Innovative nanofiber technology to improve carbon dioxide biofixation in microalgae cultivation

•NPsFe2O3 increased the specific surface areas of the nanofibers.•The nanofibers containing NPsFe2O3 had high CO2 adsorption capacities.•Addition of nanofibers to the cultivation limited the losses of the injected gas.•There was greater CO2 biofixation in the cultivation of microalgae with nanofibers. The aim of this study was to develop nanofibers containing nanoparticles with potential for the biological fixation of CO2 together with the microalgae Chlorella fusca LEB 111. An electrospinning technique was used for the production of polymeric nanofibers with different concentrations of iron oxide nanoparticles: 0, 2, 4, 6, 8, and 10% (w v−1). Nanofibers with a nanoparticle concentration of 4% (w v−1) were selected for use in the microalgal cultivation due to their smaller diameter (434 nm), high specific surface area (13.8 m2 g−1) and higher CO2 adsorption capacity (164.2 mg g−1). The microalgae C. fusca LEB 111 presented a higher CO2 biofixation rate of 216.2 mg L−1 d−1 when cultivated with these nanofibers. The results demonstrated the potential of electrospun nanofibers as physical adsorbents of CO2 since they can increase the contact time between the gas and the microorganism and consequently increase the CO2 biofixation by the microalgae.