Highly ordered aggregation of soy protein isolate particles for enhanced gel-related properties through konjac glucomannan addition.

This study assessed the effect of konjac glucomannan (KGM) on the aggregation of soy protein isolate (SPI) and its gel-related structure and properties. Raman results showed that KGM promoted the rearrangement of SPI to form more ß-sheets, contributing to the formation of an ordered structure. Atomic force microscopy, confocal laser scanning microscopy, and small-angle X-ray scattering results indicated that KGM reduced the size of SPI particles, narrowed their size distribution, and loosened the large aggregates formed by the stacking of SPI particles, improving the uniformity of gel system. As the hydrogen bonding between the KGM and SPI molecules enhanced, a well-developed network structure was obtained, further reducing the immobilized water's content (T22) and increasing the water-holding capacity (WHC) of SPI gel. Furthermore, this gel structure showed improved gel hardness and resistance to both small and large deformations. These findings facilitate the design and production of SPI-based gels with desired performance.

Binding and distribution regularity of water molecules in high-moisture textured Antarctic krill (Euphausia superba) meat.

High-moisture extrusion technique with the advantage of high efficiency and low energy consumption is a promising strategy for processing Antarctic krill meat. Consequently, this study aimed to prepare high-moisture textured Antarctic krill meat (HMTAKM) with a rich fiber structure at different water contents (53 %, 57 %, and 61 %) and to reveal the binding and distribution regularity of water molecules, which is closely related to the fiber structure of HMTAKM and has been less studied. The hydrogen-bond network results indicated the presence of at least two or more types of water molecules with different hydrogen bonds. Increasing the water content of HMTAKM promoted the formation of hydrogen bonds between the water molecules and protein molecules, leading to the transition of the ß-sheet to the α-helix. These findings offer a novel viable processing technique for Antarctic krill and a new understanding of the fiber formation of high-moisture textured proteins.

Study of chemical reactivity and molecular interactions of the hydrochlorothiazide-4-aminobenzoic acid cocrystal using spectroscopic and quantum chemical approaches.

In this study, the molecular, electronic, and chemical properties of the drug hydrochlorothiazide (HCTZ) are determined after cocrystallization with 4-aminobenzoic acid (4-ABA). Analysis has been performed to understand how those variations lead to alteration of physical properties and chemical reactivity in the cocrystal HCTZ-4ABA. IR and Raman characterizations were performed along with quantum chemical calculations. A theoretical investigation of hydrogen bonding interactions in HCTZ-4ABA has been conducted using two functionals: B3LYP and wB97X-D. The results obtained by B3LYP and wB97X-D are compared which leads to the conclusion that B3LYP is the best applied function (density functional theory) to obtain suitable results for spectroscopy. The chemical reactivity descriptors are used to understand various aspects of pharmaceutical properties. Natural bond orbital (NBO) analysis and quantum theory of atoms (QTAIM) are used to analyze nature and strength of hydrogen bonding in HCTZ-4ABA. QTAIM analyzed moderate role of hydrogen bonding interactions in HCTZ-4ABA. The calculated HOMO-LUMO energy gap shows that HCTZ-4ABA is chemically more active than HCTZ drug. These chemical parameters suggest that HCTZ-4ABA is chemically more reactive and softer than HCTZ. The results of this study suggest that cocrystals can be a good alternative for enhancing physicochemical properties of a drug without altering its therapeutic properties.

Mitochondrial 'Birth-Death' coordinator: An intelligent hydrogen nanogenerator to enhance intervertebral disc regeneration.

Currently, mitochondrial dysfunction caused by oxidative stress is a growing concern in degenerative diseases, notably intervertebral disc degeneration (IVDD). Dysregulation of the balance of mitochondrial quality control (MQC) has been considered the key contributor, while it's still challenging to effectively harmonize different MQC components in a simple and biologically safe way. Hydrogen gas (H2) is a promising mitochondrial therapeutic molecule due to its bio-reductivity and diffusibility across cellular membranes, yet its relationship with MQC regulation remains unknown. Herein, we propose a mitochondrial 'Birth-Death' coordinator achieved by an intelligent hydrogen nanogenerator (Fe@HP-OD), which can sustainably release H2 in response to the unique microenvironment in degenerated IVDs. Both in vitro and in vivo results prove alleviation of cellular oxidative stress and restoration of nucleus pulposus cells function, thereby facilitating successful IVD regeneration. Significantly, this study for the first time proposes the mitochondrial 'Birth-Death' coordination mechanism: 1) attenuation of overactivated mitochondrial 'Death' process (UPRmt and unselective mitophagy); and 2) activation of Adenosine 5'-monophosphate-activated protein kinase (AMPK) signaling pathway for mitochondrial 'Birth-Death' balance (mitochondrial biogenesis and controlled mitophagy). These pioneering findings can fill in the gaps in molecular mechanisms for H2 regulation on MQC homeostasis, and pave the way for future strategies towards restoring equilibrium of MQC system against degenerative diseases.

Anchoring Pt single atoms on specific nitrogen vacancies of carbon nitride to accelerate photogenerated carrier transfer.

The anchoring sites of metal single atoms are closely related to photogenerated carrier dynamics and surface reactions. Achieving smooth photogenerated charge transfer through precise design of single-atom anchoring sites is an effective strategy to enhance the activity of photocatalytic hydrogen evolution. In this study, Pt single atoms were loaded onto ultra-thin carbon nitride with two-coordination nitrogen vacancies (VN2c-UCN-Pt) and ultra-thin carbon nitride with three-coordination nitrogen vacancies (VN3c-UCN-Pt). This paper investigated the photocatalytic hydrogen evolution performance and photogenerated carrier behavior of Pt single atoms at different anchoring sites. Surface photovoltage measurements indicated that VN2c-UCN-Pt exhibits a superior carrier separation efficiency compared to VN3c-UCN-Pt. More importantly, the surface photovoltage signal under the presence of H2O molecules revealed a significant decrease. Theoretical calculations suggest that VN2c-UCN-Pt exhibits superior capabilities in adsorbing and activating H2O molecules. Consequently, the photocatalytic hydrogen evolution efficiency of VN2c-UCN-Pt reaches 1774 µmol g-1h-1, which is 1.8 times that of VN3c-UCN-Pt with the same Pt loading. This work emphasized the structure-activity relationship between single-atom anchoring sites and photocatalytic activity, providing a new perspective for designing precisely dispersed single-atom sites to achieve efficient photocatalytic hydrogen evolution.

Construction of porous Cu/CeO2 catalyst with abundant interfacial sites for effective methanol steam reforming.

Methanol is a promising hydrogen carrier for fuel cell vehicles (FCVs) via methanol steam reforming (MSR) reaction. Ceria supported copper catalyst has attracted extensive attentions due to the extraordinary oxygen storage capacity and abundant oxygen vacancies. Herein, we developed a colloidal solution combustion (CSC) method to synthesize a porous Cu/CeO2(CSC) catalyst. Compared with Cu/CeO2 catalysts prepared by other methods, the Cu/CeO2(CSC) catalyst possesses highly dispersed copper species and abundant Cu+-Ov-Ce3+ sites at the copper-ceria interface, contributing to methanol conversion of 66.3 %, CO2 selectivity of 99.2 %, and outstanding hydrogen production rate of 490 mmol gcat-1 h-1 under 250 °C. The linear correlation between TOF values and Cu+-Ov-Ce3+ sites amount indicates the vital role of Cu+-Ov-Ce3+ sites in MSR reaction, presenting efficient ability in activation of water. Subsequently, a deep understanding of CSC method is further presented. In addition to serving as a hard template, the colloidal silica also acts as disperser between nanoparticles, enhancing the copper-ceria interactions and facilitating the generation of Cu+-Ov-Ce3+ sites. This study offers an alternative approach to synthesize highly dispersed supported copper catalysts.

Regulating the electronic structure of Pt SAs-Ni2P for enhanced hydrogen evolution reaction.

The single atom catalysts (SACs) show immense promise as catalytic materials. By doping the single atoms (SAs) of precious metals onto substrates, the atomic utilization of these metals can be maximized, thereby reducing catalyst costs. The electronic structure of precious metal SAs is significantly influenced by compositions of doped substrates. Therefore, optimizing the electronic structure through appropriate doping of substrates can further enhance catalytic activity. Here, Pt single atoms (Pt SAs) are doped onto transition metal sulfide substrate NiS2 (Pt SAs-NiS2) and phosphide substrate Ni2P (Pt SAs-Ni2P) to design and prepare catalysts. Compared to the Pt SAs-NiS2 catalyst, the Pt SAs-Ni2P catalyst exhibits better hydrogen evolution catalytic performance and stability. Under 1 M KOH conditions, the hydrogen evolution mass activity current density of the Pt SAs-Ni2P catalyst reaches 0.225 A mgPt-1 at 50 mV, which is 33 times higher than that of commercial Pt/C catalysts. It requires only 44.9 mV to achieve a current density of 10 mA cm-2. In contrast, for the Pt SAs-NiS2 catalyst, the hydrogen evolution mass activity current density is 0.178 A mgPt-1, requiring 77.8 mV to achieve a current density of 10 mA cm-2. Theoretical calculations indicate that in Pt SAs-Ni2P, the interaction between Pt SAs and the Ni2P substrate causes the Pt d-band center to shift downward, enhancing the H2O desorption and providing optimal H binding sites. Additionally, the hollow octahedral morphology of Ni2P provides a larger surface area, exposing more reactive sites and improving reaction kinetics. This study presents an effective pathway for preparing high-performance hydrogen evolution electrocatalysts by selecting appropriate doped substrates to control the electronic structure of Pt SAs.

Cation/anion-doping induced electronic structure modulation of CoMoO4 for enhanced hydrogen evolution.

The design and fabrication of high-performance, inexpensive and durable electrocatalyst toward hydrogen evolution reaction (HER) is supremely significant for alleviating energy crisis and environmental concerns, but still remaining challenging. Herein, we develop an experimental work based on etching and reduction strategy to reveal the remarkable effect of cation/anion co-doping in CoMoO4 on its intrinsic HER activity. The CoMoO4 with Fe and B incorporation (Fe/B-CoMoO4) exhibits a current density of 10 mA cm-2 with strikingly low potential of 38 mV coupling with Tafel slope of 51 mV dec-1, and manifesting a robust durability for 100 h with no attenuation, which is comparable to the state-of-the-art commercial Pt/C catalyst. The collective experimental and theoretical findings concomitantly illustrate that the enhanced performances are due to the strong synergistic effect resulting from the co-doping of Fe and B, which plays a pivotal role in finely tuning the electronic structure of CoMoO4, further optimizing the adsorption free energy of H intermediates and shifting the center of the d-band of Fe/B-CoMoO4 away from the Fermi level. This fantastic work highlights the critical role of foreign element incorporating for optimizing electronic structure of transition metal oxides toward HER, and offers valuable guiding principles for rational design of more efficient energy conversion devices.

Transition metals-based electrocatalysts on super-flat substrate for perovskite photovoltaic hydrogen production with 13.75% solar to hydrogen efficiency.

Harnessing the inexhaustible solar energy for water splitting is regarded one of the most promising strategies for hydrogen production. However, sluggish kinetics of oxygen evolution reaction (OER) and expensive photovoltaics have hindered commercial viability. Here, an adhesive-free electrodeposition process is developed for in-situ preparation of earth-abundant electrocatalysts on super-flat indium tin oxide (ITO) substrate. NiFe hydroxide exhibited prominent OER performance, achieving an ultra-low overpotential of 236 mV at 10 mA/cm2 in alkaline solution. With the superior OER activity, we achieved an unassisted solar water splitting by series connected perovskite solar cells (PSCs) of 2 cm2 aperture area with NiFe/ITO//Pt electrodes, yielding overall solar to hydrogen (STH) efficiency of 13.75 %. Furthermore, we upscaled the monolithic facility to utilize perovskite solar module for large-scale hydrogen production and maintained an approximate operating current of 20 mA. This creative strategy contributes to the decrease of industrial manufacturing expenses for perovskite-based photovoltaic-electrochemical (PV-EC) hydrogen production, further accelerating the conversion and utilization of carbon-free energy.

Sulfur occupancy-induced construction of ant-nest-like NiMo/CF(N) electrode for highly efficient hydrogen evolution.

The microstructure of the electrocatalyst plays a critical role in the reaction efficiency and stability during electrochemical water splitting. Designing an efficient and stable electrocatalyst, further clarifying the synthesis mechanism, is still an important problem to be solved urgently. Inspired by the copper pyrometallurgy theory, an exceptionally active NiMo/CF(N) electrode, consisting of an ant-nest-like copper foam substrate (defined as CF(N)) and deposited NiMo layer, was fabricated for the alkaline hydrogen evolution reaction (HER). Our findings expounded the structure construction mechanism and highlighted the pivotal role of the spatial occupancy of sulfur atoms in the construction of the ant-nest-like structure. The NiMo/CF(N) composite, characterized by channels with a 2 µm diameter, showcases strong electronic interactions, increased catalytic active sites, enhanced electron/ion transport, and facilitated gas release during HER. Remarkably, NiMo/CF(N) demonstrates ultralow overpotentials of 21 mV to deliver a current density of 10 mA cm-2 in 1 M KOH. This electrode also exhibits outstanding durability, maintaining a current density of 200 mA cm-2 for 110 h, attributed to the chemical and structural integrity of its catalytic surface and the excellent mechanical properties of the electrode. This work advances the fundamental understanding of constructing micro/nano-structured electrocatalysts for highly efficient water splitting.

Synergistic regulation of d-band center photocatalytic hydrogen evolution at S-scheme heterojunction reduction sites through defect engineering and interface electric field.

The efficiency of photocatalytic hydrogen evolution can be significantly enhanced while maintaining cost-effectiveness through the synergistic effect of defect surface engineering and multi-component heterojunctions. The structure and properties of NiCo2O4 nanorods were modified by inducing oxygen vacancies at different temperatures in this study, resulting in improved optical properties and electron adsorption capacity. The presence of oxygen vacancies leads to a reduction in the band gap of NiCo2O4, thereby enhancing electron transport efficiency through band gap engineering. Simultaneously, surface properties undergo changes, and vacancy defects serve as electron trapping centers, facilitating an increased participation of electrons in the hydrogen evolution reaction process. The dodecahedron KMP with a cavity structure is additionally introduced to form an S-scheme heterojunction with NiCo2O4. This establishes a novel mechanism for electron transport, which effectively enhances the separation of electron-hole pairs and improves the redox capacity of the photocatalytic system. The adsorption of intermediates in the hydrogen production process is enhanced through synergistic regulation of d-band centers via surface defect engineering and S-scheme heterojunction. Additionally, this approach improves the separation efficiency of electron-hole pairs and accelerates electron transfer dynamics, significantly enhancing hydrogen production efficiency.

Boosting supercapacitive performance of pristine covalent organic frameworks via phenolic hydroxyl groups: A two-in-one strategy.

Two-dimensional covalent organic frameworks (COFs) are ideal electrode materials for electrochemical energy storage devices due to their unique structures and properties, and the accessibility and utilization efficiency of the redox-active sites within COFs are critical determinants of their pseudocapacitive performance. Via introducing meticulously designed phenolic hydroxyl (Ar-OH) groups with hydrogen-bond forming ability onto the imine COF skeletons, DHBD-Sb-COF exhibited improved hydrophilicity and crystallinity than the parent BD-Sb-COF, the redox-active sites (SbPh3 moieties) in COF electrodes could thus be highly accessed by aqueous electrolyte with a high active-site utilization of 93%. DHBD-Sb-COF//AC provided an excellent supercapacitive performance with an energy density of 78 Wh Kg-1 at the power density of 2553 W Kg-1 and super cycling stability, exceeding most of the previously reported pristine COF electrode-based supercapacitors. The "two-in-one" strategy of introducing hydroxyl groups onto imine COF skeletons to enhance both hydrophilicity and crystallinity provides a new avenue to improve the electrochemical performance of COF-based electrodes for high-performance supercapacitors.

Synergistic engineering of heterostructure and oxygen vacancy in cobalt hydroxide/aluminum oxyhydroxide as bifunctional electrocatalysts for urea-assisted hydrogen production.

Designing inexpensive, high-efficiency and durable bifunctional catalysts for urea oxidation reaction (UOR) and hydrogen evolution reaction (HER) is an encouraging tactic to produce hydrogen with reduced energy expenditure. Herein, oxygen vacancy-rich cobalt hydroxide/aluminum oxyhydroxide heterostructure on nickel foam (denoted as Co(OH)2/AlOOH/NF-100) has been fabricated using one step hydrothermal process. Theoretical calculation and experimental results indicate the electrons transfer from Co(OH)2 to highly active AlOOH results in the interfacial charge redistribution and optimization of electronic structure. Abundant oxygen vacancies in the heterostructure could improve the conductivity and simultaneously serve as the active sites for catalytic reaction. Consequently, the optimal Co(OH)2/AlOOH/NF-100 demonstrates excellent electrocatalytic performance for HER (62.9 mV@10 mA cm-2) and UOR (1.36 V@10 mA cm-2) due to the synergy between heterointerface and oxygen vacancies. Additionally, the in situ electrochemical impedance spectrum (EIS) for UOR suggests that the heterostructured catalyst exhibits rapid reaction kinetics, mass transfer and current response. Importantly, the urea-assisted electrolysis composed of the Co(OH)2/AlOOH/NF-100 manifests a low cell voltage (1.48 V @ 10 mA cm-2) in 1 M KOH containing 0.5 M urea. This work presents a promising avenue to the development of HER/UOR bifunctional electrocatalysts.

Facile synthesis of hierarchical core-shell carbon@ZnIn2S4 composite for boosted photothermal-assisted photocatalytic H2 production.

Against the backdrop of energy shortage, hydrogen energy has attracted much attention as a green and clean energy source. In order to explore efficient hydrogen production pathways, we designed a composite photocatalyst with carbon-based core-shell photothermal-assisted photocatalytic system (Carbon@ZnIn2S4, denoted as C@ZIS). The well-designed catalyst C@ZIS composites demonstrated a photocatalytic hydrogen precipitation rate of 2.97 mmol g-1 h-1 even in the absence of the noble metal Pt co-catalyst. The incorporation of carbon-based core-shell photocatalysts into a photocatalytic reaction significantly affects the activity of the reaction by triggering a photothermal effect in the reaction solution. The results of the physicochemical experiments demonstrated that the carbon spheres in C@ZIS composite system could provide a greater number of active sites, thereby accelerating the electron transfer and separation efficiency, and thus enhancing the photocatalytic activity. The study presents an efficacious design concept for the development of efficacious carbon-based core-shell photothermal-assisted photocatalysts, which is anticipated to facilitate the efficient conversion of solar energy to hydrogen energy.

Optimizing photocatalytic hydrogen evolution performance by rationally constructing S-scheme heterojunction to modulate the D-band center.

The research in the field of photocatalysis has progressed, with the development of heterojunctions being recognized as an effective method to improve carrier separation efficiency in light-induced processes. In this particular study, CuCo2S4 particles were attached to a new cubic CdS surface to create an S-scheme heterojunction, thus successfully addressing this issue. Specifically, owing to the higher conduction band and Fermi level of CuCo2S4 compared to CdS, they serve as the foundation and driving force for the formation of an S-scheme heterojunction. Through in-situ X-ray photoelectron spectroscopy and electron paramagnetic resonance analysis, the direction of charge transfer in the composite photocatalyst under light exposure was determined, confirming the charge transfer mechanism of the S-scheme heterojunction. By effectively constructing the S-scheme heterojunction, the d-band center of the composite photocatalyst was adjusted, reducing the energy needed for electron filling in the anti-bonding energy band, promoting the transfer of photogenerated carriers, and ultimately enhancing the photocatalytic hydrogen production. performance. After optimization, the hydrogen evolution activity of the composite photocatalyst CdS-C/CuCo2S4-3 reached 5818.9 µmol g-1h-1, which is 2.6 times higher than that of cubic CdS (2272.3 µmol g-1h-1) and 327.4 times higher than that of CuCo2S4 (17.8 µmol g-1h-1), showcasing exceptional photocatalytic activity. Electron paramagnetic resonance and in situ X-ray photoelectron spectroscopy have established a theoretical basis for designing and constructing S-scheme heterojunctions, offering a viable method for adjusting the D-band center to enhance the performance of photocatalytic hydrogen evolution.

Low Rh doping accelerated HER/OER bifunctional catalytic activities of nanoflower-like Ni-Co sulfide for greatly boosting overall water splitting.

Facile synthesis of high-efficiency and stable bifunctional electrocatalyst is essential for producing clean hydrogen in energy storage systems. Herein, low Rh-doped flower-like Ni3S2/Co3S4 heterostructures were facilely prepared on porous nickel foam (labeled Rh-Ni3S2/Co3S4/NF) by a hydrothermal method. The correlation of the precursors types with the morphological structures and catalytic properties were rigorously investigated for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in the control groups. The low Rh doping within the catalyst played important role in boosting the catalytic characteristics. The resulting catalyst showed the smaller overpotentials of 197 and 78 mV to drive a current density of 10 mA cm-2 for the OER and HER in alkaline electrolyte, respectively. And the potential only required 1.71 V to drive a current density of 100 mA cm-2 in a water splitting device. It reflects excellent overall water splitting of the home-made Rh-Ni3S2/Co3S4/NF. This strategy shed some constructive light for preparing transition metal sulfide-based electrocatalysts in water splitting devices.

Boosting electrocatalytic hydrogen evolution via partial oxidation of rhenium through cobalt modification in nanoalloy structure.

Although the theoretical electrocatalytic activity of rhenium (Re) for the hydrogen evolution reaction is comparable to that of platinum, the experimental performance of reported rhenium-based electrocatalysts remains unsatisfactory. Herein, we report a highly efficient and stable electrocatalyst composed of rhenium and cobalt (Co) nanoalloy embedded in nitrogen-doped carbon film (Re3Co2@NCF). The Re3Co2@NCF electrocatalyst exhibited remarkable hydrogen evolution performance, with an overpotential as low as 30 ± 3 mV to reach a current density of 10 mA cm-2. In addition, the Re3Co2@NCF demonstrated exceptional stability over several days at a current density of 150 mA cm-2. Theoretical calculations revealed that alloying cobalt with rhenium altered the electronic structure of the metals, causing partial oxidation of the superficial metal atoms. This modification provided a balance for various intermediates' adsorption and desorption, thereby boosting the intrinsic activity of rhenium for hydrogen evolution reaction. This work improves the electrocatalytic performance of rhenium to its theoretical activity, suggesting a promising future for rhenium-based electrocatalysts.

Metal organic framework-assisted copper-modified titania (Cu/TiO2) with abundant exposed active sites and highly accessible pore channels for an enhanced photo-generation of hydrogen.

Metal-doping is a common strategy for establishing active sites on photocatalyst, but appropriately exposing them for maximized atomic utilization remains a great challenge in photocatalytic research. Herein, we propose a metal organic framework (MOF)-assisted approach to synthesis copper-modified titania (Cu-TiO2/Cu) photocatalyst with homogenously distributed and highly accessible active sites in its matrix. Significantly, an MOF precursor, namely NH2-MIL-125, with co-chelation of titania (Ti) and copper (Cu) was subjected to mild calcination, subsequently results in Cu-modified TiO2 with highly accessible channels to its inner surface. These channels provide not only a large reactive surface (>400 m2 g-1); they also enable facile modifying route for the pre-deposited Cu in prior to photoreaction. Specifically, NH3 treatment was applied to partially reduce deposited Cu ions (Cu+ and Cu2+) into Cu nanoparticles, where their interplays realize improved optical properties and charge separation during photoreactions. Furthermore, the NH3-induced Cu nanoparticles could also serve as the adsorptive site for H+, thereby enabling 5629 µmol h-1 g-1 H2 generation over the optimum photocatalyst of Cu20/TiO2/Cu500. Such performance is associated to 35.44 and 1.71-fold improvements compared to pure TiO2 (Cu0/TiO2) and untreated Cu-ion modified TiO2 (Cu20/TiO2), respectively. This work offers a new synthetic strategy for obtaining photocatalyst with evenly distributed and highly accessible active sites, thus improving the commensurability of photocatalytic H2 generation from the industrial perspective.

Construction of 2D/2D S-scheme Bi2MoO6/Zn-TCPP heterojunction via in-situ self-assembly growth strategy to enhance interface effect for efficient photocatalytic hydrogen production.

Two-dimensional/two-dimensional (2D/2D) heterojunctions are considered to be an effective strategy for forming strong interface effects and facilitating photogenerated carrier separation. However, it is usually limited by the size mismatch of the materials, even at the expense of its redox capability. Herein, 2D/2D S-scheme heterojunction photocatalyst Bi2MoO6/Zn-TCPP (BMO/ZTP) composed of 2D Bi2MoO6 and 2D Zn-TCPP (TCPP: tetrakis (4-carboxyphenyl) porphyrin) (MOFs) was constructed by in-situ self-assembly growth strategy. The size-compatible 2D/2D composites had abundant surface active sites and strong interactions. In addition, band bending and interfacial electric field (IEF) effect based on S-scheme heterojunction could accelerate the separation and migration of photogenerated carriers in BMO/ZTP. The best hydrogen precipitation rate of the BMO/ZTP was 10900.94 umol·g-1·h-1, which was 38.90 and 3.24 times higher than that of Bi2MoO6 (280.26 umol·g-1·h-1) and Zn-TCPP (3360.34 umol·g-1·h-1), respectively. The results indicated that 2D/2D BMO/ZTP S-scheme heterojunction could enhance the interface effect and retain strong reducing electrons to achieve efficient photocatalytic hydrogen production, which was confirmed by ultraviolet photoelectron spectroscopy (UPS), Tafel curve, electron spin resonance (ESR) and time-resolved photoluminescence (TRPL) characterization and density functional theory (DFT) calculations. This work provided a general strategy for constructing 2D Bi2MoO6 and 2D MOFs S-scheme heterojunctions to enhance interface effects for achieving efficient photocatalytic hydrogen production.

Integrated doped-Ru electrocatalyst with excellent H adsorption-desorption and active site on hollow tubular structures for boosting efficient hydrogen evolution.

Electrochemical water splitting for hydrogen production is an ideal process for clean energy production. However, highly active and low-cost electrocatalysts are essential and challenging. In this work, a multi-component Cu-based catalyst (Ru-M-C-Cu), synergized with ruthenium (Ru) heteroatom doping, was synthesized via a facile immersion-calcination-immersion method. Based on the cotton biomass substrate, a hollow tubular structure was obtained. By virtue of its distinctive structure and high carbon content, cotton biomass assumed a dual role as a sacrificial template and a reducing agent in the eco-friendly synthesis of electrocatalysts, which was instrumental in the creation of a multi-component system augmented by heteroatom doping. The multi-component system was constructed by in-situ transformation and redox reaction during calcination in an oxygen-free environment. The Ru-M-C-Cu catalyst exhibited a competitive overpotential of 108 mV at a current density of 10 mA cm-2 for alkaline hydrogen evolution reaction (HER). The satisfactory catalytic performance of Ru-M-C-Cu can be attributed to the fact that the Ru-O-Cu catalytic centers enhanced the adsorption and desorption abilities of the Cu-O active sites toward hydrogen. Furthermore, the hollow tubular structure allowed the electrolyte to make full contact with the active sites of the Ru-M-C-Cu catalyst, thus accelerated the HER kinetics. The catalyst showed structural and chemical stability after a 12-hour successive test. Besides, the production cost of Ru-M-C-Cu was significantly reduced by 99.1 % than that of commercial 20 % Pt/C, showing the potential as an alternative catalyst by offering a more accessible and sustainable source. This work provides a new design of sustainable low-budget electrocatalysts with the proposed strategies expected for producing clean and renewable hydrogen energy.