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The interfacial electronic structure between oxide thin films and organic semiconductors remains a key parameter for optimum functionality and performance of next-generation organic/hybrid electronics. By tailoring defect concentrations in transparent conductive ZnO films, we demonstrate the importance of controlling the electron transfer barrier at the interface with organic acceptor molecules such as C₆₀. A combination of electron spectroscopy, density functional theory computations, and device characterization is used to determine band alignment and electron injection barriers. Extensive experimental and first principles calculations reveal the controllable formation of hybridized interface states and charge transfer between shallow donor defects in the oxide layer and the molecular adsorbate. Importantly, it is shown that removal of shallow donor intragap states causes a larger barrier for electron injection. Thus, hybrid interface states constitute an important gateway for nearly barrier-free charge carrier injection. These findings open new avenues to understand and tailor interfaces between organic semiconductors and transparent oxides, of critical importance for novel optoelectronic devices and applications in energy-conversion and sensor technologies.

Controlling the defect composition of the oxide surface allows the barriers to be changed for charge transfer at the ZnO/Fullerene interface. Direct and inverse electron spectroscopy is used to demonstrate the control over the transfer barrier by tracking electronic alignment and interface state formation. This is predicted by DFT and leads to observable alterations in charge injection in our devices.

Three examples of the rare 8,1,2-closo-MC₂B₉ isomeric form of an icosahedral metallacarborane have been isolated as unexpected trace products in reactions. Seeking to understand how these were formed we considered both the nature of the reactions that were being undertaken and the nature of the coproducts. This led us to propose a mechanism for the formation of the 8,1,2-closo-MC₂B₉ species. The mechanism was then tested, leading to the first deliberate synthesis of an example of this isomer. Thus, deboronation of 4-(η-C₅H₅)-4,1,8-closo-CoC₂B₁₀H₁₂ selectively removes the B5 vertex to yield the dianion [nido-(η-C₅H₅)CoC₂B₉H₁₁]²⁻, oxidative closure of which affords 8-(η-C₅H₅)-8,1,2-closo-CoC₂B₉H₁₁ in moderate yield.

The crystallographic characterization of three new examples of metallacarboranes with 8,1,2-closo-MC₂B₉ structure is reported. Consideration of the reactions in which they were formed as well as their coproducts led to a suggested mechanism. This mechanism was tested in the synthesis of 8-(η-C₅H₅)-8,1,2-closo-CoC₂B₉H₁₁ and found to be successful.

A triad of complementary techniques, namely high-resolution gas adsorption coupled with hysteresis scanning and density functional theory, rotation electron diffraction, and electron tomography, has revealed the intracrystalline nature and connectivity of size-tailored mesopores in surfactant-templated mesostructured zeolite-Y with new clarity. This approach constitutes a significant advance in the elucidation of the structure of nanoporous solids.

Band-selective infrared photodetectors (PDs) are constructed with InAs_xP_1-x alloy nanowires from the complete composition range (0 ≤ x ≤ 1) achieved by a new growth route combining the vapor–liquid–solid mechanism with an additional ion-exchange process. Increasing the composition x value from 0 to 1 in the PDs allows the peak response wavelength to be gradually tuned from ca. 900 to ca. 2900 nm.

A self-adhesive laminate solar-cell electrode is presented based on a metal grid embedded in a polymer film (x–y conduction) and set in contact with the active layer using a pressure-sensitive adhesive containing a very low quantity (1.8%) of organic conductor, which self-organizes to provide z conduction to the grid. This ITO-free material performs in an identical fashion to evaporated gold in high-efficiency perovskite solar cells.

A conceptually new all-solid-state asymmetric supercapacitor based on atomically thin sheets is presented which offers the opportunity to optimize supercapacitor properties on an atomic level. As a prototype, β-Co(OH)₂ single layers with five-atoms layer thickness were synthesized through an oriented-attachment strategy. The increased density-of-states and 100 % exposed hydrogen atoms endow the β-Co(OH)₂ single-layers-based electrode with a large capacitance of 2028 F g⁻¹. The corresponding all-solid-state asymmetric supercapacitor achieves a high cell voltage of 1.8 V and an exceptional energy density of 98.9 Wh kg⁻¹ at an ultrahigh power density of 17 981 W kg⁻¹. Also, this integrated nanodevice exhibits excellent cyclability with 93.2 % capacitance retention after 10 000 cycles, holding great promise for constructing high-energy storage nanodevices.

An atomically thin β-Co(OH)₂ sheet electrode was used to fabricate an all-solid-state asymmetric supercapacitor with high energy density. The β-Co(OH)₂ layers are characterized by 100 % exposed hydrogen atoms, thus facilitating efficient Faradaic redox reactions. The energy density of 98.9 Wh kg⁻¹ can compete with the world's highest energy density for supercapacitors.

The easy and effective separation of proteins from a mixture is crucial in proteomics. A supramolecular method is described to selectively capture and precipitate one protein from a protein mixture upon application of a magnetic field. A multivalent complex self-assembles in a dilute aqueous solution of three components: magnetic nanoparticles capped with cyclodextrin, non-covalent cross-linkers with an adamantane and a carbohydrate moiety, and lectins. The self-assembled ternary complex is precipitated in a magnetic field and readily redispersed with the aid of a non-ionic surfactant and competitive binding agents. This strategy to purify proteins by supramolecular magnetic precipitation is highly selective and efficient.

Separation by attraction: Proteins can be precipitated with a magnetic field by formation of a multivalent self-assembled complex from cyclodextrin-coated magnetic nanoparticles (MNPs), adamantane- and carbohydrate-functionalitzed non-covalent cross-linkrs, and lectin. This supramolecular approach to purify proteins is highly selective and efficient.

Complex hollow structures of metal sulfides could be promising materials for energy storage devices such as supercapacitors and lithium-ion batteries. However, it is still a great challenge to fabricate well-defined metal sulfides hollow structures with multi-shells, hierarchical architectures, and non-spherical shape. In this work, a template-engaged strategy is developed to synthesize hierarchical NiS box-in-box hollow structures with double-shells. The NiS box-in-box hollow structures constructed by ultrathin nanosheets are evaluated as electrode materials for supercapacitors. As expected, the NiS box-in-box hollow structures exhibit excellent rate performance and impressive cycling stability due to their unique nano-architecture. More importantly, the synthetic method can be easily extended to synthesize other transition metal sulfides box-in-box hollow structures. For example, we have also successfully synthesized similar CuS and MnS box-in-box hollow structures. The present work makes a significant contribution to the design and synthesis of transition metal sulfides hollow structures with non-spherical shape and complex architecture, as well as their potential applications in electrochemical energy storage.

Box in box: A template-engaged method is successfully developed to synthesize hierarchical metal sulfide (NiS, CuS, MnS) box-in-box hollow structures with double-shells. As an example, it is demonstrated that the NiS box-in-box hollow structure exhibits excellent pseudocapacitive performance with remarkable rate performance and cycling stability.

Nature’s enzymes are an ongoing source of inspiration for scientists. The complex processes behind their selectivity and efficiency is slowly being unraveled, and these findings have spawned many biomimetic catalysts. However, nearly all focus on the conversion of small molecular substrates. Nature itself is replete with inventive catalytic systems which modify, replicate, or decompose entire polymers, often in a processive fashion. Such processivity can, for example, enhance the rate of catalysis by clamping to the polymer substrate, which imparts a large effective molarity. Reviewed herein are the various strategies for processivity in nature’s arsenal and their properties. An overview of what has been achieved by chemists aiming to mimic one of nature’s greatest tricks is also included.

Hold the line: In processive catalysis, a catalyst binds to its substrate and performs multiple rounds of catalysis before dissociation. Nature leverages this phenomenon in its synthesis or processing of biopolymers. Processivity allows the achievement of rates of catalysis which cannot be matched by distributive systems. This Minireview describes processive catalysis and the advances that have been made in emulating it through supramolecular chemistry.