Fine-Tuning Graph Neural Networks via Active Learning: Unlocking the Potential of Graph Neural Networks Trained on Nonaqueous Systems for Aqueous CO Reduction.

Graph neural networks (GNNs) have revolutionized catalysis research with their efficiency and accuracy in modeling complex chemical interactions. However, adapting GNNs trained on nonaqueous data sets to aqueous systems poses notable challenges due to intricate water interactions. In this study, we proposed an active learning-based fine-tuning approach to extend the applicability of GNNs to aqueous environments.

A photothermal-photocatalytic layered aerogel for harvesting water and hydrogen from seawater.

Photocatalytic hydrogen production from seawater holds potential to decrease the use of fresh or pre-treated water. However, direct photocatalytic splitting of seawater currently encounters challenges such as corrosion of catalyst and unsatisfied stability. To address these issues, we have integrated seawater desalination with photocatalytic water vapor splitting for in-situ hydrogen production, while also obtaining freshwater.

Size Effects on Bubble Dynamics during Photoelectrochemical Water Splitting.

The rapid bubble removal from electrodes diminishes the reaction resistance within photoelectrochemical water splitting, and the coalescence between bubbles accelerates their detachment. To delve into the size effects on bubble coalescence dynamics, the Marangoni effect is utilized as a noninvasively controlling means of bubble sliding and coalescence. The study reveals that the encounter of capillary waves induces bubble detachment.

Mechanistic insight into the decomposition of sulfone compounds in supercritical water.

Supercritical water gasification (SCWG) is famous for the clean utilization of organic wastes without SO emission. Investigating the decomposition mechanism of sulfone compounds, the dominant organic sulfur compounds of organic wastes, in supercritical water (SCW) is conducive to the development of SCWG technology. Herein, the comparative decomposition mechanism of phenyl vinyl sulfone (PVS), diphenyl sulfone (DS), and benzo[b]thiophene 1,1-dioxide (BD) are explored via experiments and density functional theoretical (DFT) calculations.

Awakening n-π* electron transition in structurally distorted g-CN nanosheets via hexamethylenetetramine-involved supercritical CO treatment towards efficient photocatalytic H production.

Graphitic carbon nitride (g-CN) has been regarded as highly potential photocatalyst for solar energy utilization. However, the restricted absorption of visible light for pristine g-CN significantly limits the solar-light-driven chemical reaction efficiency. Herein, structurally distorted g-CN nanosheets with awakened n-π* electron transition were successfully synthesized through hexamethylenetetramine (HMTA)-involved supercritical CO (scCO) treatment and following pyrolysis of melamine precursor.

Cu-ZnS Modulated Multi-Carbon Coupling Enables High Selectivity Photoreduction CO to CHCHCOOH.

The direct photocatalytic conversion of CO and HO into high-value C chemicals holds great promise but remains challenging due to the intrinsic difficulty of C-C and C-C coupling processes and the lack of clarity regarding the underlying reaction mechanisms. Here, the design and synthesis of a Cu-ZnS photocatalyst featuring dispersed Cu single atoms are reported. These Cu single atoms are coordinated with S atoms, forming unique Cu-S-Zn active units with tunable charge distributions that interact favorably with surface-adsorbed intermediates.

Anti-Site Defect-Induced Cascaded Sub-Band Transition in CuInS Enables Infrared Light-Driven CO Reduction.

Photocatalytic CO conversion is a promising approach to simultaneously mitigate climate change and alleviate the energy crisis. However, infrared light, which constitutes nearly half of the solar energy, has not been effectively utilized yet. In this work, we discover a photogenerated charge transition mechanism in CuInS with intrinsic In antisite defects for synergistic utilization of full-spectrum photons.

Enhanced photo-fermentative hydrogen production by constructing Rhodobacter capsulatus-ZnO/ZnS hybrid system.

This study incorporated ZnO/ZnS nanoparticles with Rhodobacter capsulatus SB1003, forming a hybrid system to promote photo-fermentative hydrogen production. The results indicate that the material's photocatalytic activity and concentration significantly affected hydrogen yield. The addition of ZnO/ZnS exhibited a more significant auxiliary effect than ZnO and achieved an approximately 30% increase in hydrogen production compared to the control group.

Simultaneous production of CO and HO by paired electrolysis coupling CO reduction and water oxidation.

Here, a novel paired electrolysis system is constructed, where fluorine-doped tin oxide glass serves as the anode for the water oxidation reaction to produce hydrogen peroxide (HO), and cobalt phthalocyanine (CoPc)/carbon nanotube (CNT) loaded carbon paper as the cathode for CO reduction to generate CO. This system demonstrates a high overall energy efficiency of 34%, where a faradaic efficiency exceeding 90% for CO reduction and 60% for water oxidation to HO have been achieved, demonstrating significant energy savings of nearly 40% compared to the respective half-reaction systems.

Production of high calorific value hydrogen-rich combustible gas by supercritical water gasification of straw assisted by machine learning.

This article reveals the basic laws of straw supercritical water gasification (SCWG) and provides basic experimental data for the effective utilization of straw. The paper studied the impact of three operational conditions on the production of high-calorific value hydrogen-rich combustible gases through SCWG of straw within a quartz tube reactor. The findings reveal that elevated reaction temperatures, extended residence times, and reduced feedstock concentrations favor the SCWG of straw.

Selective and stable CO electroreduction at high rates via control of local HO/CO ratio.

Controlling the concentrations of HO and CO at the reaction interface is crucial for achieving efficient electrochemical CO reduction. However, precise control of these variables during catalysis remains challenging, and the underlying mechanisms are not fully understood. Herein, guided by a multi-physics model, we demonstrate that tuning the local HO/CO concentrations is achievable by thin polymer coatings on the catalyst surface.

Thermodynamic Model for Hydrogen Production from Rice Straw Supercritical Water Gasification.

Supercritical water gasification (SCWG) technology is highly promising for its ability to cleanly and efficiently convert biomass to hydrogen. This paper developed a model for the gasification of rice straw in supercritical water (SCW) to predict the direction and limit of the reaction based on the Gibbs free energy minimization principle. The equilibrium distribution of rice straw gasification products was analyzed under a wide range of parameters including temperatures of 400-1200 °C, pressures of 20-50 MPa, and rice straw concentrations of 5-40 wt%.

Recent progress on nickel phthalocyanine-based electrocatalysts for CO reduction.

The electrocatalytic reduction of CO to high-value fuels by renewable electricity is a sustainable strategy, which can substitute for fossil fuels and circumvent climate changes induced by elevated CO emission levels, making the rational design of versatile electrocatalysts highly desirable. Among all the electrocatalytic materials used in the CO reduction reaction, nickel phthalocyanine (NiPc)-based electrocatalysts have attracted considerable attention recently because of their high CO selectivity and catalytic activity. Herein, we review the latest advances in CO electroreduction to CO catalyzed by immobilized NiPc and its derivatives on diverse surfaces.

Supercritical CHOH-Triggered Isotype Heterojunction and Groups in g-CN for Enhanced Photocatalytic H Evolution.

The structure tuning of bulk graphitic carbon nitride (g-CN) is a critical way to promote the charge carriers dynamics for enhancing photocatalytic H-evolution activity. Exploring feasible post-treatment strategies can lead to effective structure tuning, but it still remains a great challenge. Herein, a supercritical CHOH (ScMeOH) post-treatment strategy (250-300 °C, 8.

RuSe and CoSe Nanoparticles Incorporated Nitrogen-Doped Carbon as Efficient Trifunctional Electrocatalyst for Zinc-Air Batteries and Water Splitting.

The development of affordable, highly active, and stable trifunctional electrocatalysts is imperative for sustainable energy applications such as overall water splitting and rechargeable Zn-air battery. Herein, we report a composite electrocatalyst with RuSe and CoSe hybrid nanoparticles embedded in nitrogen-doped carbon (RuSeCoSe/NC) synthesized through a carbonization-adsorption-selenylation strategy. This electrocatalyst is a trifunctional electrocatalyst with excellent hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR) activities.

Light energy utilization and microbial catalysis for enhanced biohydrogen: Ternary coupling system of triethanolamine-mediated Fe@C-Rhodobacter sphaeroides.

This study investigated the mediating effect of Triethanolamine on Fe@C-Rhodobacter sphaeroides hybrid photosynthetic system to achieve efficient biohydrogen production. The biocompatible Fe@C generates excited electrons upon exposure to light, releasing ferrum for nitrogenase synthesis, and regulating the pH of the fermentation environment. Triethanolamine was introduced to optimize the electron transfer chain, thereby improving system stability, prolonging electron lifespan, and facilitating ferrum corrosion.

Sulfur migration mechanism of pig manure in supercritical water: A combined experimental and DFT study.

Pig manure (PM) is a high concentration organic waste rich in sulfur, and its biofuel contains various sulfur-containing pollutants, which reduces the safety of the products. Supercritical water (SCW) can dissolve most organic matter, which is a technology worthy of further study. In order to reduce sulfur pollution in the process of PM resource utilization and better control the conversion path of sulfur, it is necessary to explore the migration mechanism of sulfur in the whole PM-SCW gasification process.

Pilot composite tubular bioreactor for outdoor photo-fermentation hydrogen production: From batch to continuous operation.

A novel 70 L composite tubular photo-bioreactor was constructed, and its photo-fermentation hydrogen production characteristics of batch and continuous modes were investigated with glucose as the substrate in an outdoor environment. In the batch fermentation stage, the hydrogen production rate peaked at 37.6 mL H/(L·h) accompanied by a high hydrogen yield of 7 mol H/mol glucose.

Mechanistic insights and catalytic enhancement of phenolic wastewater supercritical water gasification: A combined experiment and density functional theory study.

Supercritical water gasification technology provides a favorable technology to achieve pollution elimination and resource utilization of phenolic wastewater. In this study, the reaction mechanism of phenolic wastewater supercritical water gasification was investigated using a combination of experimental and computational methods. Five reaction channels were identified to elucidate the underlying pathway of phenol decomposition.

Decoupled electrolysis for hydrogen production and hydrazine oxidation via high-capacity and stable pre-protonated vanadium hexacyanoferrate.

Decoupled electrolysis for hydrogen production with the aid of a redox mediator enables two half-reactions operating at different rates, time, and spaces, which offers great flexibility in operation. Herein, a pre-protonated vanadium hexacyanoferrate (p-VHCF) redox mediator is synthesized. It offers a high reversible specific capacity up to 128 mAh g and long cycling performance of 6000 cycles with capacity retention about 100% at a current density of 10 A g due to the enhanced hydrogen bonding network.

Copper Vacancy and LSPR-Activated MXene Synergistically Enabling Selective Photoreduction CO to Acetate.

Photocatalytic CO conversion towards C fuels is a promising technology for simultaneously achieving carbon neutrality and alleviating the energy crisis. However, this strategy is inefficient due to the difficulty of both multi-electron transfer and C-C coupling during C formation. In this work, CuInS/MXene heterostructure with Cu vacancy is rationally designed by in situ hydrothermal synthesis.

Directional transformation and migration pathways of nitrogen during pig manure supercritical water gasification.

Nitrogen is a valuable nutrient element in pig manure. This work focuses on investigating the distribution, directional transformation, and migration pathways to facilitate the recovery of nitrogen from supercritical water gasification products. Results indicated that no nitrogen-containing gas was detected and 12.

d Band Links Frontier Orbitals and Charge Carrier Dynamics of Single-Atom Cocatalyst-Aided Photocatalytic H Production.

The Cu single-atom catalyst (SAC) supported on TiO exhibits outstanding efficacy in photocatalytic hydrogen evolution. The precise operational mechanism remains a subject of ongoing debate. The focus resides with the interplay linking heightened catalytic activity, dynamic valence state alterations of Cu atoms, and their hybridization with HO orbitals, manifested in catalyst color changes.

Fermi Level Pinning in Concentrated Light-Induced Band Edge Tuning Maximizes Photocatalytic Solar-to-Hydrogen Efficiency.

Here, we demonstrate a concentrated light-induced band edge tuning effect in photocatalytic hydrogen production. This band movement along with Femi level pinning leads to two distinct catalytic behaviors upon irradiation flux increase. Specifically, the concentration of the light promotes more long-lived carriers bound to the surface electronic states, progressively boosting energy conversion efficiency to a maximum value.

Growth characteristics and the mass transfer mechanism of single bubble on a photoelectrode at different electrolyte concentrations.

In the photoelectrochemical water splitting reaction, the bubble attached to the working electrode is an essential factor affecting the reaction resistance, current density and gas-liquid mass transfer. An experimental measurement system based on an electrochemical workstation synchronously coupled with a high-speed microscopic camera was proposed and used to systematically study the growth kinetics and mass transfer mechanism of single oxygen bubbles at different electrolyte concentrations (NaSO, 0.1-2.