We report the electrochemiluminescence properties of square-planar Pt(II) complexes that result from the formation of supramolecular nanostructures. We define this new phenomenon as aggregation-induced electrochemiluminescence (AIECL). In this system, self-assembly changes the HOMO and LUMO energies, making their population accessible via ECL pathways and leading to the generation of the luminescent excited state. Significantly, the emission from the self-assembled system is the first example of electrochemiluminescence (ECL) of Pt(II) complexes in aqueous solution having higher efficiency than the standard, Ru(bpy).The finding can lead to a new generation of bright emitters that can be used as ECL labels.

Amine-rich nitrogen-doped carbon nanodots (NCNDs) have been successfully used as co-reactant in electrochemiluminescence (ECL) processes. Primary or tertiary amino groups on NCNDs have been studied as co-reactant sites for Ru(bpy) ECL, showing their eligibility as powerful alternatives to tripropylamine (TPrA). We also report the synthesis and ECL behavior of a new covalently linked hybrid of NCNDs and Ru(bpy) . Notably, the NCNDs in the hybrid act both as carrier for ECL labels and as co-reactant for ECL generation. As a result, the hybrid shows a higher ECL emission as compared to the combination of the individual components, suggesting the self-enhancing ECL of the ruthenium complex due to an intramolecular electron transfer process.

A new strategy to create iridium(iii)-based ECL labels reveals limitations of conventional approaches.

Miniaturized structures that can move in a controlled way in solution and integrate various functionalities are attracting considerable attention due to the potential applications in fields ranging from autonomous micromotors to roving sensors. Here we introduce a concept which allows, depending on their specific design, the controlled directional motion of objects in water, combined with electronic functionalities such as the emission of light, sensing, signal conversion, treatment and transmission. The approach is based on electric field-induced polarization, which triggers different chemical reactions at the surface of the object and thereby its propulsion. This results in a localized electric current that can power in a wireless way electronic devices in water, leading to a new class of electronic swimmers (e-swimmers).

Amine-richn itrogen-doped carbon nanodots (NCNDs) have been successfully used as co-reactant in electrochemiluminescence (ECL) processes.P rimary or tertiary amino groups on NCNDs have been studied as coreactant sites for Ru(bpy) 3 2+ ECL, showing their eligibility as powerful alternatives to tripropylamine (TPrA). We also report the synthesis and ECL behavior of an ew covalently linked hybrid of NCNDs and Ru(bpy) 3 2+.Notably,the NCNDs in the hybrid act both as carrier for ECL labels and as co-reactant for ECL generation. As ar esult, the hybrid shows ah igher ECL emission as compared to the combination of the individual components,s uggesting the self-enhancing ECL of the ruthenium complex due to an intramolecular electron transfer process.Carbon nanodots (CNDs), quasi-spherical nanoparticles with size below 10 nm, [1][2][3] are expected to have ah uge impact in biotechnological and environmental applications, based on their high potential as an ontoxic,f luorescent alternative to the popular semiconductor-based quantum dots (QDs). [4,5] In addition, properties such as water solubility, chemical inertness,facile modification and high resistance to photobleaching [3,4, 6] are important for their analytical and bioanalytical applications. [1,4,5] In this latter fields,e lectrochemiluminescence (ECL) is becoming an increasingly popular biosensing technique.E CL is ar edox-induced light emission in which high-energy species,g enerated at the electrodes,u ndergo ah igh-energy electron transfer reaction forming an excited state that emits light. [7] Thee xcited state can be produced through the reaction of radicals generated from the same chemical species (emitter), in the so-called annihilation mechanism, or from two different precursors (emitter and co-reactant), via co-reactant ECL. [7,8] In the annihilation mechanism, the application of oxidative conditions to al uminophore followed by reductive conditions (or viceversa), generates high-energy species that react with one another producing ECL emission. In contrast, in co-reactant ECL, both luminophore and co-reactant are first oxidized or reduced at the electrodic surface forming radicals and intermediate states.T he co-reactant radical oxidizes or reduces the luminophore producing its excited state.T hus, depending on the nature of the co-reactant, both "oxidativereduction" or "reductive-oxidation" mechanisms are possible.The main advantage of the co-reactant pathway is that the formation of radicals in aqueous solutions,a nd the consequent generation of ECL, is attainable without potential cycling and at less extreme potentials compared to common organic solvents,o pening up aw ide range of bioanalytical applications. [7] Them ost employed ECL luminophore is ruthenium(II) tris(2,2'-bipyridyl) (Ru(bpy) 3 2+

The heterofunctional and rigid ligand N,N'-diphosphanyl-imidazol-2-ylidene (PCNHCP; P = P(t-Bu)2), through its phosphorus and two N-heterocyclic carbene (NHC) donors, stabilizes trinuclear chain complexes, with either Au3 or AgAu2 cores, and dinuclear Au2 complexes. The two oppositely situated PCNHCP (L) ligands that "sandwich" the metal chain can support linear and rigid structures, as found in the known tricationic Au(I) complex [Au3(μ3-PCNHCP,κP,κCNHC,κP)2](OTf)3 (OTf = CF3SO3; [Au3L2](OTf)3; Chem. Commun. 2014, 50, 103-105) now also obtained by transmetalation from [Ag3(μ3-PCNHCP,κP,κCNHC,κP)2](OTf)3 ([Ag3L2](OTf)3), or in the mixed-metal tricationic [Au2Ag(μ3-PCNHCP,κP,κCNHC,κP)2](OTf)3 ([Au2AgL2](OTf)3). The latter was obtained stepwise by the addition of AgOTf to the digold(I) complex [Au2(μ2-PCNHCP,κP,κCNHC)2](OTf)2 ([Au2L2](OTf)2). The latter contains two dangling P donors and displays fluxional behavior in solution, and the Au···Au separation of 2.8320(6) Å in the solid state is consistent with metallophilic interactions. In the solvento complex [Au3Cl2(tht)(μ3-PCNHCP,κP,κCNHC,κP)](OTf)·MeCN ([Au3Cl2(tht)L](OTf)·MeCN), which contains only one L and one tht ligand (tht = tetrahydrothiophene), the metal chain is bent (148.94(2)°), and the longer Au···Au separation (2.9710(4) Å) is in line with relaxation of the rigidity due to a more "open" structure. Similar features were observed in [Au3Cl2(SMe2)L](OTf)·2MeCN. A detailed study of the emission properties of [Au3L2](OTf)3, [Au3Cl2(tht)L](OTf)·MeCN, [Au2L2](OTf)2, and [Au2AgL2](OTf)3 was performed by means of steady state and time-resolved photophysical techniques. The complex [Au3L2](OTf)3 displays a bright (photoluminescence quantum yield = 80%) and narrow emission band centered at 446 nm with a relatively small Stokes' shift and long-lived excited-state lifetime on the microsecond timescale, both in solution and in the solid state. In line with the very narrow emission profile centered in the violet-blue region, fabrication of organic light-emitting devices (OLEDs) comprising the [Au3L2](OTf)3 complex demonstrated its usefulness as a deep-blue emitter in solution-processed OLEDs. Electrochemical and Raman spectroscopic studies were also performed on [Au3L2](OTf)3. Experimental results were rationalized by means of Wave-Function Theory (WFT) and Density Functional Theory (DFT). MP2 calculations gave a satisfactory description of the structures of the cationic complexes [Au3L2](3+) and [Au2L2](2+) and pointed to Au···Au interactions having an electrostatic component owing to the dissimilar charge distribution in the chain caused by the heterofunctional ligand. The nature of the emitting states and their geometric distortions relative to the ground states in [Au3L2](3+) and [Au2L2](2+) was studied by DFT, revealing contraction of the Au···Au distances and coordination geometry changes by association of the dangling P donor, respectively.

We report a new approach to heavy metal ion detection based on bipolar electrochemiluminescence (BP-ECL), which is simple and low cost yet highly sensitive.

A new class of redox metallopolymer based on cyclometalated iridium(III) centers is described, with unusually intense luminescence properties in aqueous media. We report the facile synthesis, photophysical and electrochemical characterization, supported by DFT calculations and their electrochemiluminescence (ECL) properties which, under some circumstances, are significantly greater than the analogous ruthenium-based materials. The photoluminescence (PL) and ECL of these materials are further dramatically enhanced when dispersed or immobilized as polymeric nanoparticles (PNPs). This aggregation-induced emission (AIE and AIECL) operates by providing important protection for the cyclometalated iridium(III) centers against the types of quenching processes which commonly afflict iridium-based luminophores in aqueous media. The results suggest interesting new avenues of research for the application of such materials in and PL and ECL-based detection and imaging as well as light-emitting devices.