Interface dipole modulation boosting plasmonic energy utilization for efficient photocatalytic hydrogen evolution

S-scheme heterojunction of polyfluorene derivatives coupled with ZnxCd1-xS nanoparticles for efficient and stable photocatalytic hydrogen evolution

We report the construction of a highly efficient noble metal free photocatalytic hydrogen (H2) evolution system using CdS quantum dots as the light absorber and metallic MoP as the cocatalyst. MoP can be prepared by a facile temperature programmed reduction method and small clusters of MoP nanoparticles sized 10-30 nm were obtained by probe ultrasonication. The effect of synthesis conditions on the electrocatalytic and photocatalytic H2 evolution activity of MoP was investigated. The highest H2 evolution rate of 1100 μmol h(-1) can be achieved by the optimized system under visible light (λ≥ 420 nm), which is comparable to that when Pt was used as the cocatalyst. A high quantum efficiency of 45% is obtained at 460 nm irradiation.

Efficient photocatalytic hydrogen evolution via interfacial engineering and charge carrier utilization with WSP/g-C3N4 S-scheme heterojunction

Fabrication of S-scheme Zn1-xCdxS/NiO heterojunction for efficient photocatalytic hydrogen evolution

A highly efficient photocatalytic hydrogen evolution system without an electron mediator such as methyl viologen (MV(2+)) has been constructed using 9-mesityl-10-methylacridinium ion (Acr(+)-Mes), poly(N-vinyl-2-pyrrolidone)-protected platinum nanoclusters (Pt-PVP) and NADH (beta-nicotinamide adenine dinucleotide, reduced form) as the photocatalyst, hydrogen evolution catalyst and electron donor, respectively. The photocatalyst (Acr(+)-Mes) undergoes photoinduced electron transfer (ET) from the Mes moiety to the singlet excited state of the Acr(+) moiety to produce an extremely long-lived ET state, which is capable of oxidizing NADH and reducing Pt-PVP, leading to efficient hydrogen evolution. The hydrogen evolution efficiency is 300 times higher than that in the presence of MV(2+) because of the much faster reduction rate of Pt-PVP by Acr(*)-Mes compared with that by MV(*+). When the electron donor (NADH) is replaced by ethanol in the presence of an alcohol dehydrogenase (ADH), NADH is regenerated during the photocatalytic hydrogen evolution.

Impaired wound healing is the most common and severe complication in diabetic patients. Here, we develop a new type of medical dressing for diabetic wound healing by using photocatalytic hydrogen evolution from semiconducting polymer dots (Pdots) under red-light irradiation. The Pdots consist of semiconducting polymer (PM6) and fullerene derivative (PCBM), forming a donor-acceptor heterojunction structure with efficient photocatalytic hydrogen evolution. The antioxidant capacity of the heterojunction Pdots by PM6:PCBM was characterized to be ∼2.5 times higher than that of the donor-acceptor Pdots species in previous studies. By directly loading the heterojunction Pdots into a sterile medical dressing, we show that the medical dressing effectively scavenges hydroxyl radicals in diabetic wounds, promotes the expression of anti-inflammatory cytokines, and accelerates wound healing under low-dose red-light illumination. We analyze immunofluorescence staining of the skin tissues and discovered the effect of hydrogen therapy on an inflammatory process such as macrophage polarization from M1 type to M2 type. This study highlights the efficient hydrogen generation from Pdot-loaded medical dressing, providing a new approach for treatment of diabetic wounds.

Highly efficient photocatalytic hydrogen evolution from water-soluble conjugated polyelectrolytes

Facile deposition of CoMoS4 on flower-like CdIn2S4 microspheres: Enhanced charge separation and efficient photocatalytic hydrogen evolution

In this paper, the new photocatalyst, Ptx-/TiO2-yBy was prepared by impregnation method via coupling with a inorganic water splitting system, namely, a ternary system K+,Na+/B4O72- - H2O for hydrogen evolution. The integration process of the preparation for B doping Pt/TiO2 with the significant photocatalytic hydrogen evolution in the ternary system K+,Mg2+/B4O72- - H2O and K+,Na+/B4O72- - H2O were accomplished by impregnation in situ. The photocatalyst Ptx-/TiO2-yBy synthesis and the photocatalytic hydrogen production of the isothermal solubility of the ternary system K+,Mg2+/B4O72- - H2O and K+,Na+/B4O72- - H2O at 25 ºC have been studied. Thus, the present challenge is not only to demonstrate a suitable photocatalytical system that can efficiently produce hydrogen under the borate exsited, but also research that the addition of borate to the suspensions greatly enhanced the stability of the photocatalysts over semiconductor catalysts.The results show that borate solution is a suitable for B doped TiO2 photocatalysts preparation and a novel photocatalyst Ptx-/TiO2-yBy was successfully prepared by this way. XRD and XPS characterization showed that both anatase and rutile are coexisted and the B is incorporated into the crystal of the TiO2.So the TiO2 can be denoted as TiO2-xBx. The effect of borate on the photocatalytic properties were investigated. The results showed that the amount of hydrogen evolved is enhanced by factors of 4 with the addition of H3BO3 to the ethanol/water reaction solutions. The role of boron anion does not act as a sacrificial electron donors. DOI: http://dx.doi.org/10.5755/j01.ms.20.4.6412

The noble-metal-free Ni2P/CTF composites for efficient photocatalytic hydrogen evolution under visible-light irradiation

Evolutionary mechanism of Ni-ZIF/CdS calcination for efficient photocatalytic hydrogen evolution

Donor–acceptor (D–A) polymers have shown great promise as photocatalysts for hydrogen evolution, benefiting from efficient exciton separation and charge mobility via their push‐pull electronic structure. However, despite advantages like cost‐effectiveness, synthetic accessibility, and well‐defined structures, D–A conjugated small molecules remain underexplored for photocatalytic applications. Herein, three novel D–A‐type fulvalene‐derived small molecules (F‐ID, F‐IC, and BF‐IC) are synthesized through systematic modulation of donor and acceptor units. Spectroscopic and theoretical investigations revealed that both the extended conjugation length of the donor unit and enhanced electron‐withdrawing capability of the acceptor unit can effectively broaden the light absorption range and reduces the optical bandgap. The optimized photocatalyst BF‐IC, exhibiting the most red‐shifted absorption and narrowest bandgap (consistent with DFT calculations), demonstrated superior photocatalytic performance with a hydrogen evolution rate of 13.43 ± 0.62 mmol h−1 g−1 using ascorbic acid as the sacrificial agent. To our knowledge, this work presents the first demonstration of highly efficient hydrogen evolution using a fulvalene‐derived D–A‐type small‐molecule photocatalyst. Our study not only establishes fulvalene‐based D–A systems as a promising new class of photocatalysts for solar‐to‐chemical energy conversion but also offers a rational molecular design strategy for high‐performance photocatalysts through structural modulation.

An all-organic TPA-3CN/2D-C3N4 heterostructure for high efficiency photocatalytic hydrogen evolution

Construction of Z-scheme heterostructure is of great significance for realizing efficient photocatalytic water splitting. However, the conscious modulation of Z-scheme charge transfer is still a great challenge. Herein, interfacial Mo-S bond and internal electric field modulated Z-scheme heterostructure composed by sulfur vacancies-rich ZnIn2S4 and MoSe2 was rationally fabricated for efficient photocatalytic hydrogen evolution. Systematic investigations reveal that Mo-S bond and internal electric field induce the Z-scheme charge transfer mechanism as confirmed by the surface photovoltage spectra, DMPO spin-trapping electron paramagnetic resonance spectra and density functional theory calculations. Under the intense synergy among the Mo-S bond, internal electric field and S-vacancies, the optimized photocatalyst exhibits high hydrogen evolution rate of 63.21 mmol∙g−1·h−1 with an apparent quantum yield of 76.48% at 420 nm monochromatic light, which is about 18.8-fold of the pristine ZIS. This work affords a useful inspiration on consciously modulating Z-scheme charge transfer by atomic-level interface control and internal electric field to signally promote the photocatalytic performance.

Construction of a transition-metal sulfide heterojunction photocatalyst driven by a built-in electric field for efficient hydrogen evolution under visible light