Ni-phyllosilicate nanotubes coated by CeO₂ for ultra-efficiency of 36.9% and near-limit CO₂ conversion in solar-driven conversion of CO₂-to-fuel

Solar-driven CO₂ reduction by methane (CRM) into valuable syngas not only mitigates greenhouse gases but also provides high-value syngas. However, it is still a daunting challenge to achieve high solar-to-fuel efficiency and good durability simultaneously. Here, a novel strategy of direct photothermocatalytic CO₂ is proposed based on a unique nanocomposite of ceria coated Ni-phyllosilicate nanotubes (Ni-psnts@CeO₂). A record-high solar-to-fuel efficiency (36.9 %) with very high production rates of H₂ and CO (120.90 and 136.84 mmol g_cat min⁻¹) and high CO₂ conversion rate (90.4 %) close to thermodynamic limit are demonstrated. Excellent long-term durability is achieved due to its extremely low carbon deposition rate of 1.3 × 10⁻⁴ g_c g_cat h⁻¹ under focused UV–vis-IR irradiation for 100 h. These high performances are partially attributed to the active involving of lattice oxygen and oxygen vacancies from ceria in carbon gasification and CO₂ activation, which are confirmed by ¹⁸O isotope labeling and In-situ DRIFTS measurements. In addition, decreased activation energy enabled via photoactivation effects from photoexcited hot electrons also benefits high activities under direct light illumination. This work offers novel approaches for highly efficient and stable solar-driven CO₂-to-fuel conversion.