The photocatalytic conversion of CO2 into valuable chemicals such as CO is a promising solution to mitigate both the health and environmental impact from green house gases. The photocatalytic field faces several challenges towards their industrial deployment under competitive scale. Several knowledge gaps exist in the design and understanding of photo-active materials mimicking the organic reactions catalysed by nature. The training tasks in PHOCAT, under the supervision of Prof. Arias (Host, EHU, Spain) and a 4-month secondment period with Prof. Ravelli (UNIP, Italy) will provide the researcher with new skills in chemical reaction engineering, material science and operando spectroscopy. PHOCAT will explore new chemical engineering concepts, related to photocatalyst design, catalysis, spectroscopy and engineering in order to enhance CO productivity from CO2 and H2O reactants. Specifically, PHOCAT will tailor the electronic and redox features in C3N4 materials, tested under unprecedented capillary solvation methods and operando synchrotron XAS. This scientific approach will contribute to design innovative photocatalytic process with potential industrial application. This MSCA-PF will certainly contribute the researcher to be trained in new scientific and transferable skills, enhancing the career perspectives to become an independent and mature researcher in the EU in the near future.