The uncontrolled dendrite growth and volume change of Li metal during cycling lead to a short cycle life and safety concerns for Li-metal batteries, which hinders their practical application. Herein, we report the facile and energy-saving production of a three-dimensional (3D) CuZn matrix decorated with in-situ formed ZnO nano seeds (ZnO NS@3D CuZn) in pores and tunnels, which can serve as an anode current collector for dendrite-free Li-metal batteries. The 3D porous framework reduced the anode current density and accommodated Li volume change during the charge/discharge process. More importantly, the lithiophilic ZnO nano seeds induced fast Li deposition into the pores and tunnels of the 3D structure to effectively confine the deposited Li. As a positive effect, the volume change and Li dendrite growth during cycling are greatly suppressed. The half-cell with the ZnO NS@3D CuZn current collector exhibited a Coulombic efficiency (CE) of above 98% for over 320 and 240 cycles at 0.5 and 1 mA·cm⁻², respectively. The Li@ZnO NS@3D CuZn symmetric cell achieves a lifespan of over 1500 h. Moreover, the Li@ZnO NS@3D CuZn||LiFePO₄ full cell achieves a superb average CE of 99.4% and a long life of 600 cycles before the capacity retention rate decays to 90%.

Porphyrinoid metal-organic frameworks (MOFs) with dual effective uranium uptake sites were synthesized through combined in-situ and post-synthetic method. The MOF10@5 demonstrates the uptake amount of uranium reaches 1476 mg/g under visible-light irradiation. The PN-MOF10@5 with dual uranyl uptake sites yields the amount of extracting uranyl of 1590 mg/g under visible-light irradiation. The density functional theory (DFT) calculations reveal strong interaction between uranyl and dual uranyl effective active sites. These MOFs demonstrate a powerful synthesis strategy for uranium extraction materials with dual effective active sites.

Aqueous rechargeable batteries (ARBs) are generally safer than non-aqueous analogues, they are also less-expensive, and more friendly to the environment. However, the inherent disadvantage of the narrow electrochemical window of H₂O seriously restricts the energy density and output voltage of ARBs, especially aqueous rechargeable Fe-based batteries. Herein, we introduce a new battery system: the anode contains C@Fe/Fe₂O₃ composite, which is interfaced with an alkaline electrolyte; the cathode contains LiMn₂O₄ in contact with a neutral electrolyte. A Li⁺-conducting membrane is carefully selected to decouple the electrode–electrolyte, which effectively widens the electrochemical window to above 2.65 V, thereby enables an aqueous rechargeable iron battery. Its average output voltage is 1.83 V and its energy density is 235.3 Wh/kg at 549 W/kg. In this work, we propose the energy storage mechanism with the aid of density functional theory (DFT). The calculated reduction potential of the anode agrees with the experimental value. Furthermore, this battery system demonstrates long cycle lifespan of approximately 2500 cycles at 2 A/g, corresponding to a capacity retention of 82.1%. These results are very far superior than those of mainstream aqueous rechargeable Fe-based batteries, which guarantee future investigation for storing electricity energy.

Metal-organic frameworks (MOFs) are favored in the fields of adsorption, separation, catalysis, electrochemistry, and magnetism due to their advantages of large specific surface area, high porosity, controllable pore size adjustment, and dispersion of metal active sites. The application of MOFs involves multiple fields, which requires that MOFs have good water stability, as gaseous and liquid water inevitably exist in industrial processes. In this paper, the research status of the stability of MOFs in aqueous solutions was reviewed in recent years, including the design and synthesis, the influencing factors, and the applications of MOFs in water stability.

Cu-based materials are seldom reported as oxygen evolution reaction (OER) electrocatalysts due to their inherent electron orbital configuration, which makes them difficult to adsorb oxygen-intermediates during OER. Reasonably engineering the hierarchical architectures and the electronic structures can improve the performance of Cu-based OER catalysts, such as constructing multilevel morphology, inducing the porous materials, improving the Cu valence, building heterostructures, doping heteroatoms, etc. In this work, copper-1,3,5-benzenetricarboxylate (HKUST-1) octahedra in-situ grow on the Cu nanorod (NR)-supported N-doped carbon microplates, meanwhile an active layer of Cu(OH)₂ forms on the surface of the original conductive Cu NRs. The octahedral HKUST-1, serving as a spacer between the microplates, greatly improves the porosity and increases the available active sites, facilitating the mass transport and electron transfer, thus resulting in greatly enhanced OER performance.

In recent years, since water pollution has aroused great public concern, various carbon materials have already been widely applied for water treatment. In this respect, tremendous effort has been made to provide different synthesis methods of carbon materials. Among all carbon materials, metal-organic framework (MOF) derived carbon has always been favored as it possesses several appealing merits such as high specific surface area, large pore volume, and outstanding chemical stability. This review presents the latest development of MOFs as templates and precursors for the fabrication of various carbon materials, including porous carbon, nanocarbon, and graphene, which are pyrolyzed at different temperatures. The article also emphasizes on their future trends and perspectives on the application of water treatment.

With the increasing demand for fuel causing serious environmental pollution, it is urgent to develop new and environmentally friendly energy conversion devices. These energy conversion devices, however, require good, inexpensive materials for electrodes and so on. The multifunctional properties of porphyrins enable framework materials (e.g., metal-organic frameworks and covalent organic frameworks) to be applied in energy conversion devices due to their simple synthesis, high chemical stability, abundant metallic active sites, adjustable crystalline structure and high specific surface area. Herein, the types of porphyrin structural blocks are briefly reviewed. They can be used as organic ligands or directly assembled with framework materials to generate high-performance electro-/photo-catalysts. These types of catalysts applied in electro-/photo-catalytic water splitting, electro-/photo-catalytic carbon dioxide reduction, and electrocatalytic oxygen reduction are also summarized and introduced. At the end of the article, we present the challenges of porphyrin-based framework materials in the above application and corresponding solutions. We expect porphyrin-based framework materials to flourish energy conversion in the coming years.

The ultrahigh specific energy density and low cost of lithium-sulfur batteries are suitable for the next generation of energy storage. However, the shuttle issue and sluggish conversion kinetics of polysulfides remain unsolved. Confining metal nanoclusters with strong polarity in conductive porous carbon is an effective strategy for tackling such knotty issues. Herein, we design and synthesize hollow cubic carbon embedded with highly dispersed cobalt nanoclusters as an effective sulfur reservoir for lithium sulfur batteries. The large cavity structure and well-dispersed cobalt nanoclusters, with uniform sizes near 11 nm, enable the hosting structure to hold the high sulfur loading, 70% capacity retention after 500 cycles at 2 C with a high sulfur loading of 6.5 mg·cm⁻², effective stress release, accelerated polysulfide conversion, superior rate performance, strong physical confinement and chemical absorption capability. Further density functional theoretical calculations demonstrate that the well-dispersed cobalt nanoclusters in the hosting structure play a critical electrocatalytic role in boosting the capability of absorbing and converting polysulfides.

The urea oxidation reaction has attracted increasing attention. Here, porous rod-like Ni₂P/Ni assemblies, which consist of numerous nanoparticle subunits with matching interfaces at the nanoscale have been synthesized via a simple phosphating approach. Density functional theory calculations and density of states indicate that porous rod-like Ni₂P/Ni assemblies can significantly enhance the activity of chemical bonds and the conductivity compared with NiO/Ni toward the urea oxidation reaction. The optimal catalyst of Ni₂P/Ni can deliver a low overpotential of 50 mV at 10 mA·cm^-2 and Tafel slope of 87.6 mV·dec^-1 in urea oxidation reaction. Moreover, the constructed electrolytic cell exhibits a current density of 10 mA·cm^-2 at a cell voltage of 1.47 V and an outstanding durability in the two-electrode system. This work has provided a new possibility to fabricate metal phosphides-metal assemblies with advanced performance.