Enhanced Electron–Hole Separation in Phosphorus-Coordinated Co Atom on g‑C₃N₄ toward Photocatalytic Overall Water Splitting

Revealing the decoration mode of g-C3N4 and understanding the physical mechanism of overall water splitting is important for the further improvement of the photocatalytic activity of g-C3N4-based materials. With core level shift and molecular dynamics simulations based on first-principles calculations, Co1(PHx)3 anchored on the triazine of g-C3N4 is determined as a stable single-atom catalyst with high efficiency for photocatalytic overall water splitting. The separated spin-polarized charge density distribution of valence-band maximum and conduction-band minimum states is beneficial for the long lifetime of photoexcited electrons and holes. An anchored Co single atom site is the active site for oxygen evolution reaction, and nitrogen atoms act as active sites for hydrogen evolution reaction. This new decoration mode of g-C3N4 opens a possible way to functionalize g-C3N4 on both triazine and void sites to realize the separation of OER and hydrogenation reaction by water splitting

Enhanced Electron–Hole Separation in Phosphorus-Coordinated Co Atom on g‑C₃N₄ toward Photocatalytic Overall Water Splitting

Revealing the decoration mode of g-C3N4 and understanding the physical mechanism of overall water splitting is important for the further improvement of the photocatalytic activity of g-C3N4-based materials. With core level shift and molecular dynamics simulations based on first-principles calculations, Co1(PHx)3 anchored on the triazine of g-C3N4 is determined as a stable single-atom catalyst with high efficiency for photocatalytic overall water splitting. The separated spin-polarized charge density distribution of valence-band maximum and conduction-band minimum states is beneficial for the long lifetime of photoexcited electrons and holes. An anchored Co single atom site is the active site for oxygen evolution reaction, and nitrogen atoms act as active sites for hydrogen evolution reaction. This new decoration mode of g-C3N4 opens a possible way to functionalize g-C3N4 on both triazine and void sites to realize the separation of OER and hydrogenation reaction by water splitting

Enhanced Electron–Hole Separation in Phosphorus-Coordinated Co Atom on g‑C₃N₄ toward Photocatalytic Overall Water Splitting

Revealing the decoration mode of g-C3N4 and understanding the physical mechanism of overall water splitting is important for the further improvement of the photocatalytic activity of g-C3N4-based materials. With core level shift and molecular dynamics simulations based on first-principles calculations, Co1(PHx)3 anchored on the triazine of g-C3N4 is determined as a stable single-atom catalyst with high efficiency for photocatalytic overall water splitting. The separated spin-polarized charge density distribution of valence-band maximum and conduction-band minimum states is beneficial for the long lifetime of photoexcited electrons and holes. An anchored Co single atom site is the active site for oxygen evolution reaction, and nitrogen atoms act as active sites for hydrogen evolution reaction. This new decoration mode of g-C3N4 opens a possible way to functionalize g-C3N4 on both triazine and void sites to realize the separation of OER and hydrogenation reaction by water splitting

Enhanced Electron–Hole Separation in Phosphorus-Coordinated Co Atom on g‑C₃N₄ toward Photocatalytic Overall Water Splitting

Revealing the decoration mode of g-C3N4 and understanding the physical mechanism of overall water splitting is important for the further improvement of the photocatalytic activity of g-C3N4-based materials. With core level shift and molecular dynamics simulations based on first-principles calculations, Co1(PHx)3 anchored on the triazine of g-C3N4 is determined as a stable single-atom catalyst with high efficiency for photocatalytic overall water splitting. The separated spin-polarized charge density distribution of valence-band maximum and conduction-band minimum states is beneficial for the long lifetime of photoexcited electrons and holes. An anchored Co single atom site is the active site for oxygen evolution reaction, and nitrogen atoms act as active sites for hydrogen evolution reaction. This new decoration mode of g-C3N4 opens a possible way to functionalize g-C3N4 on both triazine and void sites to realize the separation of OER and hydrogenation reaction by water splitting

Enhanced Electron–Hole Separation in Phosphorus-Coordinated Co Atom on g‑C₃N₄ toward Photocatalytic Overall Water Splitting

Revealing the decoration mode of g-C3N4 and understanding the physical mechanism of overall water splitting is important for the further improvement of the photocatalytic activity of g-C3N4-based materials. With core level shift and molecular dynamics simulations based on first-principles calculations, Co1(PHx)3 anchored on the triazine of g-C3N4 is determined as a stable single-atom catalyst with high efficiency for photocatalytic overall water splitting. The separated spin-polarized charge density distribution of valence-band maximum and conduction-band minimum states is beneficial for the long lifetime of photoexcited electrons and holes. An anchored Co single atom site is the active site for oxygen evolution reaction, and nitrogen atoms act as active sites for hydrogen evolution reaction. This new decoration mode of g-C3N4 opens a possible way to functionalize g-C3N4 on both triazine and void sites to realize the separation of OER and hydrogenation reaction by water splitting

Synergistic Effect of Titanate-Anatase Heterostructure and Hydrogenation-Induced Surface Disorder on Photocatalytic Water Splitting

Black TiO₂ obtained by hydrogenation has attracted enormous attention due to its unusual photocatalytic activity. In this contribution, a novel photocatalyst containing both a titanate–anatase heterostructure and a surface disordered shell was in situ synthesized by using a one-step hydrogenation treatment of titanate nanowires at ambient pressure, which exhibited remarkably improved photocatalytic activity for water splitting under simulated solar light. The as-hydrogenated catalyst with a heterostructure and a surface disordered shell displayed a high hydrogen production rate of 216.5 μmol·h^–1, which is ∼20 times higher than the Pt-loaded titanate nanowires lacking of such unique structure. The in situ-generated heterostructure and hydrogenation-induced surface disorder can efficiently promote the separation and transfer of photoexcited electron–hole pairs, inhibiting the fast recombination of the generated charge carriers. A general synergistic effect of the heterostructure and the surface disordered shell on photocatalytic water splitting is revealed for the first time in this work, and the as-proposed photocatalyst design and preparation strategy could be widely extended to other composite photocatalytic systems used for solar energy conversion

Enhanced Electron–Hole Separation in Phosphorus-Coordinated Co Atom on g‑C₃N₄ toward Photocatalytic Overall Water Splitting

Revealing the decoration mode of g-C3N4 and understanding the physical mechanism of overall water splitting is important for the further improvement of the photocatalytic activity of g-C3N4-based materials. With core level shift and molecular dynamics simulations based on first-principles calculations, Co1(PHx)3 anchored on the triazine of g-C3N4 is determined as a stable single-atom catalyst with high efficiency for photocatalytic overall water splitting. The separated spin-polarized charge density distribution of valence-band maximum and conduction-band minimum states is beneficial for the long lifetime of photoexcited electrons and holes. An anchored Co single atom site is the active site for oxygen evolution reaction, and nitrogen atoms act as active sites for hydrogen evolution reaction. This new decoration mode of g-C3N4 opens a possible way to functionalize g-C3N4 on both triazine and void sites to realize the separation of OER and hydrogenation reaction by water splitting

Tunable Band Structures of Heterostructured Bilayers with Transition-Metal Dichalcogenide and MXene Monolayer

Forming bilayer or multilayer heterostructures via interlayer van der Waals interactions is a superior preparation strategy for two-dimensional heterojunctions. In this work, by employing density functional theory computations, we investigated heterostructured bilayers of transition-metal dichalcogenides (TMDs) (including MoS₂, WS₂, MoSe₂, and WSe₂) and MXene (exemplified by Sc₂CF₂) monolayer. All TMD and Sc₂CF₂ materials are hexagonal with little mismatch. Compared with separate TMD and Sc₂CF₂ monolayers, TMD–Sc₂CF₂ bilayers can be tuned to indirect semiconductors with the band gaps of 0.13–1.18 eV; more importantly, they are type-II heterostructures with the valence band maximum and conduction band minimum located at Sc₂CF₂ and TMDs, respectively. Stretching or compressing would reduce or enlarge the band gaps of the heterostructures, respectively. The tunable band structures make TMD–Sc₂CF₂ bilayers pomising candidates for electronic device applications

Single Mo₁(Cr₁) Atom on Nitrogen-Doped Graphene Enables Highly Selective Electroreduction of Nitrogen into Ammonia

Searching for new types of electrocatalysts with high stability, activity, and selectivity is essential for the production of ammonia via electroreduction of nitrogen. Using density functional theory (DFT) calculations, we explore the stability of single metal atoms (M1) supported on nitrogen-doped graphene (N3-G); the competitive adsorption of dinitrogen and hydrogen; and the potential competition of first dinitrogen protonation and hydrogen adsorption on metal sites. Consequently, we identify Mo1/N3-G and Cr1/N3-G as candidate electrocatalysts for nitrogen reduction reaction (NRR). The theoretically predicted selectivities (overpotentials) are 40% (0.34 V) and 100% (0.59 V) on Mo1/N3-G and Cr1/N3-G, respectively. The electroreduction of nitrogen proceeds via distal-to-alternating hybrid mechanism with two spectator dinitrogen molecules. The high stability, high selectivity to ammonia, and relatively low overpotentials for NRR suggest Mo1(Cr1)/N3-G as the most promising electrocatalyst among those studied for electroreduction of nitrogen

Detecting a Molecule−Surface Hybrid State by an Fe-Coated Tip with a Non-s-Like Orbital

A tungsten tip and an iron-coated tungsten tip were used to investigate cobalt phthalocyanine molecules absorbed on a Au(111) surface. Similar STM images but different STS curves were obtained above the central part of the molecules. Theoretical analysis points out that the delocalized orbital of ligands hybridized with the Au surface at 0.4 eV below Fermi level can be detected and enhanced with an iron-coated tungsten tip due to the extended spatial distribution of the frontier orbital in the tip. As the spatial distribution of the frontier orbital in the tungsten tip is localized, the hybrid state cannot be detected above the central part of the molecule. These results indicate that the appropriateness of selection and preparation of the STM tip can probe richer chemistry and physics on surfaces