Five members of a new family of polyoxometalate (POM)-ligated trinuclear lanthanoid (Ln) clusters with the general formula K20Li2[Ln3(μ3-OH)(H2O)8(AsW9O33)(AsW10O35(mal))]2·17H2O [Ln = Dy (1Dy), Tb (2Tb), Gd (3Gd), Eu (4Eu), and Sm (5Sm), mal = malate] have been synthesized, all of which consist of the dimeric {[Ln3(μ3-OH)(H2O)8(AsW9O33)[AsW10O35(mal)]}(11-) polyanion constructed from a {AsW9O33} and a {AsW10O35(mal)} building block linked by a tri-Ln cluster [Ln3(μ3-OH)(H2O)8](8+), where the two malate ligands play a key bridging role. The {AsW10O35(mal)} subunit can be viewed as the {AsW9O33} building block anchoring an additional tungsten center [WO2(mal)]. The electrospray ionization mass (ESI-MS) spectra indicate that the dimeric fragments of 1Dy and 2Tb are unstable, which are apt to produce the subunit [KH5Ln3(OH)(H2O)(AsW9O33)2](4-) in solution. The solid-state photoluminescence measurements display the yellowish green emission for 1Dy and 5Sm, green emission for 2Tb and reddish orange emission for 4Eu, which are attributed to the Ln(III) f-f electron transitions. Magnetic property studies indicate that 1Dy displays probable SMM behaviour with slow magnetization relaxation, whereas the weak antiferromagnetic interactions exist in two {Ln3} clusters for 2Tb-5Sm.

It is challenging to explore and prepare high-nuclear lanthanide (Ln) cluster-encapsulated polyoxometalates (POMs). Herein, we fabricate an unprecedented Ce10-cluster-embedded polyoxotungstate (POT) (TMA)14H2[Ce(III)(H2O)6]{[Ce(IV)7Ce(III)3O6(OH)6(CO3)(H2O)11][(P2W16O59)]3}·41H2O (1) (TMA = tetramethyleneamine) by coordination-driven self-assembly strategy, which contains the largest Ce cluster [Ce(IV)7Ce(III)3O6(OH)6(CO3)(H2O)11] (Ce10) in all the Ln-containing POM chemistry to date. Self-assembly of the in situ dilacunary [P2W16O59](12-) fragments and mixed Ce(3+) and Ce(4+) ions by means of coordination-driven force results in a novel 2D graphite-like framework constructed from mixed-valent cerium(III/IV) cluster {Ce10} encapsulated poly(POT) units and Ce(3+) ions. The most remarkable feature is that the skeleton of the centrosymmetric Ce10-cluster-embedded POT trimer contains three dilacunary [P2W16O59](12-) fragments trapping a novel {Ce10} cluster via 18 terminal-oxo and three μ4-oxo atoms.

Herein, a novel polyaspartic acid derivative, polyaspartic acid/2-amino-2-methyl-1-propanol graft copolymer (PASP/AMP), was synthesized via a ring-opening reaction using polysuccinimide (PSI) and 2-amino-2-methyl-1-propanol (AMP). The structure of PASP/AMP was characterized via 1 H NMR and FTIR.Its scale and corrosion inhibition performances were investigated via static and weight loss tests, respectively. Additionally, its biodegradability was assessed by measuring its chemical oxygen demand.The influence of PASP/AMP on scale deposition was observed via scanning electron microscopy (SEM) and X-ray powder diffraction (XRD). The maximum scale inhibition efficiency of 100% for PASP/AMP against CaCO 3 , CaSO 4 , and Ca 3 (PO 4 ) 2 was achieved at the concentrations of 1, 4, and 14 mg L À1 , respectively. Its corrosion inhibition efficiency for carbon steel is close to 28% at 24 mg L À1. The degradation rate of PASP/AMP could reach up to 65% within 28 days. According to the SEM images and XRD spectra, the scale deposits become irregular and distorted in shape, which can easily be dispersed by flowing water. This study demonstrates that PASP/AMP as a biodegradable inhibitor exhibits better scale and corrosion inhibition performances as compared to PASP and shows promising prospect for application.

It is found by experiment that the cationic halogen bond donors (cationic iodoimidazolium compounds) can activate the Ritter-type solvolysis of benzhydryl bromide, while the cationic hydrogen bond donors (cationic imidazolium compounds) could not. To understand the activation mechanism, various noncovalent interactions between benzhydryl bromide and a series of activators in solution, including halogen bond, hydrogen bond, lone pair···π/π + , and C–H···π/π + , were explored theoretically. Our study revealed that the activation difference can be contributed by the variation of the noncovalent interactions. For halogen bond donors, the successful activation is attributed by halogen bond and lone pair···π. The halogen bonds mainly provide the stabilization energy of the ion-pair complex with the help of lone pair···π. For hydrogen-bond donors, the contribution of the hydrogen bond is unable to compensate the like-charge repulsion arising from the generation of the carbocation, leading to the unsuccessful activation. In general, lone pair···π makes a difference.

Graphite anodes in commercialized lithium ion batteries are meeting the bottleneck for future high-performance electronic devices. Strategies has been applied to improve the cycle and rate capacity of the anode active materials. Herein, a two-step hydrothermal approach is presented to synthesize TiO2@MoS2/C as enhanced anodic electrode. The TiO2@MoS2/C electrode delivers a satisfying cycle performance of 643.4 mAh/g on average at a current of 100 mA/g upon 100 cycles. The comparison study shows that TiO2@MoS2/C are superior to its individual part when assembled into batteries. The result also demonstrates that the support from TiO2 nanosheet arrays is essential to achieve both improved cycle and rate performance. Without TiO2 scaffold as an intermediate, MoS2/C is not able to firmly attach to Ti substrate and tends to be exfoliated upon cycling. Besides, the presence of carbon remarkably improves the poor conductivity of TiO2 and MoS2, which is beneficial to elevate rate capacity at high currents.Keywords：TiO2@MoS2/C; carbon infused MoS2; TiO2 nanosheet arrays; intensified anodes