Generating Site Saturation Mutagenesis Libraries and Transferring Them to Broad Host-Range Plasmids Using Golden Gate Cloning.

Protein engineering is an established method for tailoring enzymatic reactivity. A commonly used method is directed evolution, where the mutagenesis and natural selection process is mimicked and accelerated in the laboratory. Here, we describe a reliable method for generating saturation mutagenesis libraries by Golden Gate cloning in a broad host range plasmid containing the pBBR1 replicon. The applicability is demonstrated by generating a mutant library of the iron nitrogenase gene cluster (anfHDGK) of Rhodobacter capsulatus, which is subsequently screened for the improved formation of molecular hydrogen.

Synchronous optimization of H2O and H adsorption on NiO1-xTex nanodots for alkaline photocatalytic H2 evolution.

Suitable H2O and H adsorption on the surface of transition metal chalcogenide cocatalyst is highly required to achieve their excellent alkaline H2-evolution rate. However, the weak adsorption of H2O and H atoms on NiTe surface greatly hinders its alkaline H2-evolution efficiency. Herein, an electron-deficient modulation strategy is proposed to synchronously improve the adsorption of H2O and H atoms on NiTe surface, which can greatly improve the alkaline photocatalytic H2 evolution of TiO2. In this case, highly electronegative oxygen atoms are introduced into the NiTe cocatalysts to induce the formation of electron-deficient Niδ+ and Teδ+ sites in the ultra-small-sized NiO1-xTex nanodots (0.5-2 nm), which can be uniformly loaded onto the TiO2 surface to prepare the NiO1-xTex/TiO2 photocatalysts by a facile complexation-photodeposition strategy. The resulting NiO1-xTex/TiO2 (0.6:0.4) photocatalyst exhibits the optimal activity (2143.36 µmol g-1 h-1), surpassing the activity levels of TiO2 and NiTe/TiO2 samples by 42.3 and 1.8 times, respectively. The experimental and theoretical investigations have revealed that the presence of highly electronegative O atoms in the NiO1-xTex cocatalyst can redistribute the charges of Ni and Te atoms for the formation of electron-deficient Niδ+ and Teδ+ active sites, thereby synchronously enhancing the adsorption of H2O on Niδ+ sites and H on Teδ+ sites and promoting alkaline photocatalytic H2 evolution. The current research about the synchronous optimization of the H2O and H adsorption offers a significant approach to design high-performance H2-evolution materials.

Dipole field as charge-transfer bridge between Cu atomic clusters/PtCu alloy nanocubes and nitrogen-rich C3N5 for superior photocatalytic hydrogen evolution.

Utilizing spontaneous polarization field to harness charge transfer kinetics is a promising strategy to boost photocatalytic performance. Herein, a novel Cu atom clusters/PtCu alloy nanocubes coloaded on nitrogen-rich triazole-based C3N5 (PtCu-C3N5) with dipole field was constructed through facile photo-deposition and impregnation method. The dipole field-drive spontaneous polarization in C3N5 acts as a charge-transfer bridge to promote directional electron migration from C3N5 to Cu atom clusters/PtCu alloy. Through the synergistic effects between Cu atom clusters, PtCu alloy and dipole field in C3N5, the optimized Pt2Cu3-C3N5 achieved a record-high performance with H2 formation rate of 4090.4 µmol g-1 h-1 under visible light, about 154.4-fold increase compared with pristine C3N5 (26.5 µmol g-1 h-1). Moreover, the apparent quantum efficiency was up to 25.33 % at 320 nm, which is greatly superior than most previous related-works. The directional charge transfer mechanism was analyzed in detail through various characterizations and DFT calculations. This work offers a novel pathway to construct high-efficiency multi-metal photocatalysts for solar energy conversion.

Naphthalene Monoanhydride and Perylene Composites for Efficient Photocatalytic Hydrogen Evolution and Metal-Free Heterogeneous Oxidative Amidation.

This study explores the synthesis of two visible light active organic chromophore-based composites using naphthalene monoanhydride (Np) and 1,7-dibromoperylene monoanhydride diester (PMDE). These chromophores feature favorable optical and electronic properties and polyaromatic skeletons with anhydride functionalities that facilitate π-π interactions between the chromophore and polymeric carbon nitride (CN) or covalent connections of chromophores with NH2 groups of CN. Accordingly, heterogeneous chromophore-CN composite photocatalysts namely, Np/CN(c) and PMDE/CN(c) were prepared by adopting in situ calcination (c) and composites Np/CN(a) and PMDE/CN(a) were prepared by ex situ physical adsorption (a) methods. In situ prepared Np/CN(c) and PMDE/CN(c) composites exhibited H2 evolution rates (HER) of 1069 and 705 µmol h-1 g-1, respectively, which are significantly higher than ex situ Np/CN(a) and PMDE/CN(a) composites with HER of 465 and 252 µmol h-1 g-1, respectively. These rates are 10, 7, 4.8, and 2.5 times higher than the bulk-CN, indicating the potential of these composites for efficient photocatalytic H2 evolution. Surface area normalized HER enhancements were 3.8, 5.3, 6.6, and 4.2 times higher for Np/CN(c), PMDE/CN(c), Np/CN(a), and PMDE/CN(a) respectively compared to bulk-CN. These composite photocatalysts exhibited excellent stabilities under prolonged photoirradiation, with H2 evolution consistently increasing with the light exposure time. Additionally, these metal-free heterogeneous composites demonstrated efficient photocatalytic activities towards oxidative amidation of aromatic aldehydes, with up to 80% product yields, establishing the prospects of combining homogeneous and heterogeneous entities in a metal-free active material in solar energy harvesting.

Promoting Charge-Carriers Dynamics by Relaxed Lattice Strain in A-site-doped Halide Perovskite for Photocatalytic H2 Evolution.

Because of the unique and superior optoelectronic properties, metal halide perovskites (MHPs) have attracted great interests in photocatalysis. Element doping strategy is adopted to modify perovskite materials to improve their photocatalytic performance. However, the contribution of bare doping-site onto photocatalytic efficiency, and the correlation between doping locations and activity have not yet to be demonstrated. This promoted us to explore the potential of A-site-doped MHPs for photocatalysis. Herein, we dope potassium (K+) into CsPbBr3 and first reveal that the occupied locations of K+ in CsPbBr3 is lattice incorporation rather than surface segregation, which would change from A-site substitution to interstitial site in lattice with the increase of K+ concentrations. Taking H2 evolution as a model reaction, photocatalytic activity of CsPbBr3 after K+ doping could be significantly improved ~11-fold with A-site substitution, which is superior to that of interstitial site doping. Moreover, other alkali metals including Li, Na, and Rb doping give the same results. The structure of photocatalysts during reaction confirmed the contribution of A-site doping onto enhanced photocatalytic activity. Mechanistic insights show it is a result of the relaxed residual lattice strain induced promoted charge-carriers dynamics and formed upward shifting of band after K+ A-site doping.

Chiral Pd(II) Nanofiber Promoting Electron Transfer of g-C3N4 for Efficient Photocatalytic Hydrogen Production.

The rapid transfer and separation of photogenerated electrons is very important for the improvement of photocatalytic efficiency. Here, chiral induced spin selectivity effect (CISS effect) was developed to accelerate electron transfer for efficient photocatalytic hydrogen production. A chiral and achiral racemic supramolecular Pd(II) complex nanofiber was fabricated via supramolecular self-assembly of chiral L-Py or its racemes with Pd(II) and used to modify carbon nitride (g-C3N4). The obtained chiral photocatalyst L-Py-Pd/g-C3N4-4 and achiral photocatalyst Rac-Pd/g-C3N4-4, show enhanced photocatalytic activities with hydrogen evolution rates of 2476 and 1339 µmol g-1 h-1, respectively, while that of pure g-C3N4 is 30.5 µmol g-1 h-1. Chiral photocatalyst has 85 % higher activity than achiral one and is 82.5-fold of pure g-C3N4, due to better suppression of the recombination of photogenerated electron-hole pairs in the interface of g-C3N4 contact with chiral molecule. Spectral tests and photoelectrochemical tests proved that the chiral supramolecular Pd(II) complex can act both as an electron spin filter and hydrogen reduction catalytic center to enhance photocatalytic efficiency. This work offers a new route to facilitate electron transfer by the CISS effect for photocatalytic hydrogen evolution.

Enhanced Photothermal-Assisted Hydrogen Production via a Porous Carbon@MoS2/ZnIn2S4 Type II-S-Scheme Tandem Heterostructure.

MoS2/ZnIn2S4 flower-like heterostructures into porous carbon (PC@MoS2/ZIS) are embedded. This ternary heterostructure demonstrates enhanced light absorption across a broad spectral range from 200 to 2500 nm. It features both Type-II and S-scheme dual heterojunction interfaces, which facilitate the generation, separation, and transfer of photoinduced carriers. The PC enveloped by MoS2/ZIS composite microspheres serves as a photothermal source, providing additional energy to the carriers. This process accelerates charge separation and migration, enhancing photothermal-assisted photocatalytic H2 evolution. The optimal H2 evolution rate for PC@MoS2/ZIS reaches an impressive 18.79 mmol g-1 h-1, with an apparent quantum efficiency of 14.1% at 400 nm. This work presents a promising approach for effectively integrating multicomponent heterostructures with photothermal effects, offering innovative strategies for efficient solar energy utilization and conversion.

Small Molecule π-π Stacking Promotes Efficient Photoelectrocatalytic Splitting of Aqueous Hydrogen Production from Polyaniline.

Photoelectrocatalysis efficiency depends on light absorption and the effective use of photogenerated carriers but is often limited by inefficient charge transfer and catalytic surface reactivity. In this study, π-π stacking of polar small molecules on aromatic ring-rich polyaniline (PANI) was carried out to improve its photoelectrocatalytic splitting of water for hydrogen production. Detailed photoelectrochemical experiments and density-functional theory (DFT) calculations show that small molecules of p-aminobenzoic acid (PABA) and PANI have the best π-π stacking (compared to p-toluenesulfonic acid (PTA)), which promotes the separation of carriers on the PANI surface. In addition, the polar effect of the small molecules also improves the reactivity of the PANI surface and also reduces the potential barrier for H2 evolution. The current density of PANI-PABA reached -0.12 mA/cm2 (1.23 V vs. RHE) 2.53 times higher than that of pure PANI in linear voltammetric scanning tests under light. This strategy of introducing polar small molecules into organocatalysts via π-π stacking will provide new ideas for the preparation of efficient organic photoelectrocatalysis.

Limiting Molecular Twisting: Upgrading a Donor-Acceptor Dye to Drive H2 Evolution.

The donor-acceptor (D-A) dye 4-(bis-4-(5-(2,2-dicyano-vinyl)-thiophene-2-yl)-phenyl-amino)-benzoic acid (P1) has been frequently used to functionalize NiO photocathodes and induce photoelectrochemical reduction of protons when coupled to a suitable catalyst. Photoinduced twisting of the P1 dye is steered on NiO by co-adsorption of tetradecanoic acid (C14, myristic acid (MA)). Density Functional Theory and time-resolved photoluminescence studies confirm that twisting lowers the energy levels of the photoexcited D-A dye. The apolar environment provided by the MA suppresses photoinduced D-A twisting, retards charge recombination following photoinduced charge separation between P1 and NiO, and provides a larger electrochemical potential increasing the photocurrent. Very interestingly, co-adsorption of MA induces H2 evolution upon photoexcitation without the presence of an H2 evolution catalyst. Based on prior art, the formation of H2 is assigned to the dissolution of Ni2+, followed by reduction and re-deposition of Ni nanoparticles acting as the catalytically active site. It propose that only excited P1 with suppressed twisting provides the sufficient electrochemical potential to induce deposition of Ni nanoparticles. The work illustrates the importance of understanding the effects of photoinduced intramolecular twisting and highlights the promise of designing twisting-limited D-A dyes to create efficient solar fuel devices.

Electrostatic Self-Assembly of CdS Quantum Dots with Co9S8 Hollow Nanotubes for Enhanced Visible Light Photocatalytic H2 Production.

CdS quantum dots (CdS QDs) are regarded as a promising photocatalyst due to their remarkable response to visible light and suitable placement of conduction bands and valence bands. However, the problem of photocorrosion severely restricts their application. Herein, the CdS QDs-Co9S8 hollow nanotube composite photocatalyst has been successfully prepared by loading Co9S8 nanotubes onto CdS QDs through an electrostatic self-assembly method. The experimental results show that the introduction of Co9S8 cocatalyst can form a stable structure with CdS QDs, and can effectively avoid the photocorrosion of CdS QDs. Compared with blank CdS QDs, the CdS QDs-Co9S8 composite exhibits obviously better photocatalytic hydrogen evolution performance. In particular, CdS QDs loaded with 30% Co9S8 (CdS QDs-30%Co9S8) demonstrate the best photocatalytic performance, and the H2 production rate reaches 9642.7 µmol·g-1·h-1, which is 60.3 times that of the blank CdS QDs. A series of characterizations confirm that the growth of CdS QDs on Co9S8 nanotubes effectively facilitates the separation and migration of photogenerated carriers, thereby improving the photocatalytic hydrogen production properties of the composite. We expect that this work will facilitate the rational design of CdS-based photocatalysts, thereby enabling the development of more low-cost, high-efficiency and high-stability composites for photocatalysis.

Synergistic effect of interstitial phosphorus doping and MoS2 modification over Zn0.3Cd0.7S for efficient photocatalytic H2 production.

ZnxCd1-xS photocatalysts have been widely investigated due to their diverse morphologies, suitable band gaps/band edge positions, and high electronic mobility. However, the sluggish charge separation and severe charge recombination impede the application of ZnxCd1-xS for hydrogen evolution reaction (HER). Herein, doping of phosphorus (P) atoms into Zn0.3Cd0.7S has been implemented to elevate S vacancies concentration as well as tune its Fermi level to be located near the impurity level of S vacancies, prolonging the lifetime of photogenerated electrons. Moreover, P doping induces a hybridized state in the bandgap, leading to an imbalanced charge distribution and a localized built-in electric field for effective separation of photogenerated charge carriers. Further construction of intimate heterojunctions between P-Zn0.3Cd0.7S and MoS2 accelerates surface redox reaction. Benefiting from the above merits, 1 % MoS2/P-Zn0.3Cd0.7S exhibits a high hydrogen production rate of 30.65 mmol·g-1·h-1 with AQE of 22.22 % under monochromatic light at 370 nm, exceeding most ZnxCd1-xS based photocatalysts reported so far. This work opens avenues to fabricate examplary photocatalysts for solar energy conversion and beyond.

Dual-Vacancy-Engineered ZnIn2S4 Nanosheets for Harnessing Low-Frequency Vibration Induced Piezoelectric Polarization Coupled with Static Dipole Field to Enhance Photocatalytic H2 Evolution.

This study investigates the impact of In- and S-vacancy concentrations on the photocatalytic activity of non-centrosymmetric zinc indium sulfide (ZIS) nanosheets for the hydrogen evolution reaction (HER). A positive correlation between the concentrations of dual In and S vacancies and the photocatalytic HER rate over ZIS nanosheets is observed. The piezoelectric polarization, stimulated by low-frequency vortex vibration to ensure the well-dispersion of ZIS nanosheets in solution, plays a crucial role in enhancing photocatalytic HER over the dual-vacancy engineered ZIS nanosheets. The piezoelectric characteristic of the defective ZIS nanosheets is confirmed through the piezopotential response measured using piezoelectric force microscopy. Piezophotocatalytic H2 evolution over the ZIS nanosheets is boosted under accelerated vortex vibrations. The research explores how vacancies alter ZIS's dipole moment and piezoelectric properties, thereby increasing electric potential gradient and improving charge-separation efficiency, through multi-scale simulations, including Density Functional Theory and Finite Element Analysis, and a machine-learning interatomic potential for defect identification. Increased In and S vacancies lead to higher electric potential gradients in ZIS along [100] and [010] directions, attributing to dipole moment and the piezoelectric effect. This research provides a comprehensive exploration of vacancy engineering in ZIS nanosheets, leveraging the piezopotential and dipole field to enhance photocatalytic performances.

Ultraviolet-Visible-near infrared induced photocatalytic H2 evolution over S-scheme Cu2-xSe/ZnSe heterojunction with surface plasma effects.

Localized surface plasmon resonance (LSPR) effect plays a crucial role in the field of solar energy utilization. In this work, we successfully prepared a Cu2-xSe/ZnSe S-scheme heterojunction with a broad-spectrum response using the hot-injection and low-temperature water bath method. Importantly, we demonstrated that the photothermal effect induced by the LSPR of nonstoichiometric Cu2-xSe can significantly improve the slow kinetics of water splitting, resulting in an apparent activation energy reduction from 50.1 to 28.7 kJ·mol-1. This improvement is responsible for achieving the highest photocatalytic H2 evolution rate of 63.6 mmol·g-1·h-1 over 2.7 % Cu2-xSe/ZnSe under the wavelength ranged from 200 to 2500 nm, which is 3.4 and 5.6 times higher than that of ZnSe and Cu2-xSe, respectively. Furthermore, the composite exhibits a remarkable H2 production rate of 0.108 mmol·g-1·h-1 under near-infrared spectroscopy (800<λ<2500 nm), while ZnSe shows limited capability in H2 releasing. Additionally, Cu2-xSe/ZnSe demonstrates distinct photocurrent response when λ > 800 nm. The enhanced performance in H2 evolution can be attributed to the synergistic effect of LSPR-induced light absorption and S-scheme heterojunction, which not only expands the light absorption range to the near-infrared region but also facilitates hot electron injection, charge carrier separation and transfer, leading to a faster surface reaction kinetics. This study provides an effective approach for designing a broad-spectrum light responsive non-precious metal-based photothermal-assisted photocatalytic system.

Structural Distortion of g-C3N4 Induced by a Schiff Base Reaction for Efficient Photocatalytic H2 Evolution.

Photocatalytic H2 evolution by water splitting is a promising approach to address the challenges of environmental pollution and energy scarcity. Graphitic carbon nitride (g-C3N4) has emerged as a star photocatalyst because of its numerous advantages. To address the limitations of traditional g-C3N4, namely its inadequate visible light response and rapid recombination of photogenerated carriers, we employed a schiff base reaction to synthesize -C=N- doped g-C3N4. The introduction of -C=N- groups at the bridging nitrogen sites induced structural distortion in g-C3N4, facilitating n-π* electronic transitions from the lone pair electrons of nitrogen atom and extending light absorption up to 600 nm. Moreover, the presence of heterogeneous π-conjugated electron distribution effectively traps photogenerated electrons and enhances charge carrier separation. Benefiting from its expanded spectral response range, unique electronic properties, increased specific surface area, the doped g-C3N4 exhibited outstanding photocatalytic H2 evolution performance of 1050.13 µmol/g/h. The value was 5.9 times greater than the pristine g-C3N4.

3D/3D Bamboo Charcoal/Bi2WO6 Bifunctional Photocatalyst for Degradation of Organic Pollutants and Efficient H2 Evolution Coupling with Furfuryl Alcohols Oxidation.

Photocatalysis is one of the most promising pathways to relieve the environmental contamination caused by the rapid development of modern technology. In this work, we demonstrate a green manufacturing process for the 3D/3D rod-shaped bamboo charcoal/Bi2WO6 photocatalyst (210BC-BWO) by controlled carbonization temperature. A series of morphology characterization and properties investigations (XRD, SEM, UV-vis DRS, transient photocurrent response, N2 absorption-desorption isotherms) indicate a 210BC-BWO photocatalyst with higher charge separation efficiency, larger surface area, and better adsorption capacity. The excellent photocatalytic performance was evaluated by degrading rhodamine B (RhB) (98.5%), tetracycline hydrochloride (TC-HCl) (77.1%), and H2 evolution (2833 µmol·g-1·h-1) coupled with furfuryl alcohol oxidation (3097 µmol·g-1·h-1) under visible light irradiation. In addition, the possible mechanisms for degradation of organic pollutants, H2 evolution, and furfuryl alcohol oxidation were schematically investigated, which make it possible to exert photocatalysis by increasing the active radical. This study shows that the combination of bamboo charcoal and bismuth tungstate can be a powerful photocatalyst that rationally combines H2 evolution coupled with furfuryl alcohol oxidation and degradation of pollutants.

A Schottky/Z-Scheme Hybrid for Augmented Photocatalytic H2 and H2O2 Production.

The prodigious employment of fossil fuels to conquer the global energy demand is becoming a dreadful threat to the human society. This predicament is appealing for a potent photocatalyst that can generate alternate energy sources via solar to chemical energy conversion. With this interest, we have fabricated a ternary heterostructure of Ti3C2 nanosheet modified g-C3N4/Bi2O3 (MCNRBO) Z-scheme photocatalyst through self-assembly process. The morphological analysis clearly evidenced the close interfacial interaction between g-C3N4 nanorod, Bi2O3 and Ti3C2 nanosheets. The oxygen vacancy created on Bi2O3 surface, as suggested by XPS and EPR analysis, supported the Z-scheme heterojunction formation between g-C3N4 nanorod and Bi2O3 nanosheets. The collaborative effect of Z-scheme and Schottky junction significantly reduced charge transfer resistance promoting separation efficiency of excitons as indicated from PL and EIS analysis. The potential of MCNRBO towards photocatalytic application was investigated by H2O2 and H2 evolution reaction. A superior photocatalytic H2O2 and H2 production rate for MCNRBO is observed, which are respectively around 5 and 18 folds higher as compared to pristine CNR nanorod. The present work encourages for the development of a noble, eco-benign and immensely efficient dual heterojunction based photocatalyst, which can acts as saviour of human society from energy crisis.

Correlation between existential form of ruthenium cocatalyst and photocatalytic hydrogen evolution of carbon nitride.

Catalysts composed of nanocluster and single-atom (SA) were extensively used to enhance electrocatalytic water splitting performance, whereas study of their photocatalytic hydrogen (H2) evolution activity was limited. Herein, carbon nitride (CN) decorated by ruthenium (Ru) cocatalysts existed as SA + cluster, cluster + nanoparticles (NPs), and NPs were prepared by impregnation and calcination processes. The correlation between existential form, content of Ru cocatalyst and H2 evolution rate were carefully discussed. It was found that Ru NPs were favor for water molecule adsorption, whereas Ru SAs and clusters facilitated H2 desorption. Theoretical calculations revealed that Ru clusters + NPs cocatalyst were beneficial for H* intermediate formation. Water splitting tests found that 1.07 wt% Ru NPs + cluster modified CN showed the highest H2 evolution rate of 13.64 mmol h-1 g-1, which was 266.4 and 1.5 times higher than those of CN and Ru NPs (2.33 wt%) decorated CN, respectively. This work deeply reveals the influences of existential form of Ru cocatalysts on photocatalytic water splitting of CN, and provides thought in designing new cocatalysts to largely enhance H2 evolution.

Pd(II) coordination molecule modified g-C3N4 for boosting photocatalytic hydrogen production.

The photocatalytic H2 production activity of polymer carbon nitride (g-C3N4) is limited by the rapid recombination of photoelectron-hole pairs and slow surface reduction dynamic process. Here, a supramolecular complex (named R-TAP-Pd(II)) was fabricated via self-assembly of (R)-N-(1-phenylethyl)-4-(4-(pyridin-2-yl)-1H-1,2,3-triazol-1-yl)benzamide (R-TAP) with Pd(II) and used to modify g-C3N4. In the R-TAP-Pd(II)@g-C3N4 composite photocatalyst, the spin polarization of R-TAP-Pd(II) can promote charge transfer and inhibit photogenerated carrier recombination, as confirmed by spectral tests and photoelectrochemical performance tests. Electrochemical tests and in situ X-ray photoelectron spectroscopy (XPS) tests proved that the Pd(II) ion in the R-TAP-Pd(II) molecule can serve as active sites to accelerate H2 production. The R-TAP-Pd(II)@g-C3N4 presented a photocatalytic H2 generation rate of 1085 µmol g-1 h-1 when exposed to visible light, which was a about 278-fold increase compared with g-C3N4. This work finds a new approach to boost the photocatalytic efficiency of g-C3N4 via supramolecular self-assembly.

Rational Design of Improved Ru Containing Fe-Based Metal-Organic Framework (MOF) Photoanode for Artificial Photosynthesis.

Metal-Organic Frameworks (MOFs) recently emerged as a new platform for the realization of integrated devices for artificial photosynthesis. However, there remain few demonstrations of rational tuning of such devices for improved performance. Here, a fast molecular water oxidation catalyst working via water nucleophilic attack is integrated into the MOF MIL-142, wherein Fe3O nodes absorb visible light, leading to charge separation. Materials are characterized by a range of structural and spectroscopic techniques. New, [Ru(tpy)(Qc)(H2O)]+ (tpy = 2,2':6',2″-terpyridine and Qc = 8-quinolinecarboxylate)-doped Fe MIL-142 achieved a high photocurrent (1.6 × 10-3 A·cm-2) in photo-electrocatalytic water splitting at pH = 1. Unassisted photocatalytic H2 evolution is also reported with Pt as the co-catalyst (4.8 µmol g-1 min-1). The high activity of this new system enables hydrogen gas capture from an easy-to-manufacture, scaled-up prototype utilizing MOF deposited on FTO glass as a photoanode. These findings provide insights for the development of MOF-based light-driven water-splitting assemblies utilizing a minimal amount of precious metals and Fe-based photosensitizers.

Solvated Electrons Generated on the Surface of Na-SPHI for Boosting Visible Light Photocatalytic Hydrogen Evolution with Ultra-High AQE.

Enhancing the utilization of visible-light-active semiconductors with an excellent apparent quantum efficiency (AQE) remains a significant and challenging goal in the realm of photocatalytic water splitting. In this study, a fully condensed sulfur-doped poly(heptazine imide) metalized with Na (Na-SPHI) is synthesized by an ionothermal method by using eutectic NaCl/LiCl mixture as the ionic solvent. Comprehensive characterizations of the obtained Na-SPHI reveal several advantageous features, including heightened light absorption, facilitated exciton dissociation, and expedited charge transfer. More importantly, solvated electron, powerful reducing agents, can be generated on the surface of Na-SPHI upon irradiation with visible light. Benefiting from above advantage, the Na-SPHI exhibits an excellent H2 evolution rate of 571.8 µmol·h-1 under visible light illumination and a super-high AQE of 61.7% at 420 nm. This research emphasizes the significance of the solvated electron on the surface of photocatalyst in overcoming the challenges associated with visible light-driven photocatalysis, showcasing its potential application in photocatalytic water splitting.