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Structural variants of high‐nuclearity clusters are extremely important for their modular assembly study and functional expansion, yet the synthesis of such giant structural variants remains a great challenge. Herein, we prepared a lantern‐type giant polymolybdate cluster (L‐Mo132) containing equal metal nuclearity with the famous Keplerate type Mo132 (K‐Mo132). The skeleton of L‐Mo132 features a rare truncated rhombic triacontrahedron, which is totally different with the truncated icosahedral K‐Mo132. To the best of our knowledge, this is the first time to observe such structural variants in high‐nuclearity cluster built up of more than 100 metal atoms. Scanning transmission electron microscopy reveals that L‐Mo132 has good stability. More importantly, because the pentagonal [Mo6O27]n− building blocks in L‐Mo132 are concave instead of convex in the outer face, it contains multiple terminal coordinated water molecules on its outer surface, which make it expose more active metal sites to display superior phenol oxidation performance, which is more higher than that of K‐Mo132 coordinated in M=O bonds on the outer surface. [ABSTRACT FROM AUTHOR]

Hybrid CO2 electroreduction (HCER) is recognized as an important strategy to improve the total value of redox products and energy conversion efficiency. In this work, a coordination catalyst model system (Ni8‐TET with active oxidation sites, Ni‐TPP with active reduction sites and PCN‐601 with redox‐active sites) for HCER was established for the first time. Especially, PCN‐601 can complete both anodic methanol oxidation and cathodic CO2 reduction with FEHCOOH and FECO over 90 %. The performance can be further improved with light irradiation (FE nearly 100 %). DFT calculations reveal that the transfer of electrons from NiII8 clusters to metalloporphyrins under electric fields results in the raised oxidizability of Ni8 clusters and the raised reducibility of metalloporphyrin, which then improves the electrocatalytic performance. This work serves as a well‐defined model system and puts forward a new design idea for establishing efficient catalysts for hybrid CO2 electroreduction. [ABSTRACT FROM AUTHOR]

As hot topics in the chemical conversion of CO2, the photo‐/electrocatalytic reduction of CO2 and use of CO2 as a supporter for energy storage have shown great potential for the utilization of CO2. However, many obstacles still exist on the road to realizing highly efficient chemical CO2 conversion, such as inefficient uptake/activation of CO2 and mass transport in catalysts. Covalent organic frameworks (COFs), as a kind of porous material, have been widely explored as catalysts for the chemical conversion of CO2 owing to their unique features. In particular, COF‐based functional materials containing diverse active sites (such as single metal sites, metal nanoparticles, and metal oxides) offer great potential for realizing CO2 conversion and energy storage. This Minireview discusses recent breakthroughs in the basic knowledge, mechanisms, and pathways of chemical CO2 conversion strategies that use COF‐based functional catalysts. In addition, the challenges and prospects of COF‐based functional catalysts for the efficient utilization of CO2 are also introduced. [ABSTRACT FROM AUTHOR]

Purposefully designing the well‐defined catalysts for the selective electroreduction of CO2 to C2H4 is an extremely important but challenging work. In this work, three crystalline trinuclear copper clusters (Cu3‐X, X=Cl−, Br−, NO3−) have been designed, containing three active Cu sites with the identical coordination environment and appropriate spatial distance, delivering high selectivity for the electrocatalytic reduction of CO2 to C2H4. The highest faradaic efficiency of Cu3‐X for CO2‐to‐C2H4 conversion can be adjusted from 31.90 % to 55.01 % by simply replacing the counter anions (NO3−, Cl−, Br−). The DFT calculation results verify that Cu3‐X can facilitate the C−C coupling of identical *CHO intermediates, subsequently forming molecular symmetrical C2H4 product. This work provides an important molecular model system and a new design perspective for electroreduction of CO2 to C2 products with symmetrical molecular structure. [ABSTRACT FROM AUTHOR]

In the electrochemical CO2 reduction reaction (CO2RR), it is challenging to develop a stable, well‐defined catalyst model system that is able to examine the influence of the synergistic effect between adjacent catalytic active sites on the selective generation of C1 or C2 products. We have designed and synthesized a stable crystalline single‐chain catalyst model system for electrochemical CO2RR, which involves four homomorphic one‐dimensional chain‐like compounds (Cu‐PzH, Cu‐PzCl, Cu‐PzBr, and Cu‐PzI). The main structural difference of these four chains is the substituents of halogen atoms with different electronegativity on the Pz ligands. Consequently, different synergistic effects between bi‐copper centers lead to changes in the faradic efficiency (FECH4 :FEC2H4). This work provides a simple and stable crystalline single‐chain model system for systematically studying the influence of coordination microenvironment on catalytically active centers in the CO2RR. [ABSTRACT FROM AUTHOR]

In this work, we rationally designed a series of crystalline and stable dioxin‐linked metallophthalocyanine covalent organic frameworks (COFs; MPc‐TFPN COF, M=Ni, Co, Zn) under the guidance of reticular chemistry. As a novel single‐site catalysts (SSCs), NiPc/CoPc‐TFPN COF exhibited outstanding activity and selectivity for electrocatalytic CO2 reduction (ECR; Faradaic efficiency of CO (FECO)=99.8(±1.24) %/ 96.1(±1.25) % for NiPc/CoPc‐TFPN COF). More importantly, when coupled with light, the FECO and current density (jCO) were further improved across the applied potential range (−0.6 to −1.2 V vs. RHE) compared to the dark environment for NiPc‐TFPN COF (jCO increased from 14.1 to 17.5 A g−1 at −0.9 V; FECO reached up to ca. 100 % at −0.8 to −0.9 V). Furthermore, an in‐depth mechanism study was established by density functional theory (DFT) simulation and experimental characterization. For the first time, this work explored the application of COFs as photo‐coupled electrocatalysts to improve ECR efficiency, which showed the potential of using light‐sensitive COFs in the field of electrocatalysis. [ABSTRACT FROM AUTHOR]

Solar energy‐driven conversion of CO2 into fuels with H2O as a sacrificial agent is a challenging research field in photosynthesis. Herein, a series of crystalline porphyrin‐tetrathiafulvalene covalent organic frameworks (COFs) are synthesized and used as photocatalysts for reducing CO2 with H2O, in the absence of additional photosensitizer, sacrificial agents, and noble metal co‐catalysts. The effective photogenerated electrons transfer from tetrathiafulvalene to porphyrin by covalent bonding, resulting in the separated electrons and holes, respectively, for CO2 reduction and H2O oxidation. By adjusting the band structures of TTCOFs, TTCOF‐Zn achieved the highest photocatalytic CO production of 12.33 μmol with circa 100 % selectivity, along with H2O oxidation to O2. Furthermore, DFT calculations combined with a crystal structure model confirmed the structure–function relationship. Our work provides a new sight for designing more efficient artificial crystalline photocatalysts. [ABSTRACT FROM AUTHOR]

Visible‐light driven photoconversion of CO2 into energy carriers is highly important to the natural carbon balance and sustainable development. Demonstrated here is the adenine‐dependent CO2 photoreduction performance in green biomimetic metal–organic frameworks. Photocatalytic results indicate that AD‐MOF‐2 exhibited a very high HCOOH production rate of 443.2 μmol g−1 h−1 in pure aqueous solution, and is more than two times higher than that of AD‐MOF‐1 (179.0 μmol g−1h−1) in acetonitrile solution. Significantly, experimental and theoretical evidence reveal that the CO2 photoreduction reaction mainly takes place at the aromatic nitrogen atom of adenine molecules through a unique o‐amino‐assisted activation rather than at the metal center. This work not only serves as an important case study for the development of green biomimetic photocatalysts used for artificial photosynthesis, but also proposes a new catalytic strategy for efficient CO2 photoconversion. [ABSTRACT FROM AUTHOR]

Abstract: Crystalline and porous covalent organic frameworks (COFs) and metal‐organic frameworks (MOFs) materials have attracted enormous attention in the field of photocatalytic H2 evolution due to their long‐range order structures, large surface areas, outstanding visible light absorbance, and tunable band gaps. In this work, we successfully integrated two‐dimensional (2D) COF with stable MOF. By covalently anchoring NH2‐UiO‐66 onto the surface of TpPa‐1‐COF, a new type of MOF/COF hybrid materials with high surface area, porous framework, and high crystallinity was synthesized. The resulting hierarchical porous hybrid materials show efficient photocatalytic H2 evolution under visible light irradiation. Especially, NH2‐UiO‐66/TpPa‐1‐COF (4:6) exhibits the maximum photocatalytic H2 evolution rate of 23.41 mmol g−1 h−1 (with the TOF of 402.36 h−1), which is approximately 20 times higher than that of the parent TpPa‐1‐COF and the best performance photocatalyst for H2 evolution among various MOF‐ and COF‐based photocatalysts. [ABSTRACT FROM AUTHOR]