The development of efficient and low energyconsumption catalysts for CO 2 conversion is desired, yet remains ag reat challenge.H erein, ac lass of novel hollow porous carbons (HPC), featuring well dispersed dopants of nitrogen and single Zn atoms,h ave been fabricated, based on the templated growth of ah ollow metal-organic framework precursor,f ollowed by pyrolysis.T he optimizedH PC-800 achieves efficient catalytic CO 2 cycloaddition with epoxides, under light irradiation, at ambient temperature,b yt aking advantage of an ultrahigh loading of (11.3 wt %) single-atom Zn and uniform Na ctive sites,h igh-efficiency photothermal conversion as well as the hierarchicalpores in the carbon shell. As far as we know,this is the first report on the integration of the photothermal effect of carbon-based materials with single metal atoms for catalytic CO 2 fixation.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.

Two three-dimensional (3D) coordination networks, [Co 3 (1,4-BDC)3(L 1 )] N (L 1 ¼ N,N 0 -bis(3-pyridinyl)-1,4-benzenedicarboxamide; 1,4-H 2 BDC ¼ 1,4-benzenedicarboxylic acid), 1, and [K 2 Co 3 (L 2 ) 4 ] N (H 2 L 2 ¼ 5-acetamidoisophthalic acid), 2, have been synthesized by hydrothermal reactions and characterized by single crystal X-ray crystallography. Complex 1 consists of linear trinuclear Co(II) centers, which are linked by the 1,4-BDC À and L 1 ligands to form a rare (1 + 3) self-catenated 3D net with the new (3 6 ,4 10 ,5 11 ,6) topology, and complex 2 reveals a 3p-3d heterometallic coordination network based on linear trinuclear Co(II) and dinuclear K(I) centers bridged by the m 6 -L 2 ligands, forming a 4,4,8-connected trinodal net with the new (4 14 $6 10 $8 4 )(4 2 $6 4 )(4 4 $6 2 ) topology. The linear trinuclear Co(II) centers in 1 adopt the square pyramidal-octahedral-square pyramidal geometries, whereas those in 2 are tetrahedral-octahedral-tetrahedral. Both of the complexes exhibit paramagnetism that is consistent with the Curie-Weiss law between 60 and 300 K. The effective magnetic moments (hm eff i) of both complexes are larger than the estimated value of 6.71 m B /f.u., revealing the spin-orbit couplings that are invoked by the different distorted geometries of the linear trinuclear Co(II) centers. The dinuclear K(I) centers in 2 weaken the magnetic coupling, and reduce the antiferromagnetic ordering at 6 K.

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The effect of the size of TbMn2O5 on their magnetoelectric properties is studied using a field emission transmission electron microscope, ac magnetic susceptibility, relative dielectric constant, specific heat capacity, and x-ray diffraction at various temperatures. A bulk sample and nanorods with two axial lengths, ⟨LC⟩, are investigated. Nanorods with ⟨LC⟩ of 216 nm and 64 nm crystallize with orthorhombic Pbam symmetry as the bulk material. The axial direction of the two sizes of nanorod is parallel to the c axis of the crystal. No particular radial direction is observed. The critical size for the magnetic ordering of TbMn2O5 is found to be between ⟨LC⟩ = 64 nm and 216 nm. Experiments on specific heat capacity verified these results. No similar phenomenon concerning the ferroelectric property is observed. At T = 30 K and 35 K, the ⟨LC⟩ = 216 nm sample yields a charge-ordering-like x-ray diffraction peak, which may be associated with the magnetically induced charge ordering superlattice.

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