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With the gradual exposure of energy problems and environmental pollution in modern society, electrochromic energy storage devices with the integration of smart windows and energy storage have become research hot spots in recent years. The multifunctional devices can be used as energy storage devices, and can also monitor the energy status in situ according to the color change. In this review, we introduce the working principle, device structure, and the possibility of the multi-functional combination of electrochromic energy storage devices. We also discuss, in detail, the candidate materials for electrochromic capacitors and electrochromic batteries in terms of design, synthesis, and application. Finally, we provide our own opinion on the development of the next generation multi-functional energy storage devices. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIBs) have been demonstrated as one of the most promising energy storage devices for applications in electric vehicles, smart grids, large-scale energy storage systems, and portable electronics. Compared with traditional inorganic compounds that often cause various environmental problems, organic electrode materials possess many advantages, such as the diversity of molecular structures, feasibility of subjective design, light weight, low cost, high theoretical capacity, and eco-friendliness, making them very promising in the application of energy-related devices. Among all organic materials used as electrodes for LIBs, organic carbonyl-based polymers with multi-electron reaction centers, high theoretical capacity, reaction reversibility, rapid redox kinetics, and the inhibition of electrolyte dissolution have recently become hot topics. In this review, we summarize the recent progress in the design, synthesis, and application of carbonyl-based polymers for LIBs. In addition, the advantages/disadvantages of individual materials are also discussed. [ABSTRACT FROM AUTHOR]

[Objectives] To identify the most suitable host plants for the development of Tetranychus urticae and Stethorus punctillum. [Methods] The developmental duration and fecundity of T. urticae, and the developmental duration, fecundity, hatching rate, pupation rate and eclosion rate of S. punctillum, were measured at a temperature of (25±1)°C and photoperiod of 14L : 10D, on different host plants. [Results] There were significant differences in the developmental duration of both species on different plants. The shortest developmental period of T. urticae was on peanut (9.82 d) and maximum fecundity of this species was recorded on peanuts and cowpeas. The developmental period of S. punctillum was shortest on peanut and cowpea (no significant difference), and highest on corn, peppers and eggplant. Fecundity of S. punctillum on the different banker plants was, peanut (112.60), cowpea (103.80), corn (85.20), pepper (68.20) and eggplant (53.40) and its adult eclosion rate on different banker plants was, peanut (80.11%), cowpea (70.26%), corn (66.66%), pepper (9.70%) and eggplant (29.81%). [Conclusion] Of the banker plants tested, peanut was the most suitable host for Tetranychus urticae and Stethorus punctillum. [ABSTRACT FROM AUTHOR]

Organometallic conjugated complexes have become an important type of stimuli-responsive materials because of their appealing electrochemical properties and rich photonic, electronic, and magnetic properties. They are potentially useful in a wide range of applications such as molecular wires, molecular switches, molecular machines, molecular memory, and optoelectronic detections. This review outlines the recent progress on the molecular design of carbometalated ruthenium and osmium complexes and their applications as redox-responsive materials with visible and near-infrared (NIR) absorptions and electron paramagnetic resonance as readout signals. Three molecule systems are introduced, including the symmetric diruthenium complexes, metal-amine conjugated bi-center system, and multi-center redox-active organometallic compounds. Because of the presence of a metal-carbon bond on each metal component and strong electronic coupling between redox sites, these compounds display multiple reversible redox processes at low potentials and each redox state possesses significantly different physical and chemical properties. Using electrochemical potentials as input signals, these materials show reversible NIR absorption spectral changes, making them potentially useful in NIR electrochromism and information storage. [ABSTRACT FROM AUTHOR]

In response to the application of low electrochemical potentials, ruthenium-tris(bipyridine) complexes decorated with multiple electron-rich and redox-active amine substituents show reversible absorption and emission spectral changes in the deep-red to NIR region. The number of amine substituents strongly affects the electrochemical and spectroscopic properties and the spin density distributions of the complex in the one-electron-oxidized state. [ABSTRACT FROM AUTHOR]

Monoamine 1, diamines 2- 4, triamine 5, and tetraamine 6 have been synthesized by substituting dianisylamino groups at the 1-, 3-, 6-, and/or 8-positions of pyrene. Diamines 2- 4 differ in the positions of the amine substituents. No pyrene-pyrene interactions are evident in the single-crystal packing of 3, 4, and 6. With increasing numbers of amine substituents, the first oxidation potential decreases progressively from the mono- to the tetraamine. These compounds show intense charge-transfer (CT) emission in CH2Cl2 at around 530 nm with quantum yields of 48-68 %. Upon stepwise oxidation by electrolysis or chemical oxidation, these compounds were transformed into radical cations 1⋅+- 6⋅+ and dications 22+- 62+, which feature strong visible and near-infrared absorptions. Time-dependent density functional theory studies suggested the presence of localized transitions from the pyrene radical cation and aminium radical cation, intervalence CT, and CT between the pyrene and amine moieties. Spectroscopic studies indicated that these radical cations and dications have good stability. Triamine 5 and tetraamine 6 formed efficient CT complexes with tetracyanoquinodimethane in solution. The results of EPR spectroscopy and density functional theory calculations suggested that the dications 22+- 42+ have a triplet ground state, whereas 52+ and 62+ have a singlet ground state. The dication of 1,3-disubstituted diamine 4 exhibits a strong EPR signal. [ABSTRACT FROM AUTHOR]

Nine cyclometalated ruthenium complexes with a redox-active diphenylamine unit in the para position to the RuC bond were prepared. MeO, Me, and Cl substituents on the diphenylamine unit and three types of auxiliary ligands-bis( N-methylbenzimidazolyl)pyridine (Mebip), 2,2′:6′,2′′-terpyridine (tpy), and trimethyl-4,4′,4′′-tricarboxylate-2,2′:6′,2′′-terpyridine (Me3tctpy)-were used to vary the electronic properties of these complexes. The derivative with an MeO-substituted amine unit and Me3tctpy ligand was studied by single-crystal X-ray analysis. All complexes display two well-separated redox waves in the potential region of +0.1 to +1.0 V versus Ag/AgCl, and the potential splitting ranges from 360 to 510 mV. Spectroelectrochemical measurements show that these complexes display electrochromism at low potentials and intense near-infrared (NIR) absorptions. In the one-electron oxidized form, the complex with the Cl-substituted amine unit and Mebip ligand shows a moderate ligand-to-metal charge transfer at 800 nm. The other eight complexes show asymmetric, narrow, and intense intervalence charge-transfer transitions in the NIR region, which are independent of the polarity of the solvent. The Mebip-containing complexes display rhombic or broad isotropic EPR signals, whereas the other seven complexes show relatively narrow isotropic EPR signals. In addition, DFT and time-dependent DFT studies were performed to gain insights into the spin distributions and NIR absorptions. [ABSTRACT FROM AUTHOR]

A ruthenium-bis-terpyridine complex [Ru(NPhtpy)(Ntpy)]2+(22+) with two redox-asymmetricamine units has been prepared, where NPhtpy is 4′-(di-p-anisylaminophen-4-yl)-2,2′:6′,2″-terpyridineand Ntpy is 4′-(di-p-anisylamino)-2,2′:6′,2″-terpyridine.This complex displays two consecutive redox couples at +0.82 and +1.02V vs Ag/AgCl, which are assigned to the N•+/0processesof the amine components of the NPhtpy and Ntpy ligands, respectively.The mono-oxidized complex 23+obtained byoxidative electrolysis shows the presence of the charge transfer fromruthenium(II) to the oxidized aminium radical cation of the NPhtpyligand (MNNPhtpyCT) around 1000 nm. In the dioxidized form(24+), the MNNPhtpyCT transitiondecreased distinctly and an opposite charge transfer from ruthenium(II)to the oxidized aminium radical cation of the Ntpy ligand (MNNtpyCT) appeared at 1380 nm. Complexes [Ru(NPhtpy)(tpy)]2+(tpy is 2,2′:6′,2″-terpyridine), [Ru(Ntpy)(tpy)]2+, and [Ru(NPhtpy)2]2+have been preparedand studied for the purpose of comparison. TDDFT calculations showthat the involvement of the intraligand charge transfer from bothNPhtpy and Ntpy ligands is responsible for the enhancement of thevisible absorptions of these complexes with respect to [Ru(tpy)2]2+. DFT and TDDFT calculations have been performedon 23+and 24+toprovide information on the spin distributions and the nature of thenear-infrared absorptions. Complex 23+showsan isotropic EPR signal at room temperature, consistent with an unpairedelectron localized on the nitrogen atom. [ABSTRACT FROM AUTHOR]

Four bis-tridentate ruthenium complexes with 5,5′′-divinyl-4′-tolyl-2,2′:6′,2′′-terpyridine (dvtpy) have been synthesized. Among them, 3(PF6) ([(dvtpy)Ru(Mebib)](PF6)) and 4(PF6) ([(dvtpy)Ru(dpb)](PF6)) are cyclometalated, and 5(PF6)2 ([(dvtpy)Ru(Mebip)](PF6)2) and 6(PF6)2 ([(dvtpy)Ru(tpy)](PF6)2) are noncyclometalated, where Mebib is 2-deprotonated-1,3-bis(N-methylbenzimidazolyl)benzene, dpb is 2-deprotonated-1,3-di(2-pyridyl)benzene, Mebip is 2,6-bis(N-methylbenzimidazolyl)pyridine, and tpy is 2,2′:6′,2′′-terpyridine, respectively. Reductive electropolymerization of these complexes and copolymerization of 4(PF6) and 5(PF6)2 proceeded smoothly, both on glassy carbon and ITO glass electrodes, to afford stable metallopolymeric films with well-defined redox processes. On the basis of the monomer structures, electrochemical properties, and polymerization mechanism, the polymer chains of these materials are supposed to be composed of organic frameworks with the metal ions laterally chelated to the main backbones. The polymeric films on ITO surfaces display promising electrochromism in the visible region with good reversibility and moderate contrast ratio. Besides, the apparent diffusion constants of films of 3(PF6)–6(PF6)2 were measured by potential step chronoamperometry and the typical surface morphology of poly-5(PF6)2/ITO film was studied using SEM. [ABSTRACT FROM AUTHOR]

Two series of linear ruthenium coordination oligomers, [(Ntpy)Ru n(tppz) n−1(tpy)]2 n+ (mono-Ntpy series, n=1-3) and [(Ntpy)2Ru n(tppz) n−1]2 n+ (bis-Ntpy series, n=1-3) have been prepared, where Ntpy is the capping ligand 4′-di- p-anisylamino-2,2′:6′,2′′-terpyridine, tppz is tetra-2-pyridylpyrazine, and tpy is 2,2′:6′,2′′-terpyridine. The electrochemical measurements evidence oxidation events from both the amine segments and the metal centers and reduction waves from tppz and the capping ligands. Both series complexes display much enhanced light absorption with respect to model complexes without terminal amine units. Density functional theory (DFT) calculations have been performed on both series and time-dependent DFT (TD-DFT) calculations have been performed on the bis-Ntpy-series compounds ( n=1-4) to characterize their electronic structures and excited states and predict the electronic properties of long-chain polymers. Upon one-electron oxidation, the mono-Ntpy-series monoruthenium and diruthenium complexes display N+-localized transitions and metal-to-nitrogen charge-transfer (MNCT) transitions in the near-infrared (NIR) region. DFT and TD-DFT computations on the one-electron-oxidized forms of the mono-Ntpy-series compounds ( n=1-4) provide insight into the nature of the MNCT transitions and the degree of charge delocalization. [ABSTRACT FROM AUTHOR]

Electron delocalization of new mixed-valent (MV) systems with the aid of lateral metal chelation is reported. 2,2′-Bipyridine (bpy) derivatives with one or two appended di- p-anisylamino groups on the 5,5′-positions and a coordinated [Ru(bpy)2] (bpy=2,2′-bipyridine), [Re(CO)3Cl], or [Ir(ppy)2] (ppy=2-phenylpyridine) component were prepared. The single-crystal molecular structure of the bis-amine ligand without metal chelation is presented. The electronic properties of these complexes were studied and compared by electrochemical and spectroscopic techniques and DFT/TDDFT calculations. Compounds with two di- p-anisylamino groups were oxidized by a chemical or electrochemical method and monitored by near-infrared (NIR) absorption spectral changes. Marcus-Hush analysis of the resulting intervalence charge-transfer transitions indicated that electron coupling of these mixed-valent systems is enhanced by metal chelation and that the iridium complex has the largest coupling. TDDFT calculations were employed to interpret the NIR transitions of these MV systems. [ABSTRACT FROM AUTHOR]

In situ one-pot rapid layer-by-layer assembly of polymeric films as an active layer of a photoactive device via alternation of reductive and oxidative electropolymerization has been demonstrated. This novel fabrication without moving or changing experimental gears would be a powerful strategy to develop automated layer-by-layer machines. [ABSTRACT FROM AUTHOR]