Proses Produksi Dan Pengemasan Yoghurtdicv. Cita Nasional Salatiga

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Quadrites and Crossed-Chain Crystal Structures in Polymer Semiconductors

Many high-performance conjugated polymers for organic photovoltaics and transistors crystallize such that chains are parallel, resulting in significant anisotropy of the nanoscale charge transport properties. Here we demonstrate an unusual intercrystallite relationship where thin lamellae adopt a preferred epitaxial relationship with crossed-chains at the interface. The crossed-chains may allow either crystal to use the other as an “electronic shunt”, creating efficient quasi-three-dimensional transport pathways that reduce the severity of grain boundaries and defects in limiting transport

Mithrene Is a Self-Assembling Robustly Blue Luminescent Metal–Organic Chalcogenolate Assembly for 2D Optoelectronic Applications

Crystalline metal–organic chalcogenolate assemblies are a class of semiconducting hybrid nanomaterials that consist of well-defined arrays of nanostructured inorganic coordination polymers with a supramolecular lattice of organic ligands. Growing crystals of periodic arrays of nanostructured hybrid chalcogenolates at biphasic liquid–liquid interfaces has been used to prepare semiconducting hybrid materials for potential applications in sensing, catalysis, mechanochemistry, organic light-emitting devices, and photovoltaics. However, a distinct lack of a systematic framework for quantifying the relationship between experimental parameters and the structure–function relationship of the prepared materials has been one of the largest hurdles for the emerging field of hybrid chalcogenolates and related hybrid coordination polymer systems. Here we examine the crystallization of silver benzeneselenolate, coined here as mithrene, at a toluene–water interface and demonstrate that silver ion concentration is the critical variable for controlling the morphology of the semiconducting crystals. Confocal microscopy is used to demonstrate that the blue luminescence of the material is robust across all morphologies. The role of metal ion concentration on the structure and morphology of the hybrid chalcogenolate is considered, and the properties of the crystalline and amorphous products are compared. Grazing-incidence wide-angle X-ray scattering is used to demonstrate that the crystallographic phase of the crystals in sparse layers is uniform across all morphologies. The observation of blue luminescence can be used as a reliable proxy for the crystalline phase in future work. The straightforward synthetic preparation for and robust optoelectronic properties of silver benzene­selenolate make it an ideal model system for the development of device and sensor applications leveraging the emerging class of metal–organic chalcogenolates

Molecular Engineering for Large Open-Circuit Voltage and Low Energy Loss in Around 10% Non-fullerene Organic Photovoltaics

Recent efforts in organic photovoltaics (OPVs) have been devoted to obtaining low-bandgap non-fullerene acceptors (NFAs) for high photocurrent generation. However, the low-lying lowest unoccupied molecular orbital (LUMO) level in narrow bandgap NFAs typically results in a small energy difference (Δ<i>E</i>_DA) between the LUMO of the acceptor and the highest occupied molecular orbital (HOMO) of the donor, leading to low open-circuit voltage (<i>V</i>_OC). The trade-off between Δ<i>E</i>_DA and photocurrent generation significantly limits the simultaneous enhancement of both <i>V</i>_OC and short-circuit current density (<i>J</i>_SC). Here, we report a new medium-bandgap NFA, IDTT-T, containing a weakly electron-withdrawing <i>N</i>-ethyl thiabarbituric acid terminal group on each end of the indacenodithienothiophene (IDTT) core. When paired with a benchmark low-bandgap PTB7-th polymer donor, simultaneous enhancement of both Δ<i>E</i>_DA and absorption spectral coverage was realized. The OPV devices yield a <i>V</i>_OC of 1.01 V, corresponding to a low energy loss of 0.57 eV in around 10% efficiency single-junction NFA OPVs. The design demonstrates a working principle to concurrently increase Δ<i>E</i>_DA and photocurrent generation for high <i>V</i>_OC and PCE in bulk fullerene-free heterojunction OPVs

A Modular Strategy for Fully Conjugated Donor–Acceptor Block Copolymers

A novel strategy for the synthesis of fully conjugated donor–acceptor block copolymers, in a single reaction step employing Stille coupling polymerization of end-functional polythiophene and AA + BB monomers, is presented. The unique donor–acceptor structure of these block copolymers provides a rich self-assembly behavior, with the first example of a fully conjugated donor–acceptor block copolymer having two separate crystalline domains being obtained