Self-Template-Derived Hollow Brookite TiO2@Na2Ti3O7–Ag 1D@2D-0D Nanoarchitectures with Amine Modification Promote Photocatalytic CO2 Reduction

Using amine-modified protonated titanate (NH2–H2Ti2O5·3H2O) as a template, surface reconstruction is carried out by hydrothermal treatment in the NaOH/ethylene glycol (EG)/H2O system, and finally, Ag nanoparticle-loaded 1D@2D TiO2@Na2Ti3O7 nanoarchitectures (TiO2@Na2Ti3O7–Ag) have been fabricated. The corresponding formation process is analyzed by using XRD, SEM, and EDX techniques. XPS and Fourier transform infrared (FT-IR) spectra confirm the presence of surface amino groups. Photo/electrochemical measurements indicate that the loading of Ag0 is beneficial for light absorption, charge separation, and transfer of 1D@2D TiO2@Na2Ti3O7 nanoarchitectures. The best CH4 and CO yields in the photocatalytic CO2 reduction test on the TiO2@Na2Ti3O7–Ag0.025 photocatalyst are 9.01 and 0.88 μmol/g/h, which are improved nearly 64 and 44 times, respectively. The generation of the *HCOO–, *CO, and *OCH3 intermediates corresponding to the reaction pathway is studied by in situ FT-IR. These findings could pave ways for the development of efficient photocatalytic CO2 conversion systems.