Fabricating\na CNIS@SL S‑Scheme Heterojunction\nwith Spatial Charge Separation for Boosting Photocatalytic Biomass\nReforming

Cooperative\ncoupling of energy fuel production with high-value\norganic acid synthesis is promising in photocatalytic reforming. Nonetheless,\nthere are few reports on the enhancement of biomass conversion with\nan S-scheme heterojunction. Herein, we have employed a bottom-up strategy\nto develop a nonprecious metal S-scheme heterojunction (CNIS@SL) for\nefficiently converting hemicellulose-derived feedstocks into CO and\nxylonic acid. Under the synergistic effects of Ni element doping,\nan S-scheme heterojunction, and a biochar network, this system achieved\na CO release rate of 1130.0 μmol g<sup>–1</sup> h<sup>–1</sup> and 62.4% of xylonic acid. Electron spin resonance\nanalysis, supplemented by poisoning tests, identified holes (h<sup>+</sup>) as the predominant active species in the reaction mechanism.\nIn situ irradiation X-ray photoelectron spectroscopy further confirmed\nthat electrons transfer directly from the conduction band of the CIS\nto the valence band of NIS under the action of an internal electric\nfield. These findings offer fresh perspectives on designing an S-scheme\nheterojunction for highly efficient biomass reforming.