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This investigation highlights the significant impact of asymmetric Janus Zr2COT (T = F, Cl, Br, I) monolayers on enhancing the hydrogen evolution reaction (HER) performance. Employing density functional theory (DFT), our research demonstrates that introducing asymmetric functional groups into Zr2COT structures effectively tailors their electronic properties, leading to a marked improvement in HER activity. This structural innovation notably reduces the hydrogen adsorption Gibbs free energy (ΔGH*) from 0.877 eV for the symmetric Zr2CO2 to below 0.2 eV for the Janus Zr2COT configurations, with Zr2COBr and Zr2COI achieving exceptionally low ΔGH* values of 0.045 and −0.042 eV, respectively, at a hydrogen coverage of 1/4. The monolayers also exhibit remarkable thermal stability and superior electrical conductivity, vital for high-efficiency electrocatalysis. Furthermore, strain engineering underscores the durability of these materials, maintaining ΔGH* values within ±0.2 eV under extensive tensile strain and emphasizing their practical application potential. Crucially, this work uncovers the critical role of electronic structure adjustments in optimizing the HER performance, aligning with the Sabatier principle, and offering fresh perspectives for designing effective, cost-efficient electrocatalysts. In a word, Janus Zr2COT monolayers emerge as promising candidates, challenging traditional noble metal catalysts and paving the way for the development of sustainable electrocatalytic materials. [ABSTRACT FROM AUTHOR]

The corrosion, parasitic reactions, and aggravated dendrite growth severely restrict development of aqueous Zn metal batteries. Here, we report a novel strategy to break the hydrogen bond network between water molecules and construct the Zn(TFSI)2‐sulfolane‐H2O deep eutectic solvents. This strategy cuts off the transfer of protons/hydroxides and inhibits the activity of H2O, as reflected in a much lower freezing point (<−80 °C), a significantly larger electrochemical stable window (>3 V), and suppressed evaporative water from electrolytes. Stable Zn plating/stripping for over 9600 h was obtained. Based on experimental characterizations and theoretical simulations, it has been proved that sulfolane can effectively regulate solvation shell and simultaneously build the multifunctional Zn‐electrolyte interface. Moreover, the multi‐layer homemade modular cell and 1.32 Ah pouch cell further confirm its prospect for practical application. [ABSTRACT FROM AUTHOR]

Improving the sensitivity of MoS2-based photodetectors by constructing semiconductor heterostructures remains a challenge. To address this issue, the effects of interlayer spacing and vertical external electric fields on the interfacial interactions and electronic properties of Zr2CO2/MoS2 heterostructures were investigated systematically by first-principles calculations. The results indicate that a stable interface with van der Waals interactions can form between Zr2CO2 and MoS2, which complies with the type-II mechanism. By applying a vertical external electric field to the Zr2CO2/MoS2 heterostructure or changing the interlayer spacing between the Zr2CO2 and MoS2 monolayers, both the band gap and heterostructure type at the Zr2CO2/MoS2 interface can be modulated efficiently. It is remarkable that the band alignment of the Zr2CO2/MoS2 heterostructure is more sensitive to the external electric field than to the interlayer spacing. When the electric field is from −0.5 to 0.5 V Å−1, the energy band of the Zr2CO2/MoS2 heterostructure changes from 0.2 to 0.3 eV with a 0.1 V Å−1 increase of electric field. The redistribution of charge density with the external electric field and interlayer coupling is revealed to account for the tunable energy bands. Therefore, the Zr2CO2/MoS2 heterostructures with van der Waals interactions possess great potential to be used in high-performance photodetectors. [ABSTRACT FROM AUTHOR]

An understanding of the high photocatalytic performance reported for MoS2/BiOI nanocomposite is far from satisfactory. Here, the interfacial interaction and electronic properties of a MoS2/BiOI heterostructure were investigated systematically for the first time by first-principle calculations incorporating a semi-empirical dispersion-correction scheme. Our results confirm the reasonable existence of van der Waals interactions and a favorable Z-scheme mechanism, based on the typical interfacial cohesive energy and the energy level lineup at the interface. Analyzing the charge density differences and work functions, the built-in electric field is formed along the direction from MoS2 to BiOI after the interface equilibrium, and facilitates the separation of photoinduced electron–hole pairs in the interface. Additionally, it can be inferred that the incorporation of MoS2 into BiOI increases the carrier mobility and improves light harvesting, in agreement with the previously reported experimental data. Our work provides an insight into the mechanism of the enhanced visible-light photocatalytic activity of a MoS2/BiOI heterostructure, and helps to design other new heterostructure combinations. [ABSTRACT FROM AUTHOR]

Two dimensional (2D) heterojunction based on g‐C3N4 and CuInS2(CIS) nanosheets has been successfully constructed with the assistance of biomolecules L‐cysteine. We demonstrated that a typical p–n junction charges transfer mode of CIS/PCN (protonated g‐C3N4) can be switched to Z‐scheme transfer mode through the integration of Au by weakening the role of built‐in electric field. The morphology of CIS/Au/PCN can be well adjusted through the formation of Au−S covalent bond and the electrostatic adsorption between Au and PCN during the hydrothermal process. Furthermore, the intimate interface contact inside CIS/Au/PCN heterojunction was indeed constructed, which may promote the charges separation and transfer process at the interface as evidenced by ESR spectra and time‐resolved PL spectra. Under visible light illumination, the CIS/Au/PCN exhibited an enhanced CO (19.46 μmol/g) and CH4 (1.18 μmol/g) yield in CO2 reduction, which was about 5.04 times and 2.03 times higher than pure PCN. The composite heterojunction also showed excellent photocatalytic activity for tetracycline degradation with a 87 % degradation efficiency in 1 hour, which was 2.07 times higher than pure PCN. The experimental and theoretical calculation results demonstrated that an all‐solid‐state Z‐scheme heterojunction was formed in the CIS/Au/PCN system, which was different from the typical p–n junction charges transfer mechanism in CIS/PCN. [ABSTRACT FROM AUTHOR]

The surface properties of BiPO4 exert a significant effect on the photocatalytic performance under ultraviolet irradiation, but they have not been well explored, either experimentally or theoretically. Herein, for the first time, we systematically studied the structures and energetics of four low-index stoichiometric surfaces of monazite BiPO4 using density functional theory. A new scheme is proposed to correct the surface energy and compare this with the average surface energy. Both of the two schemes for the surface energies indicate that the order of the surface energies is (100) < (010) < (011) < (001), which is not completely consistent with their surface dangling bond densities. The main reason is incomplete PO4 tetrahedrons, namely, the existence of dangling P–O bonds in the bare (001) plane. However, only dangling Bi–O bonds are found in the other three low-index surfaces. It is obvious that the dangling bond density of the Bi atoms and the intact PO4 tetrahedrons are two crucial factors in the surface stability. Correspondingly, the differences in the planar-averaged electron density and the work function are presented to describe the charge distribution close to the surface. Furthermore, the equilibrium morphology calculated using the Wulff construction suggests that the (001), (010), (011) and (100) facets account for 15%, 33%, 16% and 36%, respectively. The two low-energy (100) and (010) facets dominate in the Wulff shape and make up almost 69% of the total crystal shape area. This work will provide theoretical guidance for the further design of effective BiPO4-based photocatalysts. [ABSTRACT FROM AUTHOR]