Laser direct overall water splitting for H2 and H2O2 production.

Hydrogen (H2) and hydrogen peroxide (H2O2) play crucial roles as energy carriers and raw materials for industrial production. However, the current techniques for H2 and H2O2 production rely on complex catalysts and involve multiple intermediate steps. In this study, we present a straightforward, environmentally friendly, and highly efficient laser-induced conversion method for overall water splitting to simultaneously generate H2 and H2O2 at ambient conditions without any catalysts. The laser direct overall water splitting approach achieves an impressive light-to-hydrogen energy conversion efficiency of 2.1%, with H2 production rates of 2.2 mmol/h and H2O2 production rates of 65 µM/h in a limited reaction area (1 mm2) within a short real reaction time (0.36 ms/h). Furthermore, we elucidate the underlying physics and chemistry behind the laser-induced water splitting to produce H2 and H2O2. The laser-induced cavitation bubbles create an optimal microenvironment for water-splitting reactions because of the transient high temperatures (104 K) surpassing the chemical barrier required. Additionally, their rapid cooling rate (1010 K/s) hinders reverse reactions and facilitates H2O2 retention. Finally, upon bubble collapse, H2 is released while H2O2 remains dissolved in the water. Moreover, a preliminary amplification experiment demonstrates the potential industrial applications of this laser chemistry. These findings highlight that laser-based production of H2 and H2O2 from water holds promise as a straightforward, environmentally friendly, and efficient approach on an industrial scale beyond conventional chemical catalysis.

Nanofiber-Reinforced Composite Gel Enabling High Ionic Conductivity and Ultralong Cycle Life for Zn Ion Batteries.

Despite the impressive merits of gel electrolytes for aqueous Zn-ion batteries, it remains a significant challenge to design and develop the gel electrolyte with high ionic conductivity, excellent dimensional stability, and long cycle life. Herein, a composite electrolyte (PTP) with thermolastic polyurethane -poly(m-phenylene isophthalamide)  nanofiber-reinforced polyvinyl alcohol gel strategy is proposed for highly reversible Zn plating/stripping. Mechanically robust and ultrathin PTP contains functional groups for building ion migration channels and immobilizing water molecules, which accelerates Zn2+ migration and mitigates water-related side reactions. Thus, the Zn anodes exhibit excellent electrochemical performance involving high cycling stability (6500 h at 5 mA cm-2 , 5 mA h cm-2 ) and achieving an exceptional cumulative capacity of more than 16 000 mA h cm-2 . This enhancement is well maintained when combined with MnO2 cathode. This work provides a reasonable solution for stabilizing Zn anodes and also provides new ideas for the modification of nanofiber-reinforced gel electrolytes.

Simultaneous Efficient Photocatalytic Hydrogen Evolution and Degradation of Dye Wastewater without Cocatalysts and Sacrificial Agents Based on g-C3N5 and Hybridized Ni-MOF Derivative-CdS-DETA.

Inspired by energy conversion and waste reuse, hybridized Ni-MOF derivative-CdS-DETA/g-C3N5, a type-II heterojunction photocatalyst, is synthesized by a hydrothermal method for simultaneous and highly efficient photocatalytic degradation and hydrogen evolution in dye wastewater. Without the addition of cocatalysts and sacrificial agents, the optimal MOF-CD(2)/CN5 (i.e. Ni-MOF derivative-CdS-DETA (20 wt.%)/g-C3N5) exhibit good bifunctional catalytic activity, with a H2 evolution rate of 2974.4 µmol g-1 h-1 during the degradation of rhodamine B (RhB), and a removal rate of 99.97% for RhB. In the process of H2-evolution-only, triethanolamine is used as a sacrificial agent, exhibiting a high H2 evolution rate (19663.1 µmol g-1 h-1) in the absence of a cocatalyst, and outperforming most similar related materials (such as MOF/g-C3N5, MOF-CdS, CdS/g-C3N5). With the help of type-II heterojunction, holes are scavenged for the oxidative degradation of RhB, and electrons are used in the decomposition of water for H2 evolution during illumination. This work opens a new path for photocatalysts with dual functions of simultaneous efficient degradation and hydrogen evolution.

P-N Heterojunction Embedded CuS/TiO2 Bifunctional Photocatalyst for Synchronous Hydrogen Production and Benzylamine Conversion.

The coupling of photocatalytic hydrogen production and selective oxidation of benzylamine is a topic of significant research interest. However, enhancing the bifunctional photocatalytic activity in this context is still a major challenge. The construction of Z-scheme heterojunctions is an effective strategy to enhance the activity of bifunctional photocatalysts. Herein, a p-n type direct Z-scheme heterojunction CuS/TiO2 is constructed using metal-organic framework (MOF)-derived TiO2 as a substrate. The carrier density is measured by Mott-Schottky under photoexcitation, which confirms that the Z-scheme electron transfer mode of CuS/TiO2 is driven by the diffusion effect caused by the carrier concentration difference. Benefiting from efficient charge separation and transfer, photogenerated electrons, and holes are directedly transferred to active oxidation and reduction sites. CuS/TiO2 also exhibits excellent bifunctional photocatalytic activity without noble metal cocatalysts. Among them, the H2 evolution activity of the CuS/TiO2 is found to be 17.1 and 29.5 times higher than that of TiO2 and CuS, respectively. Additionally, the yields of N-Benzylidenebenzylamine (NBB) are 14.3 and 47.4 times higher than those of TiO2 and CuS, respectively.

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.

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.

Directional Charge Pumping from Photoactive P-doped CdS to Catalytic Active Ni2P via Funneled Bandgap and Bridged Interface for Greatly Enhanced Photocatalytic H2 Evolution.

Loading cocatalysts onto semiconductors is one of the most popular strategies to inhibit charge recombination, but the efficiency is generally hindered by the localized built-in electric field and the weakly connected interface. Here, this work designs and synthesizes a 1D P-doped CdS nanowire/Ni2P heterojunction with gradient doped P to address the challenges. In the composite, the gradient P doping not only creates a funneled bandgap structure with a built-in electric field oriented from the bulk of P-CdS to the surface, but also facilitates the formation of a tightly connected interface using the co-shared P element. Consequently, the photogenerated charge carriers are enabled to be pumped from inside to surface of the P-CdS and then smoothly across the interface to the Ni2P. The as-obtained P-CdS/Ni2P displays high visible-light-driven H2 evolution rate of ≈8265 µmol g-1 h-1, which is 336 times and 120 times as that of CdS and P-CdS, respectively. This work is anticipated to inspire more research attention for designing new gradient-doped semiconductor/cocatalyst heterojunction photocatalysts with bridged interface for efficient solar energy conversion.

Enhanced Spin-Polarized Electric Field Modulating p-Band Center on Ni-Doped CdS for Boosting Photocatalytic Hydrogen Evolution.

It is a challenge to regulate charge separation dynamics and redox reaction kinetics at the atomic level to synergistically boost photocatalytic hydrogen (H2) evolution. Herein, a robust Ni-doped CdS (Ni-CdS) photocatalyst is synthesized by incorporating highly dispersed Ni atoms into the CdS lattice in substitution for Cd atoms. Combined characterizations with theoretical analysis indicate that local lattice distortion and S-vacancy of Ni-CdS induced by Ni incorporation lead to an increased dipole moment and enhanced spin-polarized electric field, which promotes the separation and transfer of photoinduced carriers. In this contribution, charge redistribution caused by enhanced internal electric field results in the downshift of the S p-band center, which is conducive to the desorption of intermediate H* for boosting the H2 evolution reaction. Accordingly, the Ni-CdS photocatalyst shows a remarkably improved photocatalytic performance with an H2 evolution rate of 20.28 mmol g-1 h-1 under visible-light irradiation, which is 5.58 times higher than that of pristine CdS. This work supplied an insightful understanding that the enhanced polarization electric field governs the p-band center for efficient photocatalytic H2 evolution activity.

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.

Photothermal-Enhanced S-Scheme Heterojunction of Hollow Core-Shell FeNi2S4@ZnIn2S4 toward Photocatalytic Hydrogen Evolution.

Herein, guided by the results of density functional theory prediction, the study rationally designs a hollow core-shell FeNi2S4@ZnIn2S4 (FNS@ZIS) Step-scheme (S-scheme) heterojunction for photocatalytic H2 evolution with photothermal-assisted. The hollow FNS spheres offered substrate for coating the ZIS nanosheets, which can inhibit ZIS nanosheets from agglomerating into pellet, enrich the active site, increase specific surfaces, and raise the light absorption. Notably, due to its excellent photothermal properties, FNS core generated heat unceasingly inside under visible-light irradiation and effectively prevent the heat loss of the reaction system, which increased the local temperature of photocatalysts and thus accelerated the charge migration. In addition, the S-scheme heterojunction construction via in situ growth has a tight interface, which can facilitate the separation and transfer of carriers and achieve high redox potential. Owning to the distinctive construction, the hollow core-shell FNS@ZIS S-scheme heterojunction show extraordinary stability and photocatalytic H2 evolution rate with 7.7 mmol h-1 g-1, which is ≈15.2-fold than pristine ZIS. Based on the double evidence of theoretical predictions and experimental confirmations, the photothermal effect and electron transfer mechanism of this innovative material are investigated in depth by the following infrared thermography technology and deep DFT calculations.

2D Monolayer Catalysts: Towards Efficient Water Splitting and Green Hydrogen Production.

A viable alternative to non-renewable hydrocarbon fuels is hydrogen gas, created using a safe, environmentally friendly process like water splitting. An important role in water-splitting applications is played by the development of two-dimensional (2D) layered transition metal chalcogenides (TMDCs), transition metal carbides (MXenes), graphene-derived 2D layered nanomaterials, phosphorene, and hexagonal boron nitride. Advanced synthesis methods and characterization instruments enabled an effective application for improved electrocatalytic water splitting and sustainable hydrogen production. Enhancing active sites, modifying the phase and electronic structure, adding conductive elements like transition metals, forming heterostructures, altering the defect state, etc., can improve the catalytic activity of 2D stacked hybrid monolayer nanomaterials. The majority of global research and development is focused on finding safer substitutes for petrochemical fuels, and this review summarizes recent advancements in the field of 2D monolayer nanomaterials in water splitting for industrial-scale green hydrogen production and fuel cell applications.

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.

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.

Hydrogen Sulfide Splitting into Hydrogen and Sulfur through Off-Field Electrocatalysis.

Hydrogen sulfide (H2S), a toxic gas abundant in natural gas fields and refineries, is currently being removed mainly via the Claus process. However, the emission of sulfur-containing pollutants is hard to be prevented and the hydrogen element is combined to water. Herein, we report an electron-mediated off-field electrocatalysis approach (OFEC) for complete splitting of H2S into H2 and S under ambient conditions. Fe(III)/Fe(II) and V(II)/V(III) redox mediators are used to fulfill the cycles for H2S oxidation and H2 production, respectively. Fe(III) effectively removes H2S with almost 100% conversion during its oxidation process. The H+ ions are reduced by V(II) on a nonprecious metal catalyst, tungsten carbide. The mediators are regenerated in an electrolyzer at a cell voltage of 1.05 V, close to the theoretical potential difference (1.02 V) between Fe(III)/Fe(II) and V(II)/V(III). In a laboratory bench-scale plant, the energy consumption for the production of H2 from H2S is estimated to be 2.8 kWh Nm-3 H2 using Fe(III)/Fe(II) and V(II)/V(III) mediators and further reduced to about 0.5 kWh Nm-3 H2 when employing well-designed heteropolyacid/quinone mediators. OFEC presents a cost-effective approach for the simultaneous production of H2 and elemental sulfur from H2S, along with the complete removal of H2S from industrial processes. It also provides a practical platform for electrochemical reactions involving solid precipitation and organic synthesis.

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.

Rational Photodeposition of Cobalt Phosphate on Flower-like ZnIn2S4 for Efficient Photocatalytic Hydrogen Evolution.

The high electrons and holes recombination rate of ZnIn2S4 significantly limits its photocatalytic performance. Herein, a simple in situ photodeposition strategy is adopted to introduce the cocatalyst cobalt phosphate (Co-Pi) on ZnIn2S4, aiming at facilitating the separation of electron-hole by promoting the transfer of photogenerated holes of ZnIn2S4. The study reveals that the composite catalyst has superior photocatalytic performance than blank ZnIn2S4. In particular, ZnIn2S4 loaded with 5% Co-Pi (ZnIn2S4/5%Co-Pi) has the best photocatalytic activity, and the H2 production rate reaches 3593 µmol·g-1·h-1, approximately double that of ZnIn2S4 alone. Subsequent characterization data demonstrate that the introduction of the cocatalyst Co-Pi facilitates the transfer of ZnIn2S4 holes, thus improving the efficiency of photogenerated carrier separation. This investigation focuses on the rational utilization of high-content and rich cocatalysts on earth to design low-cost and efficient composite catalysts to achieve sustainable photocatalytic hydrogen evolution.

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.

Confinement of CsPbBr3 Perovskite Nanocrystals into Extra-large-pore Zeolite for Efficient and Stable Photocatalytic Hydrogen Evolution.

Metal halide perovskites (MHPs), renowned for their outstanding optoelectronic properties, hold significant promise as photocatalysts for hydrogen evolution reaction (HER). However, the low stability and insufficient exposure of catalytically active sites of bulky MHPs seriously impair their catalytic efficiency. Herein, we utilized an extra-large-pore zeolite ZEO-1 (JZO) as a host to confine and stabilize the CsPbBr3 nanocrystals (3.4 nm) for boosting hydrogen iodide (HI) splitting. The as-prepared CsPbBr3@ZEO-1 featured sufficiently exposed active sites, superior stability in acidic media, along with intrinsic extra-large pores of ZEO-1 that were favorable for molecule/ion adsorption and diffusion. Most importantly, the unique nanoconfinement effect of ZEO-1 led to the narrowing of the band gap of CsPbBr3, allowing for more efficient light utilization. As a result, the photocatalytic HER rate of the as-prepared CsPbBr3@ZEO-1 photocatalyst was increased to 1734 µmol ⋅ h-1 ⋅ g-1 (CsPbBr3) under visible light irradiation compared with bulk CsPbBr3 (11 µmol ⋅ h-1 ⋅ g-1 (CsPbBr3)), and the long-term durability (36 h) can be achieved. Furthermore, Pt was incorporated with well-dispersed CsPbBr3 nanocrystals into ZEO-1, resulting in a significant enhancement in activity (4826 µmol ⋅ h-1 ⋅ g-1 (CsPbBr3)), surpassing most of the Pt-integrated perovskite-based photocatalysts. Density functional theory (DFT) calculations and charge-carrier dynamics investigation revealed that the dramatically boosted photocatalytic performance of Pt/CsPbBr3@ZEO-1 could be attributed to the promotion of charge separation and transfer, as well as to the substantially lowered energy barrier for HER. This work highlights the advantage of extra-large-pore zeolites as the nanoscale platform to accommodate multiple photoactive components, opening up promising prospects in the design and exploitation of novel zeolite-confined photocatalysts for energy harvesting and storage.

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.

Spontaneous Dewetting of Au-Thin Layers on Oxide- and Fluorine-Terminated Single Crystalline Anatase and Efficient Use in Photocatalytic H2 Production.

In the present work, the spontaneous dewetting of thin Au layers on single crystalline anatase nanosheets into narrow-disperse Au nanoparticles is investigated. Patterns of the Au particles can be formed on the main facets of anatase that provide a high co-catalytic activity for photocatalytic generation of H2 . Dewetting is distinctly influenced by the respective facets (001) and (101), the deposit thickness, and secondary thermal dewetting, but most strongly by the surface termination of the nanosheets. Fluoride termination not only leads to an enhanced Au-phobic behavior but strongly affects the co-catalytic activity for photocatalytic generation of H2 . While fluoride termination with or without Au decoration is detrimental for hole transfer, the interplay of the Au co-catalyst and surface fluoride yields highly beneficial effect for electron transfer. This results in a three-times higher photocatalytic H2 production for the F-terminated surface. The findings suggest that dewetting of Au on surface fluorinated TiO2 is an effective way to modulate surface dewetting and achieve a strongly enhanced photocatalytic activity.