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We present in this paper the stability of SWCNT hybrid systems with Py molecules. vdW type interactions are therefore the main interaction mechanism between encapsulated molecules and nanotubes, and the simplest model to describe these interactions is the Lennard-Jones potential. We have therefore performed energy minimization calculations on hybrid SWCNTs in a very wide range of diameters and of all chirality using the Lennard-Jones potential. The structure of the carbon nanotube is obtained from the winding of graphene on itself to form a hollow cylinder described by the pair of integers (n, m) entirely determining its structural characteristics, while the optimization of the geometry of the Py molecule is obtained by SIESTA using the exchange–correlation functional LDA. After minimisation, an approach that combines density functional theory, molecular mechanics, bond polarizability model, and spectral moment's method has been used to compute Raman spectra. Two types of vibration modes of SWCNTs attract our attention. Initially, the modifications of the modes of Py after encapsulation will be analyzed. In the following discussion, we examine how the vibrational properties of single-walled carbon nanotubes (SWCNTs) are affected by encapsulation, specifically in relation to the RBM and tangential modes. Our analysis of the Raman active modes supports the notion that the structural integrity of the SWCNTs remains intact and indicates the occurrence of a charge transfer between the Py molecules and SWCNTs. This charge transfer depends on the geometric position of Py in the SWCNT. [ABSTRACT FROM AUTHOR]

[Display omitted] • 1D MWO 4 (M = Mn, Co, Cd) nanomaterials were synthesized by electrospinning method. • CoWO 4 nanotubes exhibited superior efficiency in degrading BPA under UV–Vis–NIR light. • The wide-spectrum responses mechanism for MWO 4 (M = Mn, Co, Cd) were explained by DFT. Broadening the absorption region to near-infrared (NIR) light is critical for the photocatalysis due to the larger proportion and stronger penetration of NIR light in solar energy. In the present paper, one-dimensional (1D) MWO 4 (M = Mn, Co, and Cd) materials synthesized by electrospinning technique, were studied by combining the density functional theory (DFT) with experiment results, which possessed the enhanced light absorption capability within the range of 200–2000 nm. It was proved that in the ultraviolet–visible (UV–Vis) region, the absorption bands of CoWO 4 and MnWO 4 samples were attributed to the metal-to-metal charge transfer mechanism, while the absorption of CdWO 4 sample may be referable to the ligand-to-metal charge transfer mechanism. In the near-infrared (NIR) region, the absorption of CoWO 4 and MnWO 4 primarily originated from the d-d orbital transitions of Mn2+ and Co2+. The photocatalytic experimental results showed that the degradation rates for bisphenol A (BPA) over CoWO 4 , MnWO 4 , and CdWO 4 photocatalysts under UV–Vis/NIR light irradiation for 140 min/12 h were 78.8 %/75.9 %, 23.8 %/21.3 %, 12.8 %/8.7 %, respectively. This research offers the novel insights into the precise construction of tungstate catalytic systems and contributes to the advancement of UV–Vis–NIR full spectrum photocatalytic technology, and lays a foundation for a cleaner and more environmental-friendly future. [ABSTRACT FROM AUTHOR]

The novel S-scheme heterostructure shows its superiority in photocatalysis due to its high efficiency of charge transfer. In this paper, we compared the mechanical, electronic, optical and transport properties of two different contact modes of heterostructure structures of MoSe 2 /Janus PtSSe and their applications in photocatalytic water splitting through density functional theory. The results show that the charge transfer of MoSe 2 /SePtS heterostructures occurs between layers. On the contrary, the charge separation of MoSe 2 /SPtSe heterostructures is significant, and there are internal electric fields and suitable band arrangements at the interface from MoSe 2 to SPtSe direction, forming S-scheme photocatalysts. Compared with the MoSe 2 /SePtS heterostructure, the MoSe 2 /SPtSe heterostructure has higher carrier mobility. Furthermore, the MoSe 2 /SPtSe heterostructure has good light absorption in the visible range, and the solar-to-hydrogen (STH) efficiency is as high as 7.97%. Gibbs free energy calculation shows that the overpotential η OER = 1.63 V (pH = 0) decreases to η OER = 1.11 V(pH = 7) with the increase of pH value. We expect that our results can provide valuable insights into the rational design of efficient heterostructure in photocatalytic water splitting systems. [Display omitted] • MoSe 2 /SPtSe heterostructure with high carrier mobility. • The existence of charge transfer in the MoSe 2 /SPtSe heterostructure is advantageous. • MoSe 2 /SPtSe heterostructure is a S-scheme photocatalyst for water splitting. • The ηOER of MoSe 2 /SPtSe heterojunction decreased with the increase of pH. • MoSe 2 /SPtSe heterostructure has ultra-high STH efficiency (7.79%). [ABSTRACT FROM AUTHOR]

The capacity to manipulate magnetization in 2D dilute magnetic semiconductors (2D‐DMSs) using light, specifically in magnetically doped transition metal dichalcogenide (TMD) monolayers (M‐doped TX2, where M = V, Fe, and Cr; T = W, Mo; X = S, Se, and Te), may lead to innovative applications in spintronics, spin‐caloritronics, valleytronics, and quantum computation. This Perspective paper explores the mediation of magnetization by light under ambient conditions in 2D‐TMD DMSs and heterostructures. By combining magneto‐LC resonance (MLCR) experiments with density functional theory (DFT) calculations, we show that the magnetization can be enhanced using light in V‐doped TMD monolayers (e.g., V‐WS2, V‐WSe2). This phenomenon is attributed to excess holes in the conduction and valence bands, and carriers trapped in magnetic doping states, mediating the magnetization of the semiconducting layer. In 2D‐TMD heterostructures (VSe2/WS2, VSe2/MoS2), the significance of proximity, charge‐transfer, and confinement effects in amplifying light‐mediated magnetism is demonstrated. We attributed this to photon absorption at the TMD layer that generates electron–hole pairs mediating the magnetization of the heterostructure. These findings will encourage further research in the field of 2D magnetism and establish a novel design of 2D‐TMDs and heterostructures with optically tunable magnetic functionalities, paving the way for next‐generation magneto‐optic nanodevices. [ABSTRACT FROM AUTHOR]

Cyclo[18]carbon has received considerable attention thanks to its novel geometric configuration and special electronic structure. Superalkalis have low ionization energy. Doping a superalkali in cyclo[18]carbon is an effective method to improve the optical properties of the system because considerable electron transfer occurs. In this paper, the geometry, bonding properties, electronic structure, absorption spectrum, and nonlinear optical (NLO) properties of superalkaline M 3O (M = Li, Na)-doped cyclo[18]carbon were studied by using density functional theory. M 3O and the C18 rings are not coplanar. The C18 ring still exhibits alternating long and short bonds. The charge transfer between M 3O and C18 forms stable [ M 3O]+[C18]− ionic complexes. C18 M 3O (M = Li, Na) shows striking optical nonlinearity, i.e., their first- and second-order hyperpolarizability (β vec and γ ||) increase considerably at λ = 1907 nm and 1460 nm. [ABSTRACT FROM AUTHOR]

The insulating gas and contacts in the arc extinguishing chamber of high‐voltage circuit breakers are the focus of research. In practical applications, the gas may react with the surface of the contacts. In this paper, C5F10O environmental friendly insulating gas, which has one of the potential alternatives, is selected as the research object. The compatibility of C5F10O and its decomposition products with CuW contacts was studied. This article uses the Dmol3 program based on density functional theory. The adsorption energy, transfer charge, and density of electronic states of C5F10O and selected typical decomposition products on the Cu (111) surface and Cu‐W surface were calculated, respectively. It was found that the original CuW metal properties were not changed before and after adsorption. The carbonyl O atom in C5F10O is easily adsorbed on the top of the Cu (111) surface, forming a stable CuO bond, which belongs to chemical adsorption. The interaction of the other three adsorption sites is weaker than that of the top site adsorption, which belongs to physical adsorption. C5F10O exhibits more active charge transfer and forms active W‐O chemical bonds when adsorbed on CuW surfaces than SF6. C5F10O has poorer compatibility with CuW alloy than SF6. C2F4 and C3F6 in the decomposition gas are chemically adsorbed on the Cu‐W surface. CO2, CF4, C2F6, and C3F8 do not form chemical bonds on the CuW surface. The adsorption stability of COF2 is weaker than that of CF4, C2F6, and C3F8. Compared with SF6 adsorption, the compatibility of C5F10O and CO2 on the surface of CuW contact is inferior to that of Cu contact. CF4, C2F6, C3F8, and COF2 in the decomposition gas can be compatible with the surface of the CuW contact. C2F4 and C3F6 cannot be well compatible with the surface of CuW contacts. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

[Display omitted] • Doping B, N, P can enhance the electrical conductivity and adsorption properties of GeC monolayers. • The stability of the three adsorption structures was in the order of C2H2 > CH4, and the increase of Qt and the decrease of bandgap indicated that the conductivity of the adsorbed system was improved. • it was shown that the monolayer of P-GeC has the most optimal adsorption behaviour and reusability for C2H2. In this paper, the stability, electronic structure and optical properties of monolayer GeC, B, N and P doped GeC systems are systematically investigated based on the first principles of density functional theory. The results show that the results show that the intrinsic GeC monolayer has a weak adsorption capacity for CH 4 and C 2 H 2 , which is unfavourable for the sensing and trapping of CH 4 and C 2 H 2 gases. Based on calculated adsorption distance, adsorption energy and charge transfer, we find that P-GeC monolayer is the most sensitive to CH 4 and C 2 H 2 molecules, and the most of gas molecules act as acceptors to gain electrons from GeC monolayer. The adsorption energy of CH 4 is smaller than that of C 2 H 2 gas molecule, which implies that C 2 H 2 is more easily desorbed from P-GeC. Moreover, the work function changes significantly when gas molecules adsorbed on B, N, P-GeC, and Recovery times indicate that B, N and P doped GeC monolayers are more selective and sensitive to C 2 H 2 molecules compared to CH4 molecules. The research work aims to provide a theoretical basis for the application of GeC-based gas sensors, and P-doped GeC monolayers can be used as candidate materials for C 2 H 2 gas sensing and trapping. [ABSTRACT FROM AUTHOR]

Ruthenium(II) polypyridine compounds often luminesce, with ligand-dependant lifetimes. This is the third in a series of papers devoted to finding orbital-based luminescence indices (LI) for predicting luminescence lifetimes. The third attempt (LI3) was based upon a frontier molecular orbital (FMO) like estimate of the height of the barrier to conversion from an initial phosophorescent triplet metal-ligand charge transfer ( 3 MLCT) state to a nonluminescent triplet metal-centered ( 3 MC) state which decays nonradiatively. A linear correlation was found between LI3 and extracted empirical average 3 MLCT → 3 MC transition state (TS) barrier heights (E a v e s) which were not believed to be quantitative but which were believed to capture the trends in the true barrier heights correctly. As it is known that E a v e is a large underestimate of the true 3 MLCT → 3 MC TS barrier height in the case of the tris bipyridine ruthenium(II) cation { [Ru(bpy) 3 ] 2 + }, but accurate TS barrier heights are difficult to obtain experimentally, it was judged useful to verify the ideas used to derive the LI3 index in the present work by calculating the energetics of the gas-phase 3MLCT → 3MC reaction for a series of ruthenium(II) tris bipyridine complexes using the same density functional and basis sets used in calculating LI3. Specifically, four closely-related bipyridine complexes { [Ru(N ∧ N) 3 ] 2 + with N ∧ N = bpy (6), 4,4'-dm-bpy (70), 4,4'-dph-bpy (73), and 4,4'-DTB-bpy (74) } were used for these calculations. In the process, we examined the gas-phase trans dissociation mechanism in greater detail than has been previously done and uncovered a two part mechanism. In the first part, the electron is transferred to a single ligand rather than symmetrically to all three ligands. It is the two Ru-N bonds to this ligand which are equally elongated in the transition state. The intrinsic reaction coordinate then continues down a ridge in hyperspace and bifurcates into one of two symmetry-equivalent 3 MC structures with elongated trans bonds. Interestingly, no significant difference is found for the TS barriers for the four complexes treated here. Instead, LI3 is linearly correlated with the energy difference Δ E = E ( 3 MLCT) − E ( 3 MC) , different from what was originally intended but still consistent with the FMO arguments underlying the derivation of LI3. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, we performed theoretical studies on the twelve D-A-π-A type organic dyes (G-1 ~ G-3, M-1 ~ M-3, J-1 ~ J-3, and S-1 ~ S-3) with 9-phenylcarbazole as the electron donor in anticipation of the application of these dyes in dye-sensitized solar cells (DSSCs). DFT and TD-DFT methods are applied to investigate in detail the molecular geometries, frontier molecular orbitals (FMOs), absorption spectra, charge density difference (CDD), and transition density matrix (TDM) of several dyes. The results show that the M-series (M-1 ~ M-3) dyes have the largest dihedral angles between the electron donor and the auxiliary acceptor and also has the largest energy gaps in HOMO–LUMO orbitals, which greatly reduces the charge transfer efficiency. Finally, the UV–Vis absorption spectra inferred that the anchoring groups modified with o-nitrobenzoic acid (G-3, M-3, J-3, S-3) can red-shift the absorption peaks of the dyes, which results in higher light-harvesting efficiency and improves the power conversion efficiency of DSSCs. Overall, all of these dyes contribute to the improvement of photovoltaic power conversion efficiency and have potential for application in DSSCs devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • High-mass loading CoO@NiCo-LDH was prepared from ZIF-67 self-sacrificing template. • Irregular electrode surfaces of 3D nanochannels enable rapid reaction kinetics. • Core-shell structure enhances LDH's conductivity and Faradaic activity. • A simple one-step hydrothermal method to prepare the High-mass loading FeNi-S anode. The rapidly growing market of portable and wearable smart electronics has created strong interest in flexible electrode materials with high specific capacitance and fast charging/discharging properties. However, high mass-specific capacitance active materials are often limited by the low areal mass-loading required. High areal capacity electrodes can make more efficient use of the limited internal space of these miniature devices by minimizing the volume and weight taken by current collectors and separators. Herein, a method is proposed to prepare a nickel–cobalt layered double hydroxide binder-free cathode on flexible carbon cloth with a mass loading of 20 mg cm−2. This core–shell hybrid structure prepared using a MOF self-sacrificing template, achieves a high energy density using thick electrodes while improving their slow kinetics by enhancing both the ion diffusion process and charge transfer dynamics. The areal capacitance reaches a staggering 4.42 mAh cm−2 (31.79 F cm−2) at a current density of 8 mA cm−2. Furthermore, a one-step hydrothermal method to prepare the FeNi-S anode (1.67 mAh cm−2, 2 mA cm−2) is proposed. Upon assembling with the gel electrolyte, this flexible device possesses an impressive energy density of 3.29 mW h cm−2 (3 mW cm−2). It can readily supply energy to watches, wireless e-paper, LEDs, and can be anticipated to be widely used in next-generation high-performance portable and wearable devices. [ABSTRACT FROM AUTHOR]

• The evolution of the structures for Mg 2 Bn0/– (n = 1–12) clusters has be elucidated. • The corresponding ground state structures are determined. • The local stable ground state structure is found. • The properties of electrons and bonds of the most stable isomers are discussed. In this paper, a global search for the lowest energy structure of Mg 2 B n 0/- (n = 1–12) clusters is performed based on Density functional theory combined with the particle swarm optimization algorithm program CALYPSO. The geometry, stability, charge transfer, and bonding properties of the clusters were analyzed at the B3LYP/def2-tzvp level. Then Mg 2 B 8 with high symmetry D 4h was found to be the magic numbers cluster among them. The doped clusters Mg 2 B n 0/− were compared with the pure boron clusters B n+2 0/− (n = 1–12) at the same level. The following results are obtained: as the number of boron atoms increases, the boron clusters doped with Mg atoms change from a two-dimensional planar or quasi-plane structure to a three-dimensional structure. The doped magnesium atoms are always positively charged in the convex capped position. And the doping of Mg atoms drives the overall stabilization of the boron clusters and makes the clusters more compact. There is a large amount of charge transfer between the Mg atom and the B atom, and the main orbitals involved are the S and p orbitals. There are strong interactions between the two atoms of boron and magnesium. Through the analysis of the bonding properties, it was found that the s-p hybridization mode between Mg B is the main reason for the enhanced cluster stability. [Display omitted] [ABSTRACT FROM AUTHOR]

• The evolution of the structures for Mg 2 Bn0/– (n = 1–12) clusters has be elucidated. • The corresponding ground state structures are determined. • The local stable ground state structure is found. • The properties of electrons and bonds of the most stable isomers are discussed. In this paper, a global search for the lowest energy structure of Mg 2 B n 0/- (n = 1–12) clusters is performed based on Density functional theory combined with the particle swarm optimization algorithm program CALYPSO. The geometry, stability, charge transfer, and bonding properties of the clusters were analyzed at the B3LYP/def2-tzvp level. Then Mg 2 B 8 with high symmetry D 4h was found to be the magic numbers cluster among them. The doped clusters Mg 2 B n 0/− were compared with the pure boron clusters B n+2 0/− (n = 1–12) at the same level. The following results are obtained: as the number of boron atoms increases, the boron clusters doped with Mg atoms change from a two-dimensional planar or quasi-plane structure to a three-dimensional structure. The doped magnesium atoms are always positively charged in the convex capped position. And the doping of Mg atoms drives the overall stabilization of the boron clusters and makes the clusters more compact. There is a large amount of charge transfer between the Mg atom and the B atom, and the main orbitals involved are the S and p orbitals. There are strong interactions between the two atoms of boron and magnesium. Through the analysis of the bonding properties, it was found that the s-p hybridization mode between Mg B is the main reason for the enhanced cluster stability. [Display omitted] [ABSTRACT FROM AUTHOR]

• CuO-NiO complex metal oxides catalyzed glycerol production of lactic acid. • Significant heterogeneous junctions were observed by HRTEM. • CuO1NiO2 has excellent catalytic activity (90.08 % lactic acid yield). • DFT calculations revealed that Cu-Ni composite metal oxides are more likely to adsorb glycerol. • The differential charge density verifies that the formation of heterojunctions promotes charge transport and enhances electronic synergies. One of the most essential techniques to achieve effective usage of the principal by-product (glycerol) in the manufacturing of biodiesel is catalytic conversion of glycerol to lactic acid. In this paper, CuO-NiO composite metal oxides with different Cu/Ni molar ratios were prepared by co-precipitation method to catalyze the conversion of glycerol to lactic acid in alkaline medium. By using XRD, SEM, TEM, BET, XPS, and H 2 -TPR characterisation, the catalysts' crystalline phase, shape, and performance were assessed. The results show that the electronic synergy of CuO-NiO composite metal oxides plays a positive role in catalyzing the conversion of glycerol to lactic acid. The production of lactic acid might reach 90.08 % when Cu/Ni molar ratio (CuO1NiO2) and reaction conditions are optimum. In conjunction with the analysis using Density Functional Theory: due to the formation of heterojunctions in CuO1NiO2 the formation of good contacts between the atoms at the CuO and NiO interfaces is conducive to promoting charge transfer and electron mobility, thus enhancing the synergistic effect of electron transfer. Meanwhile, DFT calculations revealed that the Cu-Ni composite metal oxides had stronger adsorption energy for glycerol, which favored the bonding of glycerol on their surfaces. The prepared CuO-NiO composite metal oxides were used to catalyze the conversion of glycerol to lactic acid. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • CF S,N /CN nanocomposites with strong π-conjugation is successfully prepared. • The prepared CF S,N /CN nanocomposites exhibit ultrahigh H 2 O 2 production rate. • CF S,N acts as ultrafast electronic mediate for directional electron transport. • The π-conjugation is convenient for interfacial electron redistribution. • The π-conjugation effect on CN and CF/CF S,N is illustrated by DFT calculation. Heterojunction engineering of graphitic carbon nitride (CN) was considered as a facile and efficient approach to boost photocatalytic hydrogen peroxide (H 2 O 2) generation. However, photocatalytic H 2 O 2 generation over CN/carbon fiber (CF) heterojunction is still challenging due to the rapid transfer and recombination of photogenerated charges. To solve this problem, a novel sulfur/nitrogen-self-doped carbon fibers (CF S,N), derived from poly(2-acrylamido-2-methylpropane sulfonic) (AMPS)-grafted cellulose nanofibers as an efficient electron mediate was herein engineered onto CN skeleton (CN/CF S,N) for achieving high-performance H 2 O 2 production. The as-synthesized CN/CF S,N nanocomposites exhibit an efficient H 2 O 2 production rate of 1.31 mmol∙L-1∙h−1, which is 6.0 and 1.3 times higher than that of pure CN (0.22 mmol∙L-1∙h−1) and CN/CF (0.99 mmol∙L-1∙h−1), respectively, which also significantly outperforms recently-reported CN-based photocatalysts. Based on the experimental results and density functional theory (DFT) simulation, the CF S,N with S/N-doped carbon can act as an ultrafast electronic mediate for directional electron transport, which facilitates interfacial carrier transfer between CN and CF S,N. More importantly, beneficially from the interfacial electron redistribution via the π-conjugation of CF S,N , the molecular oxygen (O 2) is highly activated to orderly drive sequential one-electron two-step O 2 -to-H 2 O 2 conversion. This study presents a promising design of cellulose-derived carbon, which efficiently regulates the charge transfer and separation of CN-based photocatalysts for significantly enhanced H 2 O 2 production. [ABSTRACT FROM AUTHOR]