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Fabrics are often used as freestanding substrates for energy storage devices owing to their hierarchical porous structure and excellent mechanical flexibility. However, it is still a challenge to achieve a high loading mass of electroactive materials for outstanding electrochemical performance. In this work, with the help of high swelling property of chitosan, the chitosan-viscose nonwoven fabric (CVF) is successfully reconstructed to expand its specific surface area for flexible conductive substrates in the supercapacitors. Then, multi-walled carbon nanotubes (MWCNTs) are coated on the surface of crosslinked chitosan-viscose nonwoven fabric (c-CVF) to form the conductive framework. Subsequently, polypyrrole (PPy) is deposited by in-situ interfacial polymerization on the above conductive MWCNT/c-CVF substrate. The optimized PPy/MWCNT/c-CVF composite electrode shows not only a high electrical conductivity of 285.9 ± 1.2 S·cm

In this work, a new series of supramolecular discotic liquid crystals induced by hydrogen bonding between triazines T x and aromatic acids A y are presented, most of which exhibit columnar mesomorphic properties. The design strategy of combining the hydrogen bond parallel to the molecular plane with the π-stacking trend of triazine derivatives and aromatic acids was utilized, which has been widely confirmed by nematic, smectic or columnar liquid crystal phases. The formation of hydrogen bonded complexes was proven by FT-IR and 1H NMR spectroscopy and their stability studied by variable temperature FT-IR techniques. All prepared hydrogen bonded complexes displayed mesogenic properties and their liquid crystalline properties were investigated by means of DSC, POM and XRD. This work provides useful information to assist our further design of hydrogen bonded supramolecular liquid crystals for optoelectronic applications.

In this work, a series of carbon dots (CDs) modified hollow g-C3N4 spheres (HCNS-Cx) were constructed via a double in situ approach using cyanamide and glucose as precursors, respectively. As HCNS-Cx was synthesized by one-step in situ thermal polymerization of two precursors, which could make CDs and g-C3N4 keep tight connection and increase the separation of the photogenerated electron-hole pairs. The average diameter and wall thickness of the HCNS-Cx are about 355 nm and 55 nm, respectively. Under the visible light irradiation, the H2 evolution rate (HER) of HCNS-C1.0 (2322 μmol g−1 h−1) was 19 times that of bulk g-C3N4 (122 μmol g−1 h−1) and 1.8 times that of HCNS without CDs modification (1289 μmol g−1 h−1), respectively. And its apparent quantum efficiency is 17.93% at 420 nm. The specific surface area, light absorption capacity, and charge carrier mobility of HCNS-Cx could be dramatically improved due to the introduction of CDs and hollow structures of g-C3N4 spheres, resulting in a significant improvement of photocatalytic activity.

A sustainable and low-cost separator is highly required for electrochemical energy storage systems. Herein, a type of modified natural wood film with excellent mechanical properties, ion conductivity and thermal stability is fabricated for high-performance lithium ion batteries. Using the modified natural wood film as a separator, the fabricated symmetric cell exhibits a more stable and lower plating/stripping voltage for Li than that of the cell with a commercialized polypropylene (PP) separator. The LiFePO

A novel bilayer heterogeneous poly(ionic liquid) electrolyte consisting of a polycation complex and a polyanion complex is designed for highly flexible supercapacitors, which exhibit a high working potential of 3.0 V, energy density of 33 W h kg−1 and a long self-discharge time of 23.2 h.

A self-healing antibacterial hydrogel was fabricated for accelerating infected wound healing. This hydrogel possesses biocompatible, self-healing, antibacterial and antibiotic-free properties, and thus is promising as a wound dressing.

Mechanically compressible energy devices represent one of the most promising candidates for powering flexible and portable electronics, but often suffer from their limited stability of performance under high compressive strains....

The 3D supramolecular framework (3D-SF) is constructed in this work through the hydrogen bond assisted self-assembly of spherical dendritic nanopolymer to regulate the flexibility, stability, and resistive switching (RS) performance of perovskite resistive random-access memory (RRAM). Herein, the 3D-SF network acts as the perovskite crystallization template to regulate the perovskite crystallization process due to its coordination interaction of functional groups with the perovskite grains, presenting the uniform, pinhole-free, and compact perovskite morphology for stable flexible RRAM. The 3D-SF network in situ stays at the perovskite intergranular boundaries to crosslink the perovskite grains. The RS performance of 3D-SF-modified perovskite RRAM device is evidently improved to the ON/OFF ratio of 10

The introduction of polymer additives provides a simple effective method to modify perovskite grain boundaries to improve power conversion efficiency (PCE) and stability of perovskite solar cells (PSCs). In this work, the high-quality methylammonium lead triiodide (MAPbI3) perovskite film is prepared by adding the protonated polyamide-amine dendrimer (NH3+-PAMAM) to the perovskite precursor solution to regulate the crystalline growth process. The cross-linked perovskite grain structure induced by dendritic NH3+-functionalized PAMAM macromolecules results in the formation of compact and pinhole-free perovskite film owing to the suppression of perovskite gain boundaries. Finally, the unsealed NH3+-PAMAM modified PSC device achieves the highest PCE value of 16.03%, representing an increase of 48% compared with the control PSC device. Also, the unencapsulated NH3+-PAMAM-modified PSC device retained 75% of initial PCE value after being exposed to an ambient environment for 20 days, which is obviously higher than 10% for the control device. The improvements of perovskite morphology and photovoltaic performance are attributed to the modification of NH3+-PAMAM dendrimers.

As a novel two-dimensional material, Ti3C2 MXenes has attracted lots of attention in biomedical filed for its large surface area and excellent near-infrared (NIR) responsiveness. In this paper, an in-situ growth and self-assembly approach was employed to combine gold nanorods (GNRs) with Ti3C2 nanosheets to prepare intelligent sandwich-like Ti3C2@GNRs/PDA/Ti3C2 nanohybrids. Compared with Ti3C2 nanosheets, in-situ growth Ti3C2@GNRs possessed excellent photothermal conversion efficiency (45.89%), caused by the distinguished photothermal synergy between GNRs and Ti3C2 nanosheets. Moreover, the high specific surface area of Ti3C2 MXene and outstanding adhesion performance of PDA endowed Ti3C2@GNRs/PDA/Ti3C2 nanohybrids with superior drug loading ability for doxorubicin hydrochloride (DOX) (95.88%). Besides, Ti3C2@GNRs/PDA/Ti3C2 nanohybrids displayed distinct pH/NIR responsive drug release properties upon NIR irradiation owing to the strong π-π stacking interaction between Ti3C2@GNRs/PDA/Ti3C2 and DOX, along with the excellent NIR-responsiveness of Ti3C2@GNRs/PDA/Ti3C2. This paper offers a practicable method to prepare Ti3C2 MXene-based nanoplatform with synergistically enhanced NIR drug release behavior, brilliant biocompatibility and high drug loading efficiency, which is expected to be applied in remote cancer therapy.

The intergranular interface modification of organic-inorganic hybrid perovskites (OHP) is an important issue to regulate the flexibility, stability, and resistive switching (RS) performance of resistive random-access memories (RRAMs). A novel strategy of polymer additives for OHP intergranular interface modification is explored in this work with the polyanionic backbone to improve the distribution of cage-shaped cavity molecules at the perovskite grain boundaries. Specifically speaking, poly(1-adamantylammonium acrylate) (PADAm) is first synthesized through the acid-base reaction of polyacrylic acid with 1-adamantylamine to simultaneously realize the introduction of a cage-shaped cavity molecule and the polyanionic backbone. Herein, organic ammonium cations 1-adamantylammonium (ADNH

Multi-responsive hybrid microgels have attracted lots of attention in biomedical filed owing to the tunable degree of flexibility, high particle stability, and remarkable sensitivity to external stimuli. In this paper, a novel remote drug delivery platform based on gold nanorods (AuNRs)-P(NIPAM-co-AAc) (PNA) hybrid microgel was prepared by electrostatic self-assembly approach. The electrostatic self-assembly of mercapto-modified polyethylene glycol (mPEG) and polyallylamine hydrochloride (PAH) was utilized to safeguard AuNRs, which could greatly enhance the stability of AuNRs and endow AuNRs-PNA hybrid microgels with excellent physiological dispersibility and stability. More importantly, due to the change of electrostatic force between microgels and DOX at different pH values, as well as the thermal sensitivity of PNA and NIR response of AuNRs, AuNR-PNA hybrid microgels displayed prominently pH/temperature/NIR synergistic responsive drug release performance. This paper furnishes a green and feasible method to prepare intelligently remotely controllable hybrid microgels with great physiological stability, which has great perspectives in photothermal therapy and remotely controllable drug delivery area. pH/temperature/NIR synergistic responsive AuNRs-P(NIPAM-co-AAc) hybrid microgel for smart drug delivery was prepared by in situ self-assembly.

Photodynamic therapy (PDT) as an antibiotic-free method could effectively solve the bacterial infection problem and avoid the emergence of multi-drug resistant (MDR) bacteria. In this paper, Ti3C2@gold nanorods (GNRs)/PDA nanoparticles with synergistic photodynamic antibacterial properties were obtained by coating PDA on the surface of in-situ growth Ti3C2@GNRs. GNRs growing on the surface of Ti3C2 MXene nanosheets effectively prevented the aggregation of Ti3C2 nanosheets, which ensured the distinct photodynamic antibacterial performance of Ti3C2. In addition, the introduction of SH-PEG-CH3 to Ti3C2@GNRs nanosheets endowed Ti3C2@GNRs/PDA nanoparticles with good biocompatibility. Furthermore, Ti3C2@GNRs/PDA nanoparticles possessed synergistically enhanced photodynamic properties, caused by the remarkable photodynamic properties of Ti3C2 MXene and PDA. In addition, with the increase of PDA content, Ti3C2@GNRs/PDA nanoparticles could produce more 1O2 under 660 nm laser irradiation and the minimum inhibitory concentrations (MIC) of Ti3C2@GNRs/PDA50 nanoparticles against E. coli and S. aureus decreased to about 0.07 mg/mL. Thus, this work utilizes the 1O2-generating performance of Ti3C2 MXene and PDA to fabricate Ti3C2@GNRs/PDA nanoparticles with synergistically enhanced photodynamic antibacterial activities, which is expected to be applied in antibiotic-free antibacterial field.

The CuSCN-containing perovskite solar cells (PSCs) are presently of great research focus due to the high carrier mobility and well-aligned work function of the CuSCN hole-transporting layer. The improvement of photovoltaic performance and stability is still an important subject in the practical applications of CuSCN-containing PSCs. Herein, a facile approach to improve the efficiency and stability of CuSCN-containing PSCs is developed by spin-coating the triphenylamine-based macromolecules between the CuSCN hole-transporting layer and metallic electrode, such as linear macromolecule poly-TPD and branched macromolecule CRA-TPA. The maximum power conversion efficiency (PCE) of CuSCN-containing PSCs is increased by linear triphenylamine-based macromolecule poly-TPD to 10.36% while the PCE value of CuSCN-containing PSCs, being modified by branched triphenylamine-based macromolecule CRA-TPA, reaches up to 11.97%. Evidently, the PCE values are nearly two times higher than 5.95% of CuSCN-containing control device. The photovoltaic improvement of macromolecule-modified CuSCN-containing PSCs is mainly caused by the strong hole-transporting capacity of triphenylamine-based macromolecules inducing the reduction of charge recombination, which is derived from the reduced potential barrier of hole transportation including the flatness and coverage improvement in the triphenylamine-based macromolecular functional layer. In addition, the stability of macromolecule-modified CuSCN-containing PSCs is significantly improved due to the protection of triphenylamine-based macromolecular layer on the perovskite film, so that the unencapsulated macromolecule-modified CuSCN-containing PSC device can keep over 70–80% of initial PCE value after 20-day exposure under ambient environment (relative humidity (RH) = 50%, 25°C). This work provides a facile approach to enhance the efficiency and stability of CuSCN-containing PSCs through the modification of triphenylamine-based macromolecules between the CuSCN hole-transporting layer and metallic electrode.

In recent years, low-cost wearable energy storage devices attract much more attention. In this work, the PET/CuS/PPy composite electrodes are fabricated for portable flexible solid-state supercapac...

Both perovskites and organic semiconductors are promising candidates for next-generation portable and wearable photodetectors (PDs), owing to their facile solution processibility and remarkable optoelectronic features. In recent years, there has been growing interest in combining the two and constructing perovskite/organic hybrid PDs, which are demonstrated to present a broad photoresponse spectrum, high photoresponsivity and good environmental stability. Since great progress has already been made, a comprehensive summary would be very important for this field. However, this is still lacking. In this review, we provide a thorough progress report and in-depth discussion on the perovskite/organic hybrid PDs, from the very fundamental device operation principles to advanced design strategies. Firstly, the main parameters of the PD devices are introduced. Then, the developments of the perovskite/organic hybrid PDs, including photodiodes, photoconductors and phototransistors, are discussed in detail. Finally, current challenges are summarized and potential solutions are proposed.

Random resistive access memory (RRAM) devices with a simple structure, low power consumption, and tunable switching behavior have emerged as promising candidates to simulate biological synapses. Here, we demonstrate solution-processable RRAM devices with FeC–rGO nanocomposites by intercalating nano-aggregating ferrocenes (FeCs) between the reduced graphene oxide (rGO) sheets, in which FeCs anchor on the surface of rGO through π–π stacking interactions. The Al/FeC–rGO/ITO devices fabricated by spin-coating exhibit a low SET/RESET voltage of −1.7 V/+2.1 V and a high ON/OFF ratio of 108, which results from the formation/rupture of conductive paths between rGO sheets gated by the redox of FeCs. Besides, the devices show high repeatability, excellent durability and favorable flexibility. In addition, the obtained device can be utilized to simulate the potentiation and depression of synapses by applying a pulse voltage below VSET, further contributing to image pattern recognition. Thus, this approach aims to fabricate information storage devices for future use in artificial intelligence.

Flexible supercapacitors have attracted increasing interest due to their high power density, long-term cycling life and excellent safety. Like other energy storage devices, flexible supercapacitors exhibit serious performance degradation as they work in extremely cold and/or sweltering climates, which greatly limit their practical applications. Here, we demonstrate a polymer hydrogel with high ionic conductivity for flexible supercapacitors with high performance and excellent climate tolerance. The wide temperature adaptability of the polymer hydrogel is enabled by introducing an additive of dimethyl sulfoxide, which can form abundant hydrogen bonds with water molecules and functional groups of polymer molecules. The optimized hydrogel exhibits high ionic conductivities of 0.82 and 1.12 S m−1 at −20 and 100 °C, respectively, comparable with that at room temperature. Using the polymer hydrogel as an electrolyte, the resulting supercapacitors not only show high electrochemical performance, but also exhibit high capacitance retention up to 91% and 85% at both low (−20 °C) and high (100 °C) temperatures, compared with that at room temperature. In addition, the developed supercapacitors possess excellent mechanical flexibility even at −20 °C. Polymer hydrogels with wide temperature tolerance could be easily functionalized and broadly used for other flexible energy devices and electronics working in harsh environments in the future.

A monolithic supercapacitor electrode of a KNi0.67Co0.33PO4·H2O-graphene composite hydrogel supported on Ni foam (KNCP-GH/NF) is first prepared by a one-step hydrothermal method, which achieves notable improvements in the electrode surface area and mass-loading of active materials. The KNCP-GH/NF electrode enjoys a hierarchical open-porous structure, where the KNCP-GH composite hydrogel fills in the voids in NF and the porous graphene hydrogel (GH) simultaneously provides a large support surface for growing active KNCP nanoflowers. Accordingly, the KNCP-GH/NF electrode exhibits a strikingly high capacity of 3240 mC cm−2 (876 C g−1) at 2 mA cm−2 and a satisfactory rate performance with 78.3% retention at 100 mA cm−2. Further, an all-solid-state asymmetric supercapacitor, constituted by using KNCP-GH/NF and Fe2P/GH/NF as the cathode and anode, respectively, and PVA-KOH as the solid-state gel electrolyte, delivers a high energy density of 69.2 W h kg−1 (3.9 mW h cm−3) and a power density of 13 229 W kg−1 (720 mW h cm−3) as well as notable cyclability with 81.2% capacity retention after 10 000 charge/discharge cycles. These attractive performances suggest a promising potential for a hierarchically structured KNCP-GH/NF electrode for the high-performance energy storage application.

Dental plaque biofilms are believed to be one of the principal virulence factors in periodontitis resulting in tooth loss. Traditional mouthwashes are limited due to the continuous flow of saliva and poor drug penetration ability in the biofilm. Herein, we fabricated an antibiotic delivery platform based on natural polysaccharides (chitosan and cyclodextrin) as a novel mouthwash for the topical cavity delivery of minocycline. The penetration and residence mechanisms demonstrate that the platform can prolong the residence time up to 12 h on biofilms. Furthermore, sustained release can enhance the penetration of drugs into biofilms. In vitro antibiofilm experimental results indicated that the mouthwash effectively kills bacteria and eradicate biofilms. Effective treatment in vivo was confirmed by the significantly reduced dental plaque and alleviated inflammation observed in a rat periodontitis model. In summary, this novel platform can improve antibiofilm efficiency and prevent drugs from being washed away by saliva, which may provide benefits for many oral infectious diseases.

Remotely multi-responsive chitosan (CS) hydrogels holds great promise in the design of anticancer drug carriers. In this paper, near-infrared (NIR)-/pH-dual responsive CS/β-GP/Ti

The stability of perovskite thin films is one of the most critical challenges for their practical application in photovoltaic devices. The defects of hybrid organic–inorganic perovskites, such as t...

Highlights Poly(propylene glycol) bis(2-aminopropyl ether) (PEA) additive is introduced into the perovskite solar cells to passivate both surface and grain boundary defects, and hence improve the device efficiency and stability. MAPbI3 device with PEA exhibits significantly enhanced efficiency of 18.87%. (FAPbI3)1-x(MAPbBr3)x device with PEA exhibits enhanced efficiency of 21.60%. The unsealed passivated device degrades only by 5% in PCE after being exposed to air (30 ± 5% relative humidity) for 30 days. Electronic supplementary material The online version of this article (10.1007/s40820-020-00517-y) contains supplementary material, which is available to authorized users., Perovskite solar cells (PSCs) are regarded as promising candidates for future renewable energy production. High-density defects in the perovskite films, however, lead to unsatisfactory device performances. Here, poly(propylene glycol) bis(2-aminopropyl ether) (PEA) additive is utilized to passivate the trap states in perovskite. The PEA molecules chemically interact with lead ions in perovskite, considerably passivate surface and bulk defects, which is in favor of charge transfer and extraction. Furthermore, the PEA additive can efficiently block moisture and oxygen to prolong the device lifetime. As a result, PEA-treated MAPbI3 (MA: CH3NH3) solar cells show increased power conversion efficiency (PCE) (from 17.18 to 18.87%) and good long-term stability. When PEA is introduced to (FAPbI3)1-x(MAPbBr3)x (FA: HC(NH2)2) solar cells, the PCE is enhanced from 19.66 to 21.60%. For both perovskites, their severe device hysteresis is efficiently relieved by PEA. Electronic supplementary material The online version of this article (10.1007/s40820-020-00517-y) contains supplementary material, which is available to authorized users.

In this paper, a novel one-pot strategy was utilized to immobilize gold nanorods (GNRs) onto the surface of PEGylated graphene oxide (GO-PEG) via polydopamine (PDA) to fabricate GNRs/GO@PDA hybrid nanosheets. The GNRs/GO@PDA nanosheets possessed excellent photostability and photothermal conversion efficiency (36.10%), due to the robust interfacial immobilization of PDA between GNRs and GO-PEG. Besides, GNRs/GO@PDA also could be utilized to be an efficient drug nano-vehicle that possessed an excellent loading ability for anticancer drug doxorubicin hydrochloride (DOX) (86.16%). Furthermore, the drug release of hybrid nanosheets could be triggered by pH value and near-infrared (NIR) light irradiation, which could be mainly ascribed to the strong π–π stacking interaction between GNRs/GO@PDA and DOX, as well as the brilliant NIR-responsive property of GNRs/GO@PDA. It was found that GNRs/GO@PDA possessed extremely low cytotoxicity to MCF-7 cells even at 250 μg mL−1, while GNRs/GO@PDA(DOX) showed obvious cytotoxicity at 100 μg mL−1. Thus, this paper presents a feasible strategy to fabricate GNRs/GO hybrid nanosheets with high drug loading capacity, excellent photothermal conversion property and pH/NIR-stimuli-responsive drug delivery performance, which possesses brilliant potentials to be an efficient platform for remotely triggered drug delivery.

In the present paper, hollow hydroxyapatite/polydopamine/gold nanorods (H-HAP/PDA/AuNRs) hybrid microcapsules was prepared for multi-responsive drug delivery via self-assembly method. PDA/AuNRs hybrid shell was employed to obstruct the initial burst drug release and endow the hybrid vehicle with superior photothermal conversion capacity, robust photothermal stability and brilliant near-infrared (NIR)-responsive delivery property. Moreover, due to the mesoporous structure of H-HAP as well as the strong mutual adsorption between PDA and drug, H-HAP/PDA/AuNRs exhibited excellent drug loading efficiency (95.6%). The drug release results demonstrated that the hybrid vehicle possessed distinct pH-/NIR- dual responsiveness, which due to the disintegration of HAP/PDA matrix in acid condition and the synergistically enhanced NIR responsiveness of PDA/AuNRs. Furthermore, cell viability results demonstrated that H-HAP/PDA/AuNRs exhibited outstanding biocompatibility and low bio-toxicity. Thus, the as-prepared H-HAP/PDA/AuNRs hybrid microcapsules hold great promise as novel smart drug carriers for remotely controllable drug delivery.

A carbon-coated g-C3N4 nanotube (C-TCN) was constructed via the concurrent thermal polymerization of urea and carbonization of glucose. When the mass ratio of glucose to urea was 1/30, after the pr...

Nonradiative recombination energy loss (ΔE3) plays a key role in enhancing device efficiencies for polymer solar cells (PSCs). Until now, there is no clear resolution for reducing ΔE3 via molecular...

“C2N”-species have emerged as a promising material with carbon-like applications in sorption, gas separation and energy storage, while with much higher polarity and functionality. Controlled synthesis of “C2N” structure is still based on complex and less-sustainable monomers, which prohibits its broader industrial application. Here we report a class of well-defined C2(NxOySz)1 carbons with both high content of N/O/S heteroatoms and large specific surface area of up to 1704 m2 g−1, which can be efficiently synthesized through a simple additive condensation process using simple gallic acid and thiourea as the building blocks, without sub-tractive activation. This 1,4-para tri-doped C2(NxOySz)1 structure leads to sufficient CO2 adsorption capacity (3.0 mmol g−1 at 273 K, 1 bar) and a high CO2/N2 selectivity (47.5 for a 0.15/0.85 CO2/N2 mixture at 273 K). Related to the polarity, the polar frameworks can be used as supercapacitor electrodes, with record specific capacitances as high as 255 F g−1at 3.5 V for a symmetric supercapacitor in ionic liquid electrolyte. This work discloses a general way for preparing a novel family of multifunctional, high heteroatom-doped porous materials for various applications.

Recyclable low-temperature phase change microcapsules (LTPCMs) have the potential applications in the short-distance cold chain transportation due to their reliable reusability in cold storage. Herein, LTPCMs are synthesized via in-situ suspension copolymerization of styrene and methyl methacrylate in absence of harm substances, providing the non-crosslinking copolymer shells. n-Dodecane, n-tridecane and n-tetradecane, inducing the microphase separation of non-crosslinking copolymers, are successfully encapsulated to achieve n-do-LTPCMs, n-tri-LTPCMs and n-tetra-LTPCMs, which respectively bear the high phase change enthalpy of 110.53 J·g−1 at −8.69 °C, 38.33 J·g−1/93.71 J·g−1 at −17.61 °C/−4.96 °C and 166.79 J·g−1 at 8.59 °C and subsequently show the cold-discharging periods of 30 min, 40 min and 120 min. The multiple circulation of cold-discharging process indicates the excellent recyclability for cold storage owing to their unchanged cold-discharging period. Especially, n-tetra-LTPCM-65 bears the best comprehensive cold-storing performance in all the previously reported LTPCMs, such as narrow cold-discharging temperature range of 3–4 °C, long cold-discharging period of 69–120 min and low cold-discharging capacity of 33.4 J·g−1·K−1. This work successfully provided the recyclable LTPCMs for cold storage in the short-distance cold chain transportation.

Porous carbon/nitrogen frameworks are an emerging class of noble organic materials with a wide range of potential applications. However, the design and controlled synthesis of those materials are still a challenge. Herein, we present the rational design of such a system with high microporosity, specific surface areas of up to 946 m2 g–1, and excellent condensation yields. The obtained noble frameworks were used for the delivery of larger organic molecules and changed the melting behavior of some daily drug molecules along their highly polarizable surfaces.

It is always challenging to fabricate two-dimensional transition-metal dichalcogenides into multiple hollow micro-/nanostructures with improved properties for various potential applications. Here, hierarchically porous MoS2-C hollow rhomboids (MCHRs) have been creatively synthesized via a facile self-templated solvothermal approach. It has been clarified that the obtained MCHRs assembled beneath ultrathin γ-MnS and carbon cohybridized MoS2 nanosheets under the structural direction of the MnMoO4·0.49H2O self-template. The prepared MCHR anode of sodium-ion batteries exhibited a reversible capacity of 506 mA h g-1 at 0.1 A g-1, ultrahigh rate capabilities up to 10 A g-1 with 310 mA h g-1, and exceptional stability over 3000 cycles. This study provides inspiration for the rational design of hierarchically porous hollow nanostructures with specific geometries as an excellent electrode material for outstanding performance energy storage equipment.

A series of halogenated aminobenzonitrile modified graphitic carbon nitride (g-C3N4) was prepared by a one-step calcination of dicyandiamide and 2-amino-5-halogen-benzonitriles (X-ABN, X = F, Cl, Br or I, 1.67 wt% of dicyandiamide) together, and named as X-ABN-CN. The resulting X-ABN-CN photocatalysts were characterized by X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, ultraviolet–visible diffuse reflection spectroscopy, and photoluminescence spectroscopy. The characterization results indicated that X-ABN-CN have been successfully prepared, and the π-conjugated system and electronic structure of X-ABN-CN could be improved via copolymerization, Ullmann reaction and in situ halogen doping. Under visible light irradiation (λ > 400 nm), the photocatalytic activity of X-ABN-CN were much higher than that of pure g-C3N4 and increase with the increase of halogen atomic number. The hydrogen evolution rate of I-ABN-CN (131.4 μmol h−1) was 7.4 times that of g-C3N4 (17.7 μmol h−1). Furthermore, the corresponding mesoporous X-ABN-CN (X-ABN-MCN, X = F, Cl, Br or I) were prepared by using SiO2 nanoparticles as template. As expected, I-ABN-MCN showed the highest photocatalytic activity in all mesoporous samples, which is about 8.8 times that of g-C3N4. The results manifest that the copolymerization, Ullmann reaction, in situ halogen doping and mesoporous structure could be integrated together to modify g-C3N4 by a simple one-step calcination process.