Boosting photocatalytic hydrogen evolution of g-C3N4 catalyst via lowering the Fermi level of co-catalyst

Metal Halide Perovskite Based Heterojunction Photocatalysts

“…In general, the Fermi energy (E f ) of conductors, such as Pt, Au, Pd, and carbon materials, is located about 0.5-1.0 eV versus the reversible hydrogen electrode (RHE), which is relatively positive compared to that of MHPs (< 0.5 eV vs RHE). [16,[23][24][25][26][27][28] After contact, an upward band bending at the MHP-conductor interface as a consequence of the band alignment results in the formation of a Schottky barrier (Figure 2A). [29][30][31][32][33] Note, band bending is a concept that is well described for bulk semiconductors, [34] the width over which bands bend generally is several hundreds of nanometers and decreases as the particle size decreases.…”

“…In general, the Fermi energy ( E f ) of conductors, such as Pt, Au, Pd, and carbon materials, is located about 0.5–1.0 eV versus the reversible hydrogen electrode (RHE), which is relatively positive compared to that of MHPs (<0.5 eV vs RHE) [16, 23–28] . After contact, an upward band bending at the MHP–conductor interface as a consequence of the band alignment results in the formation of a Schottky barrier (Figure 2A) [29–33] .…”

Point‐to‐face contact heterojunctions: Interfacial design of 0D nanomaterials on 2D g‐C3N4 towards photocatalytic energy applications

“…(D) Schematic illustration of the photocatalytic HER mechanism of Pt/g‐C 3 N 4 and Pt 3 Co/g‐C 3 N 4 in terms of energy band diagrams and the surface reduction reaction mechanism. Reproduced with permission: Copyright 2021, Springer 320 . (E) The free‐energy diagram for H 2 O dissociation and H* adsorption potential on the surface of Pt (111) and Pt 3 Co (111).…”

“…(E) The free‐energy diagram for H 2 O dissociation and H* adsorption potential on the surface of Pt (111) and Pt 3 Co (111). Reproduced with permission: Copyright 2021, Springer 320 . (F) EPR spectra of DMPO−•OH in aqueous dispersions of g‐C 3 N 4 , TiO 2 , and TiO 2 /g‐C 3 N 4 .…”

“…The reduced d ‐band center contributed electrons to the Pd antibonding orbital and minimized surface adsorption, and enhanced the photoinduced electron storage ability, thus further improving HER activity. By modifying the behavior of photoinduced charge carriers, Cai et al 320 loaded 0D Pt 3 Co cocatalysts onto g‐C 3 N 4 with good electron‐trapping ability owing to their low Fermi level, which allowed a higher degree of band bending than monometallic Pt NPs (Figure 20D). Concurrently, Pt 3 Co NPs were found to more easily dissociate H 2 O as compared to Pt (0.89 eV) because Pt 3 Co had a lower water dissociation energy barrier $$(\unicode{x02206}{G}_{({{\rm{H}}}_{2}{\rm{O}})})$$ of 0.35 eV (Figure 20E), which led to rapid surface reaction kinetics.…”