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Effective combination of the photosensitive and photoactive units in metal–organic frameworks (MOFs) is vital to achieving efficient solar energy utilization for superior photocatalytic efficiency. In this study, we successfully organize photosensitive metalloporphyrin ligands and photoactive building units (Ti-oxo clusters) uniformly at a molecular level within a heterobimetallic metal–organic framework (MOF) nanostructure, denoted as TMF-(X), where X represents Zn, Co, or Cu. The well-accessible Ti sites possess a close proximity to the metalized porphyrin, which is favorable for the electron-transfer kinetics to the photocatalytic center for the redox reaction. Furthermore, the metal ions at the porphyrin center are able to induce electron redistribution, more negative conduction band potential, and enhanced light absorption, which boosts the photocatalytic H2 evolution performance. Notably, the resulting heterobimetallic MOF nanostructures exhibited remarkably enhanced photocatalytic H2 evolution performance, especially for the nano TMF-(Zn) with a maximum H2 evolution rate of 3.24 mmol g–1 h–1 under visible light irradiation, which is much higher than that of TMF (1.40 mmol g–1 h–1). Our work opens up a way for highly efficient MOF-based photocatalysts for H2 evolution and beyond. [ABSTRACT FROM AUTHOR]

Herein, via first‐principle calculations and theoretical analysis, a new Dirac semimetal carbon system called C32, which is composed of pentagonal, hexagonal, heptagonal, and octagonal carbon rings is systematically investigated. The stability of C32 is verified by calculating the phonon dispersion, elastic constants, etc., and an appropriate pathway for experimental synthesis is proposed. Besides, it is discovered that the system holds the quadruple rotation and inversion symmetry, resulting in the emergence of eight twisted Dirac cones (D1 and D2) with a highly anisotropic Fermi velocity from 3.83 × 105 to 8.96 × 105 m s−1 along different k directions. To substantiate the semimetallic nature of C32, its nontrivial topological properties are confirmed through the presence of topologically protected edge states, and the nonzero ℤ2 topological invariant. More importantly, by introducing biaxial strain, it is uncovered that Dirac cones can gradually evolve into a nodal line, and the perfect nodal line can be obtained when the biaxial strain is 13.3%. Furthermore, by constructing the tight‐binding model, the appearance of the Dirac cone is perfectly repeated and its evolution into the nodal line under biaxial strain is explained. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have recently gained attention as a highly promising category of photocatalytic materials, showing great potential in the degradation of organic dyes such as Rhodamine B (RhB). Nonetheless, the mono-metal MOF materials in this application are often constrained by their limited light absorption capabilities and their propensity for recombination with carriers. The combination of different metal-based MOFs to form heterogeneous reactors could present a promising approach for the removal of dyes from water. In this work, a new CAU-17/MIL-100(Fe) Z-scheme heterojunction photocatalyst composed of two MOFs with the same ligands is reported to realize the efficient degradation of dyes in water. The combination of the two MOFs results in a significant enhancement of the surface open sites, optical responsivity range, and charge-separating efficiency through synergistic effects. In addition, the capture experiments conducted on the photocatalytic process have verified that ∙O2− and h+ are the primary active species. Consequently, CAU-17/MIL-100(Fe) exhibited excellent photocatalytic activity and stability. The degradation rate of the optimal CAU-17/MIL-100(Fe) photocatalyst was 34.55 times that of CAU-17 and 3.60 times that of MIL-100(Fe). Our work provides a new strategy for exploring the visible-light degradation of RhB in bimetallic MOF composites. [ABSTRACT FROM AUTHOR]

Due to their large theoretical capacity, transition metal sulfides are regarded as ideal anode materials for lithium‐ion batteries (LIBs). However, a number of technical challenges and scientific issues, such as low utilization of active materials and large volumetric expansion, must be addressed before it can be used in practice. Herein, CoS2‐embedded N‐doped carbon polyhedrons are constructed successfully and employed as an efficient anode of LIB. After 200 cycles at a current density of 0.2 Ag−1, the optimal CoS2@NC‐400 demonstrates a high reversible capacity of 866.2 mAhg−1, and after 500 cycles at a current density of 0.5 Ag−1, there is no discernible capacity fading. The excellent electrochemical performance of CoS2@NC‐400 can be attributed to that graphitic N‐doped porous carbon provides a highly conductive framework, which facilitates electron transports and lessens the volume expansion of electrode during charging and discharging. Furthermore, the pyrrolic N‐doped carbon in the CoS2@NC‐400 composite allows for a lower diffusion barrier for Li‐ions in the electrode. [ABSTRACT FROM AUTHOR]

It is highly desirable but challenging to optimize the electronic structure of an active site to realize moderate active site-H ads bond energies for boosting photocatalytic H 2 evolution. Herein, an interfacial engineering strategy is developed to simultaneously concentrate hydrogen species and accelerate the combination of an H ads intermediate to generate free H 2 by constructing W-WC-W 2 C (WCC) cocatalysts. Systematic investigations reveal that hybridizing with W 2 C creates electron-rich W active sites and effectively induces the downshift of the d-band center of W in WC. Consequently, the strong W-H ads bonds on the surface of WC are weakened, thus promoting the desorption of H ads to rapidly produce free H 2 . The optimized 40-WCC/CdS photocatalyst exhibits a high hydrogen evolution rate of 63.6 mmol g -1 h -1 under visible light (≥420 nm) with an apparent quantum efficiency of 39.5% at 425 nm monochromatic light, which is about 40-fold of the pristine CdS. This work offers insights into the design of cocatalyst for high-efficiency photocatalytic H 2 production.