Electrocatalytic technology opens a new path to solve the existing problems in fossil fuel consumption and environmental pollution as well as efficient energy use. Metal-organic frameworks (MOFs), a class of...

We report a unique vinyl coordination polymer (CP), [Zn(4‐Fb)2(tkpvb)]n (1, 4‐HFb=4‐fluorobenzoic acid, tkpvb=1,2,4,5‐tetrakis(4‐pyridylvinyl)benzene) that undergoes a rare photopolymerization reaction to form a two‐dimensional CP integrated with a one‐dimensional linear organic polymer. Upon light irradiation at different wavelengths, 1 exhibits an unprecedented phenomenon of photoinduced nonlinear lattice expansion. 1 can be uniformly dispersed in polyvinyl alcohol (PVA) to form the composite film of 1‐PVA. When this film is exposed to UV light, internal minute stresses within crystallites are released by lattice expansion, resulting in a variety of photopolymerization‐driven macroscopic mechanical motions. The findings provide new insights into the conversion of small lattice expansions of CPs into macroscopic mechanical motions based on photopolymerization reactions, which can promote the development of CPs‐based smart photoactuators in the burgeoning field of microrobotics.

Changing the chemical composition and generating heterogeneous structures have a synergistic effect on the third‐order nonlinear optical (NLO) properties of metal–organic frameworks (MOFs) materials. In this work, it is demonstrated that the transformations from a parent‐MOF [Zn4(dcpp)2(DMF)3(H2O)2]n (1, dcpp = 3,4‐bis(4‐carboxyphenyl)phthalate) into two child‐MOFs, [Cu4(dcpp)2(DMF)3(H2O)2]n (2) or [Zn2.5Co1.5(dcpp)2(DMF)3(H2O)2]n (3), via central metal exchange can regulate the third‐order NLO properties of the parent‐MOF, especially its third‐order NLO absorption signal can change from the reverse saturable absorption (RSA) to the saturable absorption (SA) when Cu2+ are introduced. Heterogeneous 1@CeO2 materials are further engineered by depositing CeO2 nanospheres onto the whole surface of 1, and are surprisingly still able to be exchanged into 2@CeO2 or 3@CeO2. Analyses on these MOFs@CeO2 indicate that the interfacial interaction between metal oxide particles and MOFs surface can effectively tune the charge transfer efficiency of the material which leads to their third‐order NLO refraction signals. The interface inducement of CeO2‐shell to the MOF‐core also significantly changes their third‐order NLO properties compared to pure MOFs. This work provides new insights and efficient strategies for the development of new third‐order NLO materials with potential practical usage.

Solvothermal reactions of AgNO with N,N-bis(5-fluoropyridin-3-yl)succinamide (bfps) in MeCN afforded the one-dimensional cationic coordination polymer {[Ag(bfps)]NO} (1). Upon treatment of 1 with the anionic azo dye orange II (NaOII) in aqueous solution, the NO anions of 1 could be gradually exchanged by the OII anions via an anion-exchange process. The resulting OII anion-exchanged products {[Ag(bfps)](NO)(OII)} (2) and {[Ag(bfps)](NO)(OII)} (3) were formed by different molar ratios of 1 and the newly formed phase "{[Ag(bfps)](OII)}" (4), confirmed by PXRD patterns. Relative to those of the precursors 1 and NaOII, complexes 2 and 3 demonstrated enlarged photocurrent responses and reduced dielectric constants and dielectric losses, which could be correlated with the OII contents in their structures. Complex 3 acquired a stable anodic photocurrent of 12.06 μA, which was 4.9 times higher than that of 1. The dielectric constant (ε = 4.2) and dielectric loss (0.002) of 3 were nearly frequency independent in the range from 1 to 10 Hz. The results provide an interesting insight into the rational assembly of CP-dye complexes and their tunable optoelectronic applications.

Reactions of Zn­(OAc)2·2H2O with N 1,N 4-bis­(5-fluoropyridin-3-yl)­succinamide (bfps) and 1,2,3-benzenetricarboxylic acid (1,2,3-H3BTC) or 1,3,5-benzenetricarboxylic acid (1,3,5-H3BTC) under hydrothermal conditions produce two Zn­(II)-based coordination polymers (CPs), {[Zn3(bfps)­(1,2,3-BTC)2­(H2O)6]­·4H2O} n (1·4H2O) and {[Zn­(bfps)­(1,3,5-HBTC)]­·H2O} n (2·H2O). Both compounds show two-dimensional layer structures derived from interconnecting dinuclear [Zn2(1,2,3-BTC)2(H2O)2] units through the bfps bridges and the [Zn­(H2O)4] species (1·4H2O) or interlinking dinuclear [Zn2(1,3,5-HBTC)2] units via pairs of bfps bridges and pairs of 1,3,5-HBTC dianions (2·H2O). They display high absorptive capacities toward Orange IV (OIV) in water, i.e., 718 mg·g–1 (1·4H2O) and 794 mg·g–1 (2·H2O), respectively. The resulting CP-OIV composites with the chemical formulas of 1·2.0OIV (3) and 2·1.1OIV­·2.5H2O (4) exhibit enhanced photocurrent responses in relation to those of the two precursors.