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Near‐infrared light‐driven photocatalytic CO2 reduction (NIR‐CO2PR) holds tremendous promise for the production of valuable commodity chemicals and fuels. However, designing photocatalysts capable of reducing CO2 with low energy NIR photons remains challenging. Herein, a novel NIR‐driven photocatalyst comprising an anionic Ru complex intercalated between NiAl‐layered double hydroxide nanosheets (NiAl‐Ru‐LDH) is shown to deliver efficient CO2 photoreduction (0.887 μmol h−1) with CO selectivity of 84.81 % under 1200 nm illumination and excellent stability over 50 testing cycles. This remarkable performance results from the intercalated Ru complex lowering the LDH band gap (0.98 eV) via a compression‐related charge redistribution phenomenon. Furthermore, transient absorption spectroscopy data verified light‐induced electron transfer from the Ru complex towards the LDH sheets, increasing the availability of electrons to drive CO2PR. The presence of hydroxyl defects in the LDH sheets promotes the adsorption of CO2 molecules and lowers the energy barriers for NIR‐CO2PR to CO. To our knowledge, this is one of the first reports of NIR‐CO2PR at wavelengths up to 1200 nm in LDH‐based photocatalyst systems. [ABSTRACT FROM AUTHOR]

Intercalation of the [ Ru( dpds) 3] 4 complex into a layered double hydroxide structure is reported byLihong Liu, Wenkai Zhang, Yufei Zhao et al. in their Research Article ( e202407638). Under infrared light irradiation at 1200 nm, the obtained intercalation structure exhibits remarkable photocatalytic performance in converting CO2 to CO with excellent stability, demonstrating for the first time CO2 reduction at such long wavelengths. [Extracted from the article]

• We have obtained the mixed metal oxides as the outstanding heavy metal mineraliser for Pb2+ irons. • The mineralization mechanisms towards different concentrations of Pb2+ were fully demonstrated by XAFS and DFT calculation. • The mineralized Pb2+ could be recycled by electrolysis to obtain the metallic lead. Lead (Pb) as one of the most widespread toxic heavy metals in both water distribution systems and in surface water, it still remains a challenge to quickly and completely remove/recycle Pb ions from these systems. Herein, the obtained Mg 2 Fe-mixed metal oxides (Mg 2 Fe-MMO) through calcination of Mg 2 Fe-Cl-layered double hydroxide (Mg 2 Fe-Cl-LDH) showed extremely high mineralized capacity for Pb ions with removal figures of 2406 mg/g. This performance is superior to most reported materials, and can rapidly purify Pb2+ at 1 ppm to safe levels (12 ppb). X-ray absorption fine structure (XAFS) studies revealed a transformation from MgFe-MMO to defective Mg 2 Fe-CO 3 -LDH with the Pb ions sequestering OH− from Mg 2 Fe-CO 3 -LDH to form a solid precipitate. Moreover, the mineralized products could be recycled by electrolysis to obtain metallic lead, providing a new opportunity for pollution remediation and the recovery of metal lead. This work provides a new route for Pb ions removal from wastewater and the potential for utilization of the recycled Pb resource. [ABSTRACT FROM AUTHOR]

[Display omitted] • The CaAl-LDH exhibited excellent removal efficiency with the removal capacity of Cu2+, Zn2+, Ni2+, and Co2+ exceeding 400 mg/g. • For actual electroplating wastewater, CaAl-LDH showed outperforming mineralization performance to meet the WHO drinking water standard. • The mineralisation mechanism in LDH was confirmed based on X-ray absorption fine structure (EXAFS) and Density functional theory (DFT) calculations. • The Ni2+ mineralized products can efficiently convert CO 2 into fuel (CH 4 , CO) through photocatalysis with excellent selectivity and stability. From an environmental and resource management perspective, it is preferable to recover and reuse heavy metal ions found in electroplating wastewater. The discharge of electroplating wastewater has caused serious environmental pollution and resource waste. Ca-based layered double hydroxides (LDHs) stabilizers are designed, which show a rapid, effective, and adequate capacity exceeding 400 mg/g against solutions of Cu2+, Zn2+, Co2+, and Ni2+ ions through an isomorphous substitution mechanism. The needs of plant development were met by the use of CaAl-LDH in soil remediation. While Cu resources can be recovered from the CuAl-LDH products by electrolysis, the final mineralization products from Ni2+ and Zn2+ ions showed exceptional performance in visible-light-induced photocatalytic reduction of CO 2 with excellent selectivity (98.7% toward CO and CH 4) and the removal of arsenite ions (99.97%). The results of this investigation revealed a feasible new approach to the removal, recycling, and reutilization of heavy metal ions. [ABSTRACT FROM AUTHOR]

[Display omitted] • The atomic economical synthesis of CaCr-LDH and the rapid purification of wastewater containing high concentration of Cr3+ are realized by super-stable mineralization. • Through multistage super-stable mineralization, using CaCr-LDH to treat multiple divalent heavy metal ions can reduce costs by about 50% and sludge by about 10%. • The product showed excellent performance in photocatalytic CO 2 reduction and precious metal (Au) recovery from printed circuit board leaching wastewater. The treatment and recycling of heavy metal pollutants are vital for the restoration of the ecological environment and the recovery and reuse of resources. Herein, we report an atomic-economic method to synthesize a novel CaCr-layered double hydroxide (LDH) by extracting toxic Cr3+ (more than 1000 mg/L) from industrial wastewater, by which the wastewater can be purified to discharge standards. The obtained CaCr-LDH can be reused for the super-stable mineralization of multiple heavy metal ions with a high capacity, and the removal capacities of Ni, Co, Cu and Zn ions are 306.7 mg/g, 578.0 mg/g, 657.9 mg/g, and 352.1 mg/g, respectively. Furthermore, CaCr-LDH has the advantages of a large treatment range, anti-interference, alkali corrosion resistance, low cost, and less sludge. In the above mineralization process, CaCr-LDH converts to MCaCr-LDH (M = Co, Ni, Cu, and Zn) through an isomorphous substitution process. The obtained NiCaCr-LDH products show excellent performance in photocatalytic CO 2 reduction with a high CH 4 selectivity of 34.8% under visible light. The MCaCr-LDH products can selectively adsorb gold ions with approximately 90% adsorption efficiency and reduce them with approximately 80% reduction efficiency from printed circuit board leaching wastewater, offering promising functionalities for improving environmental pollution, resource waste, and energy crises. [ABSTRACT FROM AUTHOR]

• The multi-metallic LDHs provide exciting electronic property than traditional binary LDHs. • The transformation from binary LDH to LMMH (layered multi-metallic hydroxides) is accompanied by changes in electronic or morphological structure. • The prepared LDHs exhibit enhanced photo/electrocatalytic performance. The development of efficient photo/electrocatalysis using sustainable renewable resources to prepare high value-added products is now a major goal to achieve new environmentally friendly technologies. However, existing solutions still offer unsatisfied catalytic efficiency and low energy utilization. Therefore, it is paramount to develop new strategies to control the morphology and structure of functional materials to improve their photo/electrocatalytic activity. Layered double hydroxides (LDHs), as a kind of two-dimensional (2D) materials, have been largely explored in photo/electrocatalytic reactions due to their extensive tenability of elemental composition and interlayered anions. Furthermore, the intrinsic feature of atomic dispersion has been utilized to introduce more active sites to further improve the reaction performance. Herein, we review strategies that have been developed for introducing more active sites into or onto the LDH layer for the construction of multi-metallic LDHs based photo/electrocatalytic material. The accompanied structure and electronic changes that are pivotal for modulation for catalytic activity are proposed, such as, improving carrier transportation, and optimizing molecular activation energy. We review the catalytic performance of multi-metallic LDHs for photo/electrocatalytic water splitting, CO 2 photoreduction, CO hydrogenation, heavy metal mineralization/reutilization and beyond. We highlight future challenges and opportunities to design multi-metallic LDHs to address future photo/electrocatalysis research challenges. [ABSTRACT FROM AUTHOR]