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Precise control of the interior and outer shapes of polymer nanoparticles has found broad interest in nanosciences, for example, in fundamental studies of their physical properties, colloidal behavior, and corresponding applications. Realizing such control below the 50 nm scale (i.e., a size scale close to individual polymer chains) requires accurate manipulation of polymerization techniques and a judicious choice of the chemical structure in monomers and/or polymers. Here, we constructed a series of well-defined sub-50 nm homopolymer nanoparticles with controllable shape and highly ordered, complex internal structures with sub-5 nm domain spacings, starting from 1-vinyl-1,2,4-triazolium-type ionic liquids in a one-pot dispersion polymerization. With cryogenic electron microscopy and tomography, a morphological evolution of particle shape and interior at this extremely small size end, unusual for polymer colloids, was identified and investigated in detail.

covalently bonded organic moieties. Because of their unique properties derived from their tunable porous structures and the multiple functional groups, which can be included in their backbones, POPs have been actively investigated for multiple applications including gas storage/separation, [2,3] catalysis, [4][5][6] optoelectronics, [7,8] sensing, [9][10][11] energy storage, and conversion. [12,13] Aside from their high specific surface areas, they furthermore show excellent chemical stability, light-weight and a versatile chemistry for modification and functionalization. POPs can be further classified into two categories based on their crystallinity. Crystalline POPs are usually summarized under the name covalent organic frameworks [14][15][16] (COFs). Amorphous POPs are further divided, based on their structure or construction principles into hyper-crosslinked polymers [17,18] (HCPs), polymers of intrinsic microporosity [19,20] (PIMs), porous aromatic frameworks [21,22] (PAFs), and others. Recent research has seen increasing interest on amorphous POPs, especially when their skeleton is π-conjugated. In these highly porous networks, π-conjugation is superimposed with meso-/microporosities, i.e., electron transport in the polymer backbone is accompanied by mass transport in the porous system, which enable many intriguing properties and applications, e.g., in energy storage and conversion, [23,24] or optoelectronics. [25,26] As such, the importance of π-conjugation in porous polymer networks has defined another emerging functional POP class-the conjugated microporous polymers (CMPs). As mentioned, such CMPs [27] are a unique class of POPs exhibiting extended π-conjugated structures and permanent nanopores (Table S1). Earlier, McKeown et al. [28] discussed an important concept of preparing robust nanoporous materials by the covalent binding of planar molecules via a rigid spirocyclic linker. In 2007, Cooper et al. [29] reported a highly cross-linked, microporous poly(arylene ethynylene)s network, thus the first microporous polymer network with distinct π-conjugation and introduced the term "conjugated microporous polymer (CMP)" for this class of materials. Since their discovery, CMPs chemistry has intrigued scientists across the globe and been promoted rapidly, resulting in a strong growth in publications over the last decade. For instance, Thomas et al. [30] reported a spirobifluorene-type CMP with stable interface and application potential in organic light emitting diodes Since discovered in 2007, conjugated microporous polymers (CMPs) have been developed for numerous applications including gas adsorption, sensing, organic and photoredox catalysis, energy storage, etc. While featuring abundant micropores, the structural rigidity derived from CMPs' stable π-conjugated skeleton leads to insolubility and thus poor processability, which severely limits their applicability, e.g., in CMP-based devices. Hence, the development of CMPs whose structure can not only be controlled on the micro-but also on the macroscale have...

Soft actuators with integration of ultrasensitivity and capability of simultaneous interaction with multiple stimuli through an entire event ask for a high level of structure complexity, adaptability, and/or multi-responsiveness, which is a great challenge. Here, we develop a porous polycarbene-bearing membrane actuator built up from ionic complexation between a poly(ionic liquid) and trimesic acid (TA). The actuator features two concurrent structure gradients, i.e., an electrostatic complexation (EC) degree and a density distribution of a carbene-NH3 adduct (CNA) along the membrane cross-section. The membrane actuator performs the highest sensitivity among the state-of-the-art soft proton actuators toward acetic acid at 10−6 mol L−1 (M) level in aqueous media. Through competing actuation of the two gradients, it is capable of monitoring an entire process of proton-involved chemical reactions that comprise multiple stimuli and operational steps. The present achievement constitutes a significant step toward real-life application of soft actuators in chemical sensing and reaction technology.

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Conventional polymer additives have a substantial impact on synthetic inorganic chemistry, but critical shortcomings remain; for example, low solubility in organic solvents and potential thermodynamic aggregates. Poly(ionic liquid)s have now been used as efficient additives that enable a high level control of bismuth sulfide crystals with significant size and morphological diversities. The bismuth sulfides exhibit tunable band structure as a result of the quantum size effects. Moreover, poly(ionic liquid)s are able to couple with as-synthesized bismuth sulfides chemically and endow a modified surface electronic structure, which allows resultant products to possess outstanding electrocatalytic performance for water oxidation, although its commercial counterpart is catalytically inert.

the PSCs devices, which is the dominating bottleneck towards commercialization. [3] Even though various strategies, such as dimensionality reduction, [4] chemical compositional engineering, [5] and introduction of insulating polymers, [6] have been developed and exploited to elongate the service time of PSCs, the high performance of PSCs is difficult to retain as the stability improves. [7] Surface passivation as an effective method for high-efficiency and stable PSCs has been widely investigated. [8] A number of materials have been chosen as surface passivators. For instance, the insulating polymer such as polystyrene can serve as a water-resistant layer to protect the perovskite from ambient, although the PCE decreased with the increased tunneling layer thickness due to the reduced electron tunneling rare. [6a] Yang and coauthors showed that theophylline can passivate the defects on the perovskite surface and improve stability of the device under ambient conditions because of the optimal configuration of N-H and CO. [9] In 2021, Bao et al. demonstrated that the energetics of the perovskite surface can be directly transformed from p-to n-type during the defect passivation process by using capsaicin, resulting in the highest efficiency of 21.88% for polycrystalline MAPbI 3 based p-i-n PSCs with outstanding device stability. [10] Moreover, Lewis bases have proven to be remarkable passivators. [11] Lewis bases participate in the passivation by giving electron pairs to Pb 2+ thus neutralizing the positive charge at the surfaces and grain boundaries, which is beneficial to suppress non-radiative interfacial recombination. [12] Furthermore, they can prevent degrading agents in the ambient environment from approaching the surface and endow the perovskite with high stability. [8a,13] Recent experimental studies demonstrated that bidentate ligands with two effective passivation groups exhibit outstanding performance on surface passivation. [14] The strong bonding between the molecules and the surfaces makes it conducive to passivating perovskite defects and preventing the external water from contacting the perovskite. 2-mercaptopyridine (2-MP), a bidentate ligand, which combines pyridine and thiol (SH) groups and has shown good inhibitive performance as a corrosion inhibitor for mild steel and copper. [15] In 2019, 2-MP was first employed by Zhu et al. for the surface Contemporary perovskite solar cells (PSCs) have drawn substantial interest due to their high photovoltaic efficiency. However, the instability of perovskite in a humid environment restricts the service time extension and limits the largescale application of PSCs. Herein, a series of passivation molecules (PMs), 2-MEP, 2-MDEP, 2-MTEP, and 2-MQEP, featuring different lengths of alkyl chains have been designed based on 2-mercaptopyridine (2-MP) which greatly improve the stability of PSCs in the humid environment. First-principles calculations demonstrate that the designed molecules offer stronger adsorption on the perovskite surface compared with 2-...

While hole-doped Mn-based perovskites have been under thorough investigation in the past 10 years, the electron-doped counterparts only received a limited attention and their electronic and magnetic properties are still not fully understood. To obtain a better physical understanding on the origin of their giant magnetoresistances, we have studied in this paper the effect of Ce doping on various magnetic metastable states of LaMnO 3 compounds. The self-consistent calculations were done within the framework of unrestricted Hartree-Fock approximation. A realistic multiband d-p Hamiltonian and a generalized Jahn-Teller coupling Hamiltonian are adopted to describe the systems. The densities of states and stabilities of the various states are analyzed as functions of model parameters. Our results show that the A-type antiferromagnetic insulator of undoped parent LaMnO 3 compound is stabilized by the Jahn-Teller distortion. As Ce doping increases, the ground state of La 1Ϫx Ce x MnO 3 compounds takes consecutively the ferromagnetic state ͑for 0.01Ͻxр0.62), the C-type antiferromagnetic state ͑for 0.62Ͻxр0.88), and the G-type antiferromagnetic state ͑for 0.88Ͻxр1.0), respectively.