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The weak internal electric field over antiferromagnetic materials makes it difficult to facilitate charge migration to the surface, leading to low performance for CO 2 photoreduction. The asymmetry and polarization refinement structure can induce an intensive internal electric field. Herein, n-type NiO is synthesized with highly dispersed erbium atoms doping (Er/NiO 1−x ) via a molten salt method to accelerate charge separation and transfer. The doping of Er atoms can distort the unit cell of NiO to alter the symmetry and enhance the polarization and internal electric field, in favor of efficient separation of charges. In addition, the highly dispersed erbium-doped n-type NiO can largely boost the adsorption and activation of CO 2 , and weaken the energy barrier for CO 2 photoreduction reaction. Benefiting from the unique features, an optimal doping ratio (≈2%) with erbium atoms achieves a remarkable elevation in carrier separation efficiency and excellent CO 2 photoreduction performance with a CO yield of 368 µmol g −1 h −1 in the Ru(byp) 3 2+ /ethanolamine electron-agent generating system, which is 26.3-fold and 3.9-fold relative to traditional NiO and n-type NiO, respectively. The obtained Er/NiO 1−x photocatalyst and the unit cell dipole governing the internal electric field opens a new window for CO 2 photoreduction in antiferromagnetic materials.

Two couples of enantiomerically pure chiral cyano-bridged heterobimetallic chain coordination polymers, [Mn((R,R)-Salcy)Fe(Tp)(CN)(3) x H(2)O x 1/2 CH(3)CN](n) (1), [Mn((S,S)-Salcy)Fe(Tp)(CN)(3) x H(2)O x 1/2 CH(3)CN](n) (2), [Mn((R,R)-Salcy)Fe(bpca)(CN)(3) x H(2)O](n) (3), and [Mn((S,S)-Salcy)Fe(bpca)(CN)(3) x H(2)O](n) (4) [(R,R)-Salcy or (S,S)-Salcy = (R,R)- or (S,S)-N,N'-(1,2-cyclohexanediylethylene)bis(salicylideneiminato) dianion, Tp = tris(pyrazolyl)hydroborate, bpca = bis(2-pyridylcarbonyl)amidate anion], were synthesized using the modified cyanometalate building blocks [Fe(L)(CN)(3)](-) (L = Tp, bpca) and the chiral polydentate Schiff base manganese(III) complex fragments. The circular dichroism measurements showed Cotton effects of the opposite sign at the same wavelength for each pair of enantiomers. Magnetic property studies indicated that complexes 1 and 2 show not only intrachain but also interchain field-induced metamagnetic transitions from an antiferromagnetic to a ferromagnetic state and exhibit an antiferromagnetic long-range ordering with a T(N) of 3.2 K, while enantiomers 3 and 4 are typical antiferromagnetic coupling compounds. Furthermore, complex 3 exhibits a ferroelectric behavior that relates to the polar point group C(2), in which it crystallizes.

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metal catalyst not only has a relatively low metal loading but also greatly improves the utilization efficiency of metal atoms. It can change the adsorption/desorption selectivity of the active components on the catalyst to different molecules, thus affecting the reaction kinetics. [4][5][6] With the development of advanced characterization technologies (synchrotron-radiation X-ray absorption fine structure (XAFS), including X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS); special aberration-corrected transmission electron microscopy (AC-TEM), such as high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), etc.), it has become a reality to elucidate the structure-activity relationship of SACs at the angstroms atomic scale, which also provides an opportunity to link heterogeneous catalysis with homogeneous catalysis. [7,8] In particular, SACs provide a perfect operational platform for the study of molecular level catalytic reaction mechanism. The applications of SACs also become more and more wide, including the versatile heterogeneous catalytic fields (thermocatalysis, electrocatalysis, and photocatalysis) or noncatalytic fields (energy storage battery, electromagnetic wave absorption, and so on).Aerogel is a form of solid matter, one of the least dense solids in the world. The most common aerogel is made of silica; but there are also aerogels made of graphene, metal oxides, polymers, and so on. [9] The lightest silica aerogel is only 3 mg cm −3 , which is 3 times heavier than air, so it is also called "frozen smoke" or "solid smoke." Traditional aerogel material refers to a kind of porous solid material of nanometer or micrometer level formed by the sol-gel method, using certain drying methods (such as freeze drying) to make gas replace liquid phase in gel. [10] Aerogels are highly porous materials (more than 90% porosity), whose internal structure is formed by a network of interconnected basic units (nanosheets, nanofibers, or nanoparticles) separated by open pores. The combination of small basic units, high surface area, and open structure makes aerogels have many unique properties in thermal, mechanical, optical, electrical, and acoustic aspects, which can be used as excellent adsorbents, catalysts, heat insulation materials, and soundThe concept of "single-atom catalysis" is first proposed by Tao Zhang, Jun Li, and Jingyue Liu in 2011. Single-atom catalysts (SACs) have a very high catalytic activity and greatly improved atom utilization ratio. At present, SACs have become frontier materials in the field of catalysis. Aerogels are highly porous materials with extremely low density and extremely high porosity. These pores play a key role in determining their surface reactivity and mechanical stability. The alliance of SACs and aerogels can fully reflect their structural advantages and lead to new enhancement effects. Herein, a general concept of "atomic aerogel materials" (AAMs) (or single-atom aerogels (SAAs)) is proposed to descr...