General synthesis of hollow mesoporous conducting polymers by dual-colloid interface co-assembly for high-energy-density micro-supercapacitors

Rational design and precise regulation over the morphology, structure, and pore size of functional conducting mesoporous polymers with enriched active sites and shorten electron–ion transport pathway are extremely important for developing high-performance micro-supercapacitors (MSCs), but still remain a great challenge. Herein, a general dual-colloid interface co-assembly strategy is proposed to fabricate hollow mesoporous polypyrrole nano-bowls (mPPy-nbs) for high-energy-density solid-state planar MSCs. By simply adjusting the size of block copolymer micelles, the diameter of polystyrene nanospheres and the amount of pyrrole monomer, mesopore size of the shell, void and shell thickness of mPPy-nbs can be simultaneously controlled. Importantly, this strategy can be further utilized to synthesize other hollow mesoporous polymers, including poly(tris(4-aminophenyl)amine), poly(1,3,5-triaminobenzene) and their copolymers, demonstrative of excellent universality. The structurally optimized mPPy-nb exhibits high specific surface area of 122 m^(2) g^(−1)and large capacitance of 225 F g^(−1) at 1 mV s^(−1). Furthermore, the MSCs assembled by mPPy-nbs deliver impressive volumetric capacitance of 90 F cm^(−3) and energy density of 2.0 mWh cm^(−3), superior to the most reported polymers-based MSCs. Also, the fabricated MSCs present excellent flexibility with almost no capacitance decay under varying bending states, and robust serial/parallel self-integration for boosting voltage and capacitance output. Therefore, this work will inspire the new design of mesoporous conducting polymer materials toward high-performance microscale supercapacitive devices.

Hollow Bio-derived Polymer Nanospheres with Ordered Mesopores for Sodium-Ion Battery

Bio-inspired hierarchical self-assembly provides elegant and powerful bottom-up strategies for the creation of complex materials.However,the current self-assembly approaches for natural bio-compounds often result in materials with limited diversity and complexity in architecture as well as microstructure.Here,we develop a novel coordination polymerization-driven hierarchical assembly of micelle strategy,using phytic acid-based natural compounds as an example,for the spatially controlled fabrication of metal coordination bio-derived polymers.The resultant ferric phytate polymer nanospheres feature hollow architecture,ordered meso-channels of^12 nm,high surface area of 401 m2 g−1,and large pore volume of 0.53 cm3 g−1.As an advanced anode material,this bio-derivative polymer delivers a remarkable reversible capacity of 540 mAh g−1 at 50 mA g−1,good rate capability,and cycling stability for sodium-ion batteries.This study holds great potential of the design of new complex bio-materials with supramolecular chemistry.

Mesoporous polymers:soft-template self-assembly synthesis and applications

Mesoporous polymers combine the advantages of polymer materials(abundant polar functional groups,lightweight,flexibility,and processability)and mesoporous structures(high specific surface area,adjustable pore structure,and large pore volume);hence,they have great application potential in sensing,adsorption,catalysis,energy storage,biomedicine,etc.Currently,developing advanced synthetic strategies for mesoporous polymers and investigating their intrinsic applications have become hot research topics.Soft-template-based self-assembly is regarded as a promising approach for synthesizing mesoporous polymers.This work reviews recent progress in the synthetic strategy for producing various mesoporous polymers using soft-template selfassembly,focusing on the synthesis of conductive polymers,phenol-based polymers,and resin-based polymers and their potential applications.Finally,perspectives on future applications of mesoporous polymers,along with a few challenges that need to be resolved,are also discussed in this review.

Micro-interfaces modulation by UV-ozone substrate treatment for MPEA vapor fluorescence detection

Drug abuse directly endangers human health and social security,hence its sensitive and rapid detection is vitally important.In recent years,organic film-based fluorescent sensing technology has attracted more and more attention in the detection of drugs and explosives due to its advantages of simple operation and rapid detection.For film-based fluorescent sensors,in addition to sensitive materials,the surface morphology of the film is also an important factor affecting the performance.In previous studies,the regulation of surface morphology mainly depends on concentration changes or complex templates.Here,a novel fluorescent polymer probe was designed and synthesized,and a simple and efficient ultraviolet(UV)-ozone substrate treatment method is used to adjust their surface morphology.The results show that film has an excellent fluorescence enhancement effect upon exposure to methylphenethylamine(MPEA,a simulant of methamphetamine)vapor.The sensing effect of the film is significantly improved after UV-ozone substrate treatment,and the limit of detection was decreased by 10.4 times from 2.59 to 0.25 ppm.Further experiments show that the sensing performance of other fluorescent probe can also be improved by the UV-ozone substrate treatment.This convenient and general method may become a very effective approach to improve the performance of film-based fluorescent sensors.

Recent progress in thin film fluorescent probe for organic amine vapour

There are great needs for real-time detection of volatile organic amines(VOA)through low-cost detection methods in public health,food safety,and environmental monitoring area.Organic thin-film fluorescent probe(OTFFP)is expected to become a new and efficient means of detecting VOA because of its fast response,high sensitivity,no contamination to the analyte and ease to prepare a portable instrument.Compared with the mature detection methods in solution,research on solid fluorescence sensing has been less studied.In this article,we review recent progress in OTFFP research for VOA vapour.We mainly focus on the new fluorescent sensing mechanisms applied in solid state in recent years and the design principle of probes for different types of organic amines(such as primary amine,secondary amine,tertiary amine and aromatic amine).We also review the material structures of these probes and the strategies to enhance their sensitivity or selectivity.

Microcrystal induced emission enhancement of a small molecule probe and its use for highly efficient detection of 2,4,6-trinitrophenol in water

In this contribution, we reported a very simple and small molecule material, 2,5-dimethoxyterephthalaldehyde(DMA). It exhibited a relatively weak fluorescence in solution, while showed a steadily increased green fluorescence with typical aggregation-induced enhanced emission(AIE) effect for forming a cubic-like microcrystal structure in THF-H2 O mixed solvent.The microcrystals presented significantly higher fluorescence than that of amorphous aggregates. The DMA microcrystals suspension showed a good response to 2,4,6-trinitrophenol(TNP) with a LOD of 1.2×10^(-7) M, which is the best result of TNP detection in aqueous solution. Quantum chemical calculation revealed that DMA is a donor(D)-receptor(A) type molecule with methoxy unit as donor and carbonyl moiety as receptor. Its emission arises from an intramolecular charge transfer(ICT) from methoxy units to carbonyl units. NMR indicated that there is a strong hydrogen bond interaction between DMA and TNP.Hydrogen bond interaction can effectively decrease the intermolecular distance of DMA and TNP, which will increase the efficiency of photoinduced electron transfer(PET) and fluorescence resonance energy transfer(FRET), and hence will be advantageous for its selectivity. The microcrystal induced enhanced emission could be generally used for kinds of target molecules analysis.

A selective and stepwise aggregation of a new fluorescent probe for dinitrate explosive differentiation by self-adaptive host-guest interaction

Nitrate explosive is hard to detect due to lack of aromatic ring and weak interaction with fluorescence probe.More challenging is even to differentiate the dinitrates with multiple nitrate explosives based on photo induced electron transfer or aggregation caused fluorescence change mechanism.A highly selective dinitrate explosive probe was designed based on a new strategy-stepwise aggregation of multiple anchored fluorene dimer 8Py-2 F.Compared with its monomer counterpart 2Py-F,8Py-2 F showed a selective and stepwise fluorescence quenching to dinitrate explosives-ethylene glycol(EGDN)and triethylene glycol dinitrate(TEGDN).The limits of detection(LODs)are 2.72μM for TEGDN and 0.46μM for EGDN,which is three orders of magnitude lower than those of 2Py-F.The stepwise quenching process is well matched with the stepwise aggregation process as evidence by scanning electron microscopy(SEM).Nuclear magnetic resonance(NMR)and quantum chemical calculation proved the interaction force between the dinitrate and 8Py-2 F is hydron bonding interaction,and interaction distance is far less than that of the multiple nitrates coming from the flexibility of the chain and steric hinderance,which resulted in a self-adaptive interaction and higher selectivity.The new strategy is beneficial for the differentiation of the chemicals with similar energy level which is difficult to realize via other method,and the new method provides fluorometric probe for dinitrate explosive detection and makes it an ideal candidate for chemical detection and analysis in public safety and environmental monitoring.

Two-dimensional mesoporous sensing materials

Two-dimensional mesoporous materials combing ultrathin nanosheet morphology with well-defined mesoporous structures,are now emerging and becoming increasingly important for their promising applications in energy storage,electronic devices,electrocatalysts and so on.Here,we synthesized a kind of polypyrrole-based two-dimensional mesoporous materials with uniform pore size,ultrathin thickness and high surface area.Serving for electrochemical NH3 sensor,they exhibited a fast response and high sensitivity.Therefore,our study would promote much interest in design of new materials for gas sensor applications.

Emerging hierarchical mesoporous materials of covalent organic frameworks

Benefiting from abundant exposed active sites,minimized diffusion resistance of guest molecules,facilitated mass transfer process and enhanced storage capacity,covalent organic frameworks(COFs)have gained widespread scientific attention[1–4].Further construction of mesopores regarding pore engineering(pore size,pore geometry,pore volume,and framework compositions)in COFs can improve mass transport,accessibility as well as size-selectivity of the special guest moieties,thus exhibiting potential in catalysis,energy storage and separation and so on[5,6].