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A new method in which supramolecular polymerization is promoted and controlled through self-sorting is reported. The bifunctional monomer containing p-phenylene and naphthalene moieties was prepared. Supramolecular polymerization is promoted by selective recognition between the p-phenylene group and cucurbit[7]uril (CB[7]), and 2:1 complexation of the naphthalene groups with cucurbit[8]uril (CB[8]). The process can be controlled by tuning the CB[7] content. This development will enrich the field of supramolecular polymers with important advances towards the realization of molecular-weight and structural control.

Development of power conversion efficiency (PCE) and short-term stability are still huge challenges that restrict the actual industrialization of OSCs. [5,6] There has been much exploration of the state-of-art photovoltaic performance, with methods that mainly concentrate on the molecular design, structure modification of devices, and the construction of active layers. [7][8][9] Through innovative molecular design and matching with suitable donors, the Y6 system has opened a new vista in which the efficiency of nonfullerene solar cells (NFSC) approached 16%. [10] To date, subsequent optimizations have brought a brighter future with the PCE in single-junction devices exceeding 18%. [11][12][13][14] Together with molecular innovation, interface engineering also improves the device performances continually. Gene rally, interface engineering implies that through insertion of a single or double interlayer between an active layer and a cathode or anode to improve the indirect contact between them, and further regulation of the morphology or work function of electrodes, the devices can be improved. Included amongst the most popular interfacial materials, there are several main types: [15] metal oxides (MO), including the commonly used ZnO [16] and MoOx, alcohol-soluble polymers and small molecules such as amino PDINO [17] and PFN-Br, [18] Interface engineering is a critical method by which to efficiently enhance the photovoltaic performance of nonfullerene solar cells (NFSC). Herein, a series of metal-nanographene-containing large transition metal involving d π -p π conjugated systems by way of the addition reactions of osmapentalynes and p-diethynyl-hexabenzocoronenes is reported. Conjugated extensions are engineered to optimize the π-conjugation of these metal-nanographene molecules, which serve as alcohol-soluble cathode interlayer (CIL) materials. Upon extension of the π-conjugation, the power conversion efficiency (PCE) of PM6:BTP-eC9-based NFSCs increases from 16% to over 18%, giving the highest recorded PCE. It is deduced by X-ray crystallographic analysis, interfacial contact methods, morphology characterization, and carrier dynamics that modification of hexabenzocoronenes-styryl can effectively improve the short-circuit current density (J sc ) and fill factor of organic solar cells (OSCs), mainly due to the strong and ordered charge transfer, more matching energy level alignments, better interfacial contacts between the active layer and the electrodes, and regulated morphology. Consequently, the carrier transport is largely facilitated, and the carrier recombination is simultaneously impeded. These new CIL materials are broadly able to enhance the photovoltaic properties of OSCs in other systems, which provides a promising potential to serve as CILs for higher-quality OSCs.

Artificial nanochannels, inheriting smart gating functions of biological ion channels, promote the development of artificial functional nanofluidic devices for high-performance biosensing and electricity generation. However, gating states of the artificial nanochannels have been mainly realized through chemical modification of the channels with responsive molecules, and their gating states cannot be further regulated once the nanochannel is modified. In this work, we employed a new supramolecular layer-by-layer (LbL) self-assembly method to achieve reversible and adjustable multiple gating features in nanofluidic diodes. Initially, a self-assembly precursor was modified into a single conical nanochannel, then host molecule-cucurbit[8]uril (CB[8]) and guest molecule, a naphthalene derivative, were self-assembled onto the precursor through an LbL method driven by host-enhanced π-π interaction, forming supramolecular monolayer or multilayers on the inner surface of the channel. These self-assemblies with different layer numbers possessed remarkable charge effects and steric effects, exhibiting a capability to regulate the surface charge density and polarity, the effective diameter, and the geometric asymmetry of the single nanochannel, realizing reversible gating of the single nanochannel among multiple rectification and ion-conduction states. As an example of self-assembly of supramolecular networks in nanoconfinements, this work provides a new approach for enhancing functionalities of artificial nanochannels by LbL supramolecular self-assemblies. Meanwhile, since the host molecule, CB[8], used in this work can interact with different kinds of biomolecules and stimuli-responsive chemical species, this work can be further extended to build a novel stable multiple-state research platform for a variety of uses such as sensing and controllable release.