Photocatalysis: Effective Prevention of Charge Trapping in Graphitic Carbon Nitride with Nanosized Red Phosphorus Modification for Superior Photo(electro)catalysis (Adv. Funct. Mater. 46/2017)

Abstract

In article number https://doi.org/10.1002/adfm.201703484 Jimmy C. Yu and co‐workers report how adding red P nanoparticles onto g‐C3N4 effectively suppresses charge trapping and thus prolongs the lifetime of active charges in the photocatalyst. The optimized red P/g‐C3N4 composite exhibits a very high photocatalytic hydrogen evolution rate of 2565 μmol h−1 g−1. The charge trapping/de‐trapping processes are thoroughly investigated by time‐resolved transient absorption spectroscopy.

Unveiling the role of a ground state charge transfer complex in carbon nanoparticles for highly efficient metal-free solar hydrogen production

“…The signicant enhancement in the lifetime upon complex formation between N, P-CNPs and TEOA suggests the formation of long-lived free carriers. 40,41 Therefore, the fundamental absorption and photoluminescence studies mentioned above are convincing enough to support the formation of a stable, long-lived charge-transfer state between N, P-CNPs and TEOA.…”

“…The high and stable photocurrent density of N, P-CNPs (TEOA) provides further evidence for the increased photoinduced free carrier and charge separation, promoting the photocatalytic hydrogen evolution activities. 41,60 The anodic photocurrent nature and the positive slope in the Mott-Schottky analysis collectively depict (Fig. 6(d) and 4(c)) the n-type characteristics of both N, P-CNPs and N, P-CNPs (TEOA).…”

Directional and Ultrafast Charge Transfer in Oxygen‐Vacancy‐Rich ZnO@Single‐Atom Cobalt Core‐Shell Junction for Photo‐Fenton‐Like Reaction

“…The femtosecond (fs) TAS were performed upon 360 nm pulse pump and a white‐light pulse (390–680 nm) probe. As illustrated in Figure 2E and F, all fs‐TA spectra show broad negative absorption signals, owing to stimulated emission and bleaching of the ground state [38] . The intensity of TA signals was increased very fast within few ps after photoexcitation and then gradually decayed (≈2 ns), which can be interpreted as the instantaneous generation of charge carriers and recombination of electron‐hole pairs, respectively [39] .…”

Bottom‐Up Strategy to Enhance Long‐Range Order of Poly(Heptazine Imide) Nanorods for Efficient Photocatalytic CO 2 Methanation

“…The short lifetime (τ 1 ) corresponds to a rapid recombination of charges from the excited state back to the ground state, while the long lifetime (τ 2 ) reflects an obviously slow recombination of inactive charges stuck in the deep trap states. [30] Compared with P-PHI, the lifetime of long-lived charges of U2-PHI is much shorter (1608.7 ps vs. 979.9 ps) and the corresponding percentage is significantly decreased (26.7 % vs. 7.1 %), reflecting an accelerated detrapping process derived from decreased defects. The above results confirm that the improved long-range order promotes the separation and transfer of photogenerated carriers.…”