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.

Tuning Transition Metal 3d Spin state on Single-atom Catalysts for Selective Electrochemical CO Reduction.

Tuning transition metal spin states potentially offers a powerful means to control electrocatalyst activity. However, implementing such a strategy in electrochemical CO reduction (COR) is challenging since rational design rules have yet to be elucidated. Here we show how the addition of P dopants to a ferromagnetic element (Fe, Co, and Ni) single-atom catalyst (SAC) can shift its spin state.

Activating inert non-defect sites in Bi catalysts using tensile strain engineering for highly active CO electroreduction.

Bi-defect sites are highly effective for CO reduction (CORR) to formic acid, yet most catalytic surfaces predominantly feature inert, non-defective Bi sites. To overcome this limitation, herein, tensile strain is introduced on wholescale non-defective Bi sites. Under rapid thermal shock, the Bi-based metal-organic framework (Bi-MOF-TS) shows weakened Bi-O bonds and produced tiny Bi clusters.

All-round enhancement induced by oxophilic single Ru and W atoms for alkaline hydrogen oxidation of tiny Pt nanoparticles.

Anion exchange membrane fuel cells (AEMFCs) are one of the ideal energy conversion devices. However, platinum (Pt), as the benchmark catalyst for the hydrogen oxidation reaction (HOR) of AEMFCs anodes, still faces issues of insufficient performance and susceptibility to CO poisoning. Here, we report the Joule heating-assisted synthesis of a small sized RuPt single-atom alloy catalyst loaded on nitrogen-doped carbon modified with single W atoms (s-RuPt@W/NC), in which the near-range single Ru atoms on the RuPt nanoparticles and the long-range single W atoms on the support simultaneously modulate the electronic structure of the active Pt-site, enhancing alkaline HOR performance of s-RuPt@W/NC.

Pt/IrO enables selective electrochemical C-H chlorination at high current.

Employing electrochemistry for the selective functionalization of liquid alkanes allows for sustainable and efficient production of high-value chemicals. However, the large potentials required for C(sp)-H bond functionalization and low water solubility of such alkanes make it challenging. Here we discover that a Pt/IrO electrocatalyst with optimized Cl binding energy enables selective generation of Cl free radicals for C-H chlorination of alkanes.

Balancing Activity and Selectivity in Two-Electron Oxygen Reduction through First Coordination Shell Engineering in Cobalt Single Atom Catalysts.

The electrochemical two-electron oxygen reduction reaction (2e ORR) offers a potentially cost-effective and eco-friendly route for the production of hydrogen peroxide (HO). However, the competing 4e ORR that converts oxygen to water limits the selectivity towards hydrogen peroxide. Accordingly, achieving highly selective HO production under low voltage conditions remains challenging.

Organic Molecule Functionalization Enables Selective Electrochemical Reduction of Dilute CO Feedstock.

The electrochemical conversion of low-concentration CO feedstock to value-added chemicals and fuels is a promising pathway for achieving direct valorization of waste gas streams. However, this is challenging due to significant competition from the hydrogen evolution reaction (HER) and lowered CO reduction (COR) kinetics as compared to systems that employ pure CO. Here we show that terephthalic acid (TPA) functionalization can boost selectivity towards COR and suppress HER over a range of catalysts including Bi, Cu and Zn.

Hexa-atom Pt Catalyst Fabricated by a Ligand Engineering Strategy for Efficient Hydrogen Oxidation Reaction.

Atomically precise supported nanocluster catalysts (APSNCs), which feature exact atomic composition, well-defined structures, and unique catalytic properties, offer an exceptional platform for understanding the structure-performance relationship at the atomic level. However, fabricating APSNCs with precisely controlled and uniform metal atom numbers, as well as maintaining a stable structure, remains a significant challenge due to uncontrollable dispersion and easy aggregation during synthetic and catalytic processes. Herein, we developed an effective ligand engineering strategy to construct a Pt nanocluster catalyst stabilized on oxidized carbon nanotubes (Pt/OCNT).

Dilute RuCo Alloy Synergizing Single Ru and Co Atoms as Efficient and CO-Resistant Anode Catalyst for Anion Exchange Membrane Fuel Cells.

Ruthenium (Ru) is considered a promising candidate catalyst for alkaline hydroxide oxidation reaction (HOR) due to its hydrogen binding energy (HBE) like that of platinum (Pt) and its much higher oxygenophilicity than that of Pt. However, Ru still suffers from insufficient intrinsic activity and CO resistance, which hinders its widespread use in anion exchange membrane fuel cells (AEMFCs). Here, we report a hybrid catalyst (RuCo)/N-CNT consisting of dilute RuCo alloy nanoparticles and atomically single Ru and Co atoms on N-doped carbon nanotubes The catalyst exhibits a state-of-the-art activity with a high mass activity of 7.

Enhanced Carbon-Carbon Coupling at Interfaces with Abrupt Coordination Number Changes.

Cu-catalyzed electrochemical CO reduction reaction (CORR) produces multi-carbon (C) chemicals with considerable selectivities and activities, yet required high overpotentials impede its practical application. Here, we design interfaces with abrupt coordination number (CN) changes that greatly reduce the applied potential for achieving high C Faradaic efficiency (FE). Encouraged by the mechanistic finding that the coupling between *CO and *CO(H) is the most probable C-C bond formation path, we use CuO- and Cu-phthalocyanine-derived Cu (OD-Cu and PD-Cu) to build the interface.

Promoting CO Electroreduction to Multi-Carbon Products by Hydrophobicity-Induced Electro-Kinetic Retardation.

Advancing the performance of the Cu-catalyzed electrochemical CO reduction reaction (CO RR) is crucial for its practical applications. Still, the wettable pristine Cu surface often suffers from low exposure to CO , reducing the Faradaic efficiencies (FEs) and current densities for multi-carbon (C ) products. Recent studies have proposed that increasing surface availability for CO by cation-exchange ionomers can enhance the C product formation rates.

Surface passivation for highly active, selective, stable, and scalable CO electroreduction.

Electrochemical conversion of CO to formic acid using Bismuth catalysts is one the most promising pathways for industrialization. However, it is still difficult to achieve high formic acid production at wide voltage intervals and industrial current densities because the Bi catalysts are often poisoned by oxygenated species. Herein, we report a BiS nanowire-ascorbic acid hybrid catalyst that simultaneously improves formic acid selectivity, activity, and stability at high applied voltages.

Tuning Active Metal Atomic Spacing by Filling of Light Atoms and Resulting Reversed Hydrogen Adsorption-Distance Relationship for Efficient Catalysis.

Precisely tuning the spacing of the active centers on the atomic scale is of great significance to improve the catalytic activity and deepen the understanding of the catalytic mechanism, but still remains a challenge. Here, we develop a strategy to dilute catalytically active metal interatomic spacing (d) with light atoms and discover the unusual adsorption patterns. For example, by elevating the content of boron as interstitial atoms, the atomic spacing of osmium (d) gradually increases from 2.

Constrained C adsorbate orientation enables CO-to-acetate electroreduction.

The carbon dioxide and carbon monoxide electroreduction reactions, when powered using low-carbon electricity, offer pathways to the decarbonization of chemical manufacture. Copper (Cu) is relied on today for carbon-carbon coupling, in which it produces mixtures of more than ten C chemicals: a long-standing challenge lies in achieving selectivity to a single principal C product. Acetate is one such C compound on the path to the large but fossil-derived acetic acid market.