Establishing high performance ultraviolet (UV) nonlinear optical (NLO) selenite crystals with well‐balanced properties is very challenging attributable to their strong absorption for UV light. Here a rare‐earth selenite, Sc(HSeO3)3, with excellent UV NLO properties is introduced. Sc(HSeO3)3 crystallizing in the polar NCS space group, Cc, features a 3D archetiture built up by interconnected ScO6 octahedra and HSeO3 groups. The crystal exhibits remarkably well‐balanced UV‐NLO functionality, namely, the shortest absorption edge (214 nm) among NLO‐active selenites, wide bandgap (5.28 eV), large phase‐matchable SHG response (5 × KDP), and sufficiently large birefringence (cal. 0.105 @1064 nm). Detailed DFT calculations have been performed to elucidate the structure–property relationships. This work provides a new example of discovering novel UV NLO selenite materials.

A metal–organic framework (MOF) was synthesized using 4,4′‐stilbenedicarboxylic acid (H2SDA) in dimethylformamide (DMF). Carbon‐coated Co (C@Co) catalysts were prepared by the direct calcination of Co3(SDA)3(DMF)2 MOF crystals at various temperatures. The highest surface area of the C@Co catalyst is obtained at 600 °C which can further be increased by the ball mill operation. The X‐ray photon spectroscopy and X‐ray diffraction analysis proved the formation of metallic Co in the carbon matrix at temperatures over 500 °C, while Co3O4 formation was observed at 500 °C. Furthermore, the graphitic properties of the Co particles were analyzed by Raman spectroscopy. The durability of the carbon‐coated Co catalysts derived from MOFs (C@Co catalysts) was analyzed by the cycle test (charge/discharge at 20 mA/cm2 per 2 h) and was retained over 350 h. These catalysts showed remarkable stability for both ORR (oxygen reduction reaction) and OER (oxygen evolution reaction), comparable to that of Co3O4 and Co metal powder in alkaline solution.

New enantiomorphic Pb-based metal-organic coordination polymers, i.e., [Pb((R,R)-TBA)(H2O)]·1.7H2O (R1) and [Pb((S,S)-TBA)(H2O)]·1.7H2O (S1) (TBA = 1,3,5-triazin-2(1H)-one-4,6-bis(alanyl)), have been successfully synthesized through solvothermal reactions with the aid of carefully designed corresponding chiral...