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Given the breadth of currently arising opportunities and concerns associated with nanoparticles for biomedical imaging, various types of nanoparticles have been widely exploited, especially for cellular/subcellular level probing. However, most currently reported nanoparticles either have inefficient delivery into cells or lack specificity for intracellular destinations. The absence of well-defined nanoplatforms remains a critical challenge hindering practical nano-based bio-imaging. Herein, the authors elaborate on a tailorable membrane-penetrating nanoplatform as a carrier with encapsulated actives and decorated surfaces to tackle the above-mentioned issues. The tunable contents in such a versatile nanoplatform offer huge flexibility to reach the expected properties and functions. Aggregation-induced emission luminogen (AIEgen) is applied to achieve sought-after photophysical properties, specific targeting moieties are installed to give high affinity towards different desired organelles, and critical grafting of cell-penetrating cyclic disulfides (CPCDs) to promote cellular uptake efficiency without sacrificing the specificity. Hereafter, to validate its practicability, the tailored nano products are successfully applied to track the dynamic correlation between mitochondria and lysosomes during autophagy. The authors believe that the strategy and described materials can facilitate the development of functional nanomaterials for various life science applications. Funding Agencies|STINT Joint China-Sweden Mobility Project [CH2017-7243]; Swedish Research Council (VR)Swedish Research Council [VR 2019-02409, 2020-05437]; China Scholarship Council (CSC)China Scholarship Council; Science and Technology Development Fund, Macau SAR [019/2017/AMJ, 0114/2019/A2]; Carl Tryggers Stiftelse [CTS 19:379]; Swedish Government strategic faculty grant in material science (SFO, MATLIU) in Advanced Functional Materials (AFM) (VR) [Dnr. 5.1-2015-5959]; Centre in Nano Science and technology at LiTH (CeNano); LiU Cancer network at Linkoping University

Restricted by the energy gap rule, near-infrared (NIR) luminescent materials face great challenges. Here, we report a newly designed and synthesized organic molecule, 5,5′-([1,2,5]thiadiazolo[3,4-c...

Solar energy, although it has the highest power density available in terms of renewable energy, has the drawback of being erratic. Integrating an energy harvesting and storage device into photovoltaic energy storage modules is a viable route for obtaining self-powered energy systems. Herein, an MXene-based all-solution processed semitransparent flexible photovoltaic supercapacitor (PSC) was fabricated by integrating a flexible organic photovoltaic (OPV) with Ti3C2Tx MXene as the electrode and transparent MXene supercapacitors with an organic ionogel as the electrolyte in the vertical direction, using Ti3C2Tx thin film as a common electrode. In the quest for a semitransparent flexible PSC, Ti3C2Tx MXene was first used as a transparent electrode for OPV with a high power conversion efficiency of 13.6%. The ionogel electrolyte-based transparent MXene supercapacitor shows a high volumetric capacitance of 502 F cm(-3) and excellent stability. Finally, a flexible PSC with a high average transmittance of over 33.5% was successfully constructed by all-solution processing and a remarkable storage efficiency of 88% was achieved. This strategy enables a simple route for fabricating MXene based high-performance all-solution-processed flexible PSCs, which is important for realizing flexible and printable electronics for future technologies. Funding Agencies|Swedish Energy AgencySwedish Energy Agency [EM 42033-1]; Swedish Government Strategic Research Area in Material Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [200900971]; Swedish Research CouncilSwedish Research Council [2017-04123]; SSF Research Infrastructure Fellow Program [RIF 14-0074]; SSF Synergy Program [EM16-0004]; Knut and Alice Wallenberg (KAW) FoundationKnut & Alice Wallenberg Foundation [KAW 2015.0043]; National Natural Science Foundation of ChinaNational Natural Science Foundation of China [61774077]; Open Fund of the State Key Laboratory of Luminescent Materials and Devices [2018-skllmd-12]; Fundamental Research Funds for the Central UniversitiesFundamental Research Funds for the Central Universities

A redox active polymer network film containing donor–node–acceptor (D–n–A) units was prepared by using the electropolymerization (EP) of the precursor (4Cz–4Cl–PBI). The polymer film was characterized by the UV–vis absorption, FT-IR, SEM, XRD and electrochemical techniques. The precursor contains phenyl connected two carbazoles (D) linked by the two sp3 N-nodes on both sides of a tetrachloro-substituted PBI (A). The two N-nodes block the conjugation between D and A units, resulting in an independent redox activity (from D and A) and doping behaviors. This novel concept of the D–n–A polymer effectively increases the conductivity and stability of the n-doped state. The EP film can be prepared on ITO and flexible electrodes with large area, smooth surface morphology, controllable thickness, and nanoporous structure. Notably, the polymer network film showed ambipolar doping characteristics, with high capacitance (both n- and p-doped states). These properties are very suitable to construct ambipolar electrodes...

Pyridal[2,1,3]thiadiazole (PT) is an analogue of benzo[1,2,5]thiadiazole (BT), which is a common acceptor in charge transfer (CT) chromophores. Compared with BT, PT is more electron-deficient and less sterically hindered. Herein we demonstrate the effect of using PT as proto-acceptor in the design of D–A type NIR emitting materials. The compound p-TPA-PT-CN was synthesized, which combines PT with the donor triphenylamine (TPA) and cyano-substituent (CN), and shows NIR emission at ∼700 nm with a high PL efficiency of 0.3 in both solution and solid state. The strong D–A interaction within p-TPA-PT-CN results in a low energy charge-transfer state. The pyridine nitrogen of PT reduces the steric hindrance between PT and the adjacent TPA donor segment, resulting in increased planarity and strong mixing (hybridization) of CT and π–π states (HLCT). Such strong mixing contributes towards a higher luminous efficiency. The OLEDs fabricated with p-TPA-PT-CN as the emitting layer exhibited an EQE of 1.47% and Lmax = 640 cd m−2, which are amongst the highest values reported for NIR-OLED devices.

The twist angle and rotation freedom between the donor (D) and acceptor (A) in D–A materials plays an important role in their photophysical properties. Here, the authors select the asymmetric acceptor pyridal[2,1,3]thiadiazole (PT) to construct two D–A isomers (p-TPA-PT and d-TPA-PT) with different twist angle and rotation freedom due to the donor triphenylamine (TPA) proximal or distal to N-atom (pyridyl), as well as a symmetric bis-triphenylamine-substituted compound DTPA-PT for their investigation. On the basis of experimental and theoretical analysis, the authors have explained how the difference in twist-angle and freedom of rotation affects the photophysical properties of these materials. The p-TPA-PT has small twist angles with a relative large kr, however, the more freedom of rotation of the D–A bond causes larger knr, which is comparable to the kr, and thus a lower photoluminescence (PL) efficiency is obtained in the doped film. Although the d-TPA-PT has relative large twist angles with low kr, the suppressed rotation of the DA bond significantly reduces knr, resulting in more competitive kr when compared with the p-TPA-PT, consequently relatively higher PL efficiency is observed. The DTPA-PT, combination of p-TPA-PT and d-TPA-PT, shows highest kr, much larger than its knr, therefore shows highest PL efficiency. As a result, the DTPA-PT based organic light emitting diode (OLED) shows beautiful deep-red emission, maximum external quantum efficiency of 3.87%, Lmax = 12 000 cd m−2, which is among the best deep-red OLED devices.

Different compared to optoelectronics based on electron transformation, ion transport plays important roles in electrochromic applications. To improve ion transport properties, a novel poly(3,4-dioxythiophene) dimer (PM-BTE) was electropolymerized by an alkoxyl connected 3,4-dioxythiophene dimer and fully characterized. The PM-BTE soft nano-networks exhibit excellent electrochromic properties, which show reversible oxidization and reduction accompanied from dark blue to brown yellow, have an optical contrast ΔT = 38.8%, coloration efficiencies of 263.5 cm2 C−1 at 900 nm, low switching voltages and a response of time 1.8 s, with excellent stability and colour persistence. The electrochromic performance is well promoted compared with that of PEDOT (one-fold in coloration efficiency and 60% in response time for the best), which was found to be a result of the as formed PM-BTE films showing a soft nano-network and providing a compatible ion transport channel.