**4. Conclusions**

A relatively simple method for the preparation of a photocatalyst was presented in which TiO2 was combined with carbon spheres, which were then deposited on a silica fiber cloth to provide a good bed for the photocatalytic reduction of CO2 in the gas phase. The obtained TiO2-carbon spheres/silica fiber photocatalysts showed high selectivity towards carbon monoxide. This is very promising from a practical point of view since the step of separating the carbon monoxide from the postreaction mixture can be avoided with only a slight reduction in the activity. For TiO2 combined with a higher amount of graphitic carbon spheres, the two-electron reduction of CO2 to CO is more privileged than an eight-electron reaction to methane.

**Author Contributions:** Conceptualization, A.W.M. and U.N.; methodology, A.W.M., E.K.-N., A.W. and K.C.; software, M.G.; validation, A.W.M., U.N., E.K.-N. and I.P.; formal analysis, K. ´ C., K.W., ´ E.E. and M.G.; investigation, A.W.M., K.C. and K.W.; resources, U.N.; data curation, A.W.M. and ´ U.N.; writing—original draft preparation, A.W.M. and K.C.; writing—review and editing, K. ´ C., ´ A.W.M., U.N., P.S. and D.S.; visualization, K.C.; supervision, A.W.M. and U.N.; project administration, ´ U.N.; funding acquisition, U.N. All authors have read and agreed to the published version of the manuscript.

**Funding:** The research leading to these results received funding from the Norway Grants 2014–2021 via the National Centre for Research and Development under the grant number NOR/POLNORCCS/ PhotoRed/0007/2019-00.

**Data Availability Statement:** Not applicable.

**Conflicts of Interest:** The authors declare no conflict of interest.
