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Modifying the equilibrium bandgap has proven to be an effective strategy for optimizing photocarrier properties in metal-organic frameworks (MOFs). In this work, we have investigated the nonequilibrium bandgap modification in cobalt porphyrin-based MOF (Co-TCPP MOF) nanofilms through transient absorption spectroscopy. Our results reveal a captivating redshift–blueshift crossover in the nonequilibrium bandgap of Co-TCPP MOFs, with a staggering maximum shifting value of approximately 170 meV, achieved with an excitation fluence of 96 μJ/cm2. This phenomenon sets the stage for further investigations into harnessing nonequilibrium bandgap modification as a powerful tool for tailoring photocarrier properties. Another key facet of our research is the revelation that the bandgap modification effect observed in Co-TCPP MOFs is strongly dependent on the excitation fluence and is absent in disordered porphyrin molecules. This observation suggests a correlation between the bandgap modification and the amplified many-body interactions present within the ordered MOF structure, thus offering valuable insights into the intricate relationship between bandgap modification, excitation fluence, and ordered MOF structures. [ABSTRACT FROM AUTHOR]

This study reports the synthesis of InVO4/α-Fe2O3 heterojunction photocatalysts with different stoichiometric ratios via a two-step hydrothermal synthesis reaction. The prepared photocatalysts were characterized by XRD, SEM, TEM, XPS, and other methods. The prepared composites exhibited good photocatalysis of tetracycline hydrochloride. Among the InVO4/α-Fe2O3 heterojunction photocatalysts with different ratios, the InVO4/0.25α-Fe2O3 photocatalyst showed the highest degradation rate for 20 mg L−1 tetracycline hydrochloride. After three photocatalytic runs, it still exhibited excellent stability and reusability. Meanwhile, this study also found that superoxide radical anion (-O2−), electron (e−), hydroxyl radical (·OH), and photogenerated hole (h+) are the basic active substances in the photocatalytic process. [ABSTRACT FROM AUTHOR]

Porphyrin‐based metal‐organic frameworks (MOFs) have received great attention for solar photochemistry applications. Manipulating the direction of energy (exciton) migration plays an essential role in boosting the light‐harvesting efficiency of porphyrin‐based MOFs. Here, based on the time‐dependent exciton‐exciton annihilation rate, an optical control of directional exciton migration is demonstrated in cobalt‐porphyrin surface‐supported MOF nanofilms (Co‐TCPP SURMOFs). Utilizing photocarrier densities or lattice temperature as the control knob, the dynamic form of exciton migration in Co‐TCPP SURMOFs can be switched between the nearest‐neighbor 1D interaction and the quasi‐isotropic 2D interaction, which is well explained using a diffusion model of exciton‐exciton scattering. This results provide an optical approach to regulating exciton migration in MOFs, which enhances understanding of the excitonic behavior in artificial light harvesters. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) transition metal carbides and/or nitrides (MXene) have emerged as a family of multifunctional materials due to the high electrical conductivity, good stability, abundant and tunable surface functional groups, showing competitive applications in energy storage and conversion. The surface functional groups and their Zeta negative potential properties facilitate the assembly of positively charged organic compounds between the MXene nanosheets to form a stable hybrid, which endow the MXene‐based composite materials better electrochemical performance compared to the individual component. As such, this review exclusively highlights the development of organics/MXene‐based composites and summarizes the various strategies for assembling or fabricating organics/MXene‐based hybrid composites. Applications of these organics/MXene‐based electrode materials in supercapacitors and batteries are also discussed in brief along with analysis of their excellent electrochemical performances and the charge storage mechanisms. Finally, some remaining challenging issues and future opportunities of organics/MXene composites as electrode materials for the high‐power and low‐cost rechargeable batteries or supercapacitors are also discussed. [ABSTRACT FROM AUTHOR]