Unraveling the Roles of Hot Electrons and Cocatalyst toward Broad Spectrum Photocatalytic H₂ Generation of g‐C₃N₄ Nanotube

Abstract

Exploiting active photocatalysts with broad spectrum light response is a priority target in the field of photocatalysis. Herein, integrating Au and CoO nanoparticles with g‐C3N4 hollow nanotubes, a promising ternary photocatalyst with wide‐light spectrum response (420–650 nm) is designed, in which Au nanoparticles play the dual role of plasmonic electron donor and reduction cocatalyst, while CoO nanoparticles act as oxidation cocatalyst. The optimum H2 evolution rates of the ternary hybrid reach 238.7 and 4.9 μmol under the irradiation of visible light and monochromic light of 650 nm, respectively. Localized surface plasmon resonance (LSPR) can promote charge‐carrier generation in the g‐C3N4, and the appropriate band alignment between the Au and g‐C3N4 is favorable for hot electron transfer from Au to g‐C3N4, which makes this ternary hybrid possess extra hot electrons for water reduction reaction under a wider solar spectrum. Furthermore, Au as a reduction cocatalyst and CoO as an oxidation cocatalyst can effectively impel the charge separation and restrain charge recombination, which is also responsible for the enhanced photocatalytic activity. This work affords a credible strategy for the rational construction of plasmon‐assisted photocatalysts for the wider‐spectrum appliance of solar energy.

Construction of UiO-66/Bi4O5Br2 Type-II Heterojunction to Boost Charge Transfer for Promoting Photocatalytic CO2 Reduction Performance

“…The charge separation behavior was investigated to explore the reason for the enhanced photocatalytic CO 2 reduction performance. Figure 5A displays that the intensity of transient photocurrent of the UiO-66 is very low, while the U@B-10 composite demonstrates the highest transient photocurrent density compared to that of the UiO-66 and Bi 4 O 5 Br 2 , indicating that the U@B-10 composite owns the fastest separation efficiency of photogenerated carriers ( Liu et al, 2020b ; Liu et al, 2020c ). The EIS was also used to characterize the interface charge carrier transport capacity.…”

Tailor‐Engineered 2D Cocatalysts: Harnessing Electron–Hole Redox Center of 2D g‐C3N4 Photocatalysts toward Solar‐to‐Chemical Conversion and Environmental Purification

“…Secondly, apart from the common electron doping, other advanced modification techniques should be widely employed to further increase the photocatalytic efficiency of 2D/2D cocatalyst/g-C 3 N 4 hybrids such as the facet and defect engineering, [289] localized plasmonic-decoration technique, [290] single-atom catalysis, [291] broadening light spectrum, [292] piezophototronic effect, [293] and photothermal catalysis. [294] For instance, photo-thermal catalysis with the capability of harvesting low-energy infrared photons has gained tremendous attention as it can generate energetic hot electrons that can induce a thermal effect on the surroundings.…”

Highly crystalline sulfur and oxygen co-doped g-C3N4 nanosheets as an advanced photocatalyst for efficient hydrogen generation

“…41 In comparison with SOCNB (absorption edge of 530 nm), the absorption of SOCNS shows an obvious blue shift, presumably due to the nanoconfinement effect. 21,22 The band gap energies of the asprepared samples are shown in Fig. 3c.…”

“…[14][15][16] Therefore, it is urgent to develop a modified g-C 3 N 4 photocatalyst for improving the conversion efficiency of solar energy to chemical energy. So far, a variety of effective strategies, including heterojunction fabrication, [17][18][19] morphology tailoring, [20][21][22] and heteroatom doping, [23][24][25] have been developed to promote the photocatalytic hydrogen production of g-C 3 N 4 . Among all the doping elements, nonmetal oxygen doped g-C 3 N 4 is one of the effective ways to extend the visible-light absorption and regulate the intrinsic electronic characteristics and band structure of g-C 3 N 4 , thereby leading to an enhancement of its photocatalytic activities.…”