Background
Greenhouse gases (GHGs) trap heat and lead to global warming and other severe effects of climate change. Carbon dioxide (CO2) is the main source of GHG, and its capture before entering the atmosphere is an important mitigation approach. Captured CO2 from point-emission sources or via direct air capture (DAC) can be geologically sequestered or converted through biological, electrocatalytic, or photocatalytic technologies into valuable chemical feedstocks or products that can replace fossil-oil or -gas based derivatives. However, many factors hinder photocatalytic CO2 reduction, including light-energy loss, poor conversion efficiency, and low quantum efficiency.
Invention Description
Researchers at Arizona State University and National Tsing Hua University have developed a new dual-fiber photocatalytic reactor for producing formic acid from the valorization of CO2. This reactor design involves coating iron-based metal organic framework, or other nano-scale, photocatalysts onto side-emitting polymeric optical fiber surfaces in conjunction with separate hollow-fiber membranes to deliver bubble-free CO2 into water. This design enables efficient CO2 valorization without the need to separate photocatalysts or recover insoluble CO2. In initial tests, this reactor achieved higher apparent quantum yields and energy efficiency, 94% greater conversion efficiency of CO2, 99% greater product selectivity than traditional photocatalytic reactor designs.
Potential Applications:
- Photocatalytic CO2 reduction
- Formic acid production from CO2 for agriculture, energy, biomedical or other applications
Benefits and Advantages:
- Greater conversion efficiency & product selectivity
- Lower energy consumption
- Sustainable – does not require platinum group or rare earth elements
- Improved quantum efficiency
- High CO2 gas transfer efficiency into water
- High geometric packing density of reactive surfaces within our reactor (m2/m3)
- Decreased material & operating costs