Abstract

Abstract Building artificial carbon cycling systems for the direct conversion of wastewater into value‐added solar fuels using renewable solar energy can contribute to achieving carbon neutrality. Herein, a bifunctional photocatalyst comprising three‐dimensionally ordered Ti 3 C 2 T x /TiO 2 nanoflowers is exploited for tandem carbon cycling systems to achieve efficient organic wastewater treatment with simultaneous CO 2 resourcing. The highest efficiency is achieved by using the optimal Ti 3 C 2 T x /TiO 2 photocatalyst to treat simulated wastewater containing rhodamine B (RhB), with an enhanced primary CO production rate of 10.02 µmol g −1 h −1 and RhB degradation efficiency of 77.6% after 1 h of illumination in an anoxic environment. The CO/H 2 ratio of the produced syngas can be readily tuned from 0.95 to 1.86 by adjusting the Ti 3 C 2 T x content. Mechanistic studies based on DFT, in situ DRIFTS, and LC‐MS 2 /IC reveal that the coupled photocatalytic RhB degradation and CO 2 reduction processes collectively undertake *HCOO intermediate coverage. This phenomenon triggers the sustainable and simultaneous conversion of *CO 2 and *HCOO into CO under mild conditions and crosses the key rate‐limiting step of CO 2 ‐to‐CO conversion, thereby achieving overall carbon utilization from organic wastewater treatment. This study offers in‐depth insights into the design and mechanisms of highly effective carbon utilization in artificial carbon cycling systems.