synthesis of C2H2and HCN in a nominally 1:1 stoichiometric ratio with high yield up to 90% and (2) downstream thermocatalytic reaction of these intermediates to make AN. The effect of process parameters on product distributions and specific energy requirements are reported. If the catalytic conversion of C2H2and HCN in the downstream thermocatalytic step to AN were perfect, which will require further improvements in the thermocatalytic reactor, then at the maximum output of our 1 kW radiofrequency 13.56 MHz transformer, a specific energy requirement of 73 kWh kgAN−1was determined. The expectation is that scaling up the process to higher throughputs would result in decreases in specific energy requirement into the predicted economically viable range less than 10 kWh kgAN−1.
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- PAR ID:
- 10482018
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- AIChE Journal
- Volume:
- 70
- Issue:
- 1
- ISSN:
- 0001-1541
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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