Ammonia NH₃ is a major and essential chemical for industrial and agricultural applications, and a precursor for almost all nitrogen-containing products. About 80% of the total ammonia produced globally is utilized for the production of fertilizers via oxidation to NO_x and nitrates. Today, the hydrogen and energy required comes mostly from natural gas, which renders the technology unsustainable and with large climate gas emissions. Fixation of dinitrogen is extremely challenging as the N≡N triple bond is very strong and difficult to activate due to the absence of a permanent dipole. In general, the reduction of nitrogen is difficult without a catalyst and require intensive energy inputs. The long-established ammonia synthesis method is the Haber-Bosch process, in which nitrogen and hydrogen react on a catalyst such as ruthenium and iron at high temperature (450-500°C) and high pressure (150-300 bar). The Haber–Bosch synthesis of ammonia is carried out on a large scale, and about 2 % of all energy consumed by mankind is utilized in this process. The process also releases hundreds of millions of tons of carbon dioxide to the atmosphere. It is desirable to have less energy demanding alternatives for capturing nitrogen and converting to ammonia. The most challenging step remains the scission of the strong N≡N bond (bond energy = 945 kJmol-1), for which we explore the use of artificial hard UV radiation (UV B, 315-280 nm and UV C, 280-100 nm, corresponding to 4.4-12.4 eV in energy).Previous studies (Schrauzer 1977) has shown that N2 can be converted to ammonia by using sunlight and TiO2 as photocatalyst however only very small amounts are detected.In the current project we aim to produce ammonia (or NO_x) from N₂ in air by utilizing sunlight (hard UV) and photocatalysts with optimized band edges and a large band gap. First we reproduce previous studies with TiO₂ -demonstrating that N₂, phototcatalyst and sunlight are all necessary components to produce ammonia. Then we aim to improve the production of ammonia by careful selection of phototcatalysts that fulfil the desired criterias. Several large band-gap materials has been screened as potential candidates for photofixation. Among these our main result show that Fe-doped SrTiO₃ produce NO_x (which can later be reduced to ammonia) at almost twice the rate of literature values (and our own reproduction) for TiO₂