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The kidneys critically contribute to body homeostasis under the control of the autonomic nerves, which enter the kidney along the renal vasculature. Although the renal sympathetic and sensory nerves have long been confirmed, no significant anatomic evidence exists for renal parasympathetic innervation.We identified cholinergic nerve varicosities associated with the renal vasculature and pelvis using various anatomic research methods, including a genetically modified mouse model and immunostaining. Single-cell RNA sequencing (scRNA-Seq) was used to analyze the expression ofWe found that cholinergic axons supply the main renal artery, segmental renal artery, and renal pelvis. On the renal artery, the newly discovered cholinergic nerve fibers are separated not only from the sympathetic nerves but also from the sensory nerves. We also found cholinergic ganglion cells within the renal nerve plexus. Moreover, the scRNA-Seq analysis suggested that acetylcholine receptors (AChRs) are expressed in the renal artery and its segmental branches. In addition, retrograde tracing suggested vagus afferents conduct the renal sensory pathway to the nucleus of the solitary tract (NTS), and vagus efferents project to the kidney.Cholinergic nerves supply renal vasculature and renal pelvis, and a vagal brain-kidney axis is involved in renal innervation.

Due to the dominant position of deep learning (mostly deep neural networks) in various artificial intelligence applications, recently, ensemble learning based on deep neural networks (ensemble deep learning) has shown significant performances in improving the generalization of learning system. However, since modern deep neural networks usually have millions to billions of parameters, the time and space overheads for training multiple base deep learners and testing with the ensemble deep learner are far greater than that of traditional ensemble learning. Though several algorithms of fast ensemble deep learning have been proposed to promote the deployment of ensemble deep learning in some applications, further advances still need to be made for many applications in specific fields, where the developing time and computing resources are usually restricted or the data to be processed is of large dimensionality. An urgent problem needs to be solved is how to take the significant advantages of ensemble deep learning while reduce the required expenses so that many more applications in specific fields can benefit from it. For the alleviation of this problem, it is essential to know about how ensemble learning has developed under the era of deep learning. Thus, in this article, we present fundamental discussions focusing on data analyses of published works, methodologies, recent advances and unattainability of traditional ensemble learning and ensemble deep learning. We hope this article will be helpful to realize the intrinsic problems and technical challenges faced by future developments of ensemble learning under the era of deep learning., Comment: 47 pages, 8 figures, 15 tables

Hollow carbon spheres (HCS) manifest specific merit in achieving large interior void space, high permeability, wide contactable area, and strong stacking ability with negligible aggregation and have attracted attention due to their high supercapacitor activity. As the key factor affecting supercapacitor performance, the surface chemical properties, shell thickness, roughness, and pore volumes of HCS are the focus of research in this field. Herein, the surface chemical properties and structures of HCS are simultaneously adjusted by a feasible and simple process of in situ activation during assembly of resin and potassium chloride (KCl). This strategy involves KCl participating in resin polymerization and the superior performance of potassium species on activating carbon. The surface N/O content, thickness, defects, and roughness degree of HCS can be controlled by adjusting the dosage of KCl. Electrochemical tests show that optimized HCS has suitable roughness, high surface area, and abundant surface N/O functional groups, which endow it with excellent electrochemical capacitance properties, showing its high potential in supercapacitors.

Expansion microscopy allows super resolution imaging of cellular structures by fluorescence microscopy. However, current protocols achieving large expansion factors (near 8 and beyond), are only applicable to cultured cells and thin tissue slices, but not to bulk tissue in general. Here, we present a method that allows unlimited cycles of expansion of bulk tissue with high isotropy, which we term as Cyc-ExM. The protocol uses identical gel recipe and denaturation reagents in each expansion cycle, which provides ease to the procedure. Cyc-ExM expands biological tissues ~9 fold in each dimension from 7 cycles of expansion and 17-27 fold from 10 cycles. The covalent staining procedure was also optimized to reveal ultrastructural features. Besides, Cyc-ExM is compatible with antibody labeling and multi-scale 3D imaging. Despite volume dilution of signal during expansion, we developed a signal amplification method achieving 8-fold increase in signal, which greatly facilitates the resolution of sub-organelle structures within various tissues.

Heteroatom doping in carbonaceous materials is an effective way to improve the performance of supercapacitors. Herein, the N/B-co-doped ordered mesoporous carbon spheres (N/B-OMC) were developed by a facile ionothermal strategy. The ordered mesoporous phenol/formaldehyde resin (PF) spheres were employed as carbon precursor, which was treated by ionothermal process using 1-butyl 3-methyl-imidazole tetrafronoroborate ([Bmim]BF4) as medium. The [Bmim]BF4 can be absorbed in the pores of PF spheres, leading to N/B-co-doping for the obtained carbon framework without damage in spherical morphology and ordered mesoporous structure. As a result, the dual-heteroatom doping, high surface area and enlarged mesopore size of N/B-OMC can enhance the electrochemical performance, exhibiting its promising as novel electrode materials.

Herein, macroporous carbon sheets (MCS) was synthesized by a re-assembly engineering. In this process, surfactant is combined with oligomeric resin to form micelles, which are re-assembled on the pre-prepared hybrid sheet through hydrogen bonding and electrostatic action, resulting in the reconstruction of relatively regular macropores on the sheet. The obtained MCS maintains the morphology of nanosheet with obvious circular macropores, high specific surface area and pore volume, which improves the charge transfer efficiency and is favorable electrochemical energy storage. As the electrode material for a supercapacitor, the MCS exhibits a high specific capacitance, excellent rate performance and long-term stability, which make the MCS an ideal electrode material for electrochemical energy storage.

In this present work, N-doped carbon nanobelts (N-CNBs) were prepared by a confined-pyrolysis approach and the N-CNBs were derived from a polypyrrole (Ppy) tube coated with a compact silica layer. The silica layer provided a confined space for the Ppy pyrolysis, thereby hindering the rapid overflow of pyrolysis gas, which is the activator for the formation of carbonaceous materials. At the same time, the confined environment can activate the carbon shell to create a thin wall and strip the carbon tube into belt morphology. This process of confined pyrolysis realizes self-activation during the pyrolysis of Ppy to obtain the carbon nanobelts without adding any additional activator, which reduces pollution and preparation cost. In addition, this approach is simple to operate and avoids the disadvantages of other methods that consume time and materials. The as-prepared N-CNB shows cross-linked nanobelt morphology and a rich porous structure with a large specific surface area. As supercapacitor electrode materials, the N-CNB can present abundant active sites, and exhibits a specific capacitance of 246 F · g−1, and excellent ability with 95.44% retention after 10000 cycles. This indicates that the N-CNB is an ideal candidate as a supercapacitor electrode material.

The poor intrinsic mechanical properties of chitosan hydrogels have greatly hindered their practical applications. Inspired by nature, we proposed a strategy to enhance the mechanical properties of chitosan hydrogels by construction of a nanofibrous and cellular architecture in the hydrogel without toxic chemical crosslinking. To this end, electrospun nanofibers including cellulose acetate, polyacrylonitrile, and SiO2 nanofibers were introduced into chitosan hydrogels by homogenous dispersion and lyophilization. With the addition of 30% cellulose acetate nanofibers, the cellular structure could be maintained even in water without crosslinking, and integration of 60% of the nanofibers could guarantee the free-standing structure of the chitosan hydrogel with a low solid content of 1%. Moreover, the SiO2 nanofiber-reinforced chitosan (SiO2 NF/CS) three-dimensional (3D) matrices exhibit complete shape recovery from 80% compressive strain and excellent injectability. The cellular architecture and nanofibrous structure in the SiO2 NF/CS matrices are beneficial for human mesenchymal stem cell adhesion and stretching. Furthermore, the SiO2 NF/CS matrices can also act as powerful vehicles for drug delivery. As an example, bone morphogenetic protein 2 could be immobilized on SiO2 NF/CS matrices to induce osteogenic differentiation. Together, the electrospun nanofiber-reinforced 3D chitosan matrices exhibited improved mechanical properties and enhanced biofunctionality, showing great potential in tissue engineering.

Multi-model ensemble is an important fundamental technique of practical value for many artificial intelligence applications. However, the usage for multi-model ensemble has been limited when it is combined with deep neural networks to construct ensemble of deep neural networks. Due to the big time and computing resources required to train and to integrate multiple deep neural networks for the achievement of multi-model ensemble, the engineering application field where developing time and computing resources are usually restricted, has not yet widespreadly benefited from ensemble of deep neural networks. To alleviate this situation, we present a new multi-model ensemble approach entitled feature transferring based multi-model ensemble (FTBME), for ensemble of deep neural networks. Primarily, we propose a feature transferring based multi-model training strategy to more affordably find multiple extra models based on a given previously optimized deep neural network model. Sequentially, to develop better ensemble solutions, we design a more effective random greedy based ensemble selection strategy to filter out models non-positive to ensemble generalization. Finally, inspired by the idea of averaging parameter points, we propose to fuse the obtained models in weight space which eventually reduces the expense of ensemble at the testing stage to a single deep neural network model while retaining the generalization. These three advances constitute the resulting technique FTBME. We conducted extensive experiments using deep neural networks, from light weight to complex, on ImageNet, CIFAR-10 and CIFAR-100. Results show that, given a deep neural network model which has been well-optimized and reaching its limit, FTBME can obtain better generalization with minor extra training expense while maintaining the expense to a single model at ensemble testing. This promising property of FTBME make us believe that it could be leveraged to broaden the usage for ensemble of deep neural networks, alleviating the situation that the engineering application field has not yet widespreadly benefited from ensemble of deep neural networks.

N-Doped mesoporous carbon spheres (N-MCSs) have shown important applications in many fields. Herein, N-MCSs with uniform spherical morphology, adjustable inner structure, and abundant mesoporous are prepared by a feasible co-assembly of an ionic liquid (IL), a silica precursor (tetraethoxysilane (TEOS)) and a carbon precursor (resorcinol/formaldehyde resin (RF)). The IL is used as a template on which TEOS and RF are assembled together through electrostatic interactions to form a spherical shape. Nitrogen in the IL results in N-doping of the carbon framework. Moreover, addition of TEOS can provide rich mesopores and cavity structures for the N-MCSs. The system solvent volume and RF amounts have a direct impact on the structure of the N-MCSs, changing from core–shell to hollow or from core–shell to solid carbon spheres. Different structures in the N-MCSs lead to distinct electrochemical properties as an electrode material. The N-MCSs have a unique core–shell structure, a crumpled surface, appropriate N-doping and a high surface area, which endows them with higher electrochemical properties of 350 F g−1 capacitance at 0.5 A g−1, good rate performance of 77.5% retention in the current density range of 0.5–10 A g−1, and long cycle life with 80.2% of the initial capacity after 10 000 cyclic tests, showing their promising potential to be used as an electrode material in supercapacitors.

Multi-element doped mesoporous carbon materials are considered as one of the most promising electrode materials for supercapacitors due to their large specific surface area, abundant mesoporous structure, heteroatom doping and good conductivity. Herein, the N, O co-doped ordered mesoporous carbon (N/O-OMC) were successfully prepared by the solid-solid grinding method using KIT-6 as template, Fe(NO3)3 as catalyst, and polyvinylpyrrolidone (PVP) as source of C, N, and O. The effect of PVP amount on the structural parameters of the sample was also discussed. The resulting N/O-OMC replicated the morphology of KIT-6 and showed suitable N and O doping, a large specific surface area and an ordered dual-mesoporous structure. As the electrode materials, N/O-OMC exhibit excellent specific capacitance of 229 F g−1 at 1 A g−1, excellent rate performance (79.5%) and cycle stability (92.3% after 5000 cycles). This multi-element doped mesoporous carbon material was proved a good candidate for high-performance electrode materials.

Herein, we report a confined pyrolysis strategy to prepare mesoporous carbon nanospheres by which surface area of carbon spheres is increased, pore size is enlarged and effective N-doping is achieved. In this method, the mesoporous polymer sphere as carbon precursor and 2-methylimidazole as nitrogen precursor are encapsulated in a compact silica shell which provides a confined nano-space for the pyrolysis treatment. The in situ generated gases from mesoporous polymer sphere and 2-methylimidazole under pyrolysis diffuse into the pores of mesoporous polymer sphere in the confined compact silica shell, resulting in increased surface area, larger pore size and N-doping due to self-activation effect. As electrodes in supercapacitor, the N-doped mesoporous carbon nanospheres exhibit a significantly enhanced specific capacitance of 326 F g−1 at 0.5 A g−1, which is 2 times higher than that of mesoporous carbon spheres under unconfined pyrolysis condition, exhibiting its potential for electrode materials with high performance.

Spiro-OMeTAD, which took place of PEDOT:PSS as hole transport material, was used to assist P3HT to transport holes. Inverted hybrid solar cells using P3HT and spiro-OMeTAD with layered (Device A) and/or blended (Device B) structures were fabricated. Power conversion efficiency of 1.24% was achieved for the latter device vs 0.53% for the former one. Here, the blended surface was smoother for closer electrical contact with the Cu electrode, leading to more efficient collection of holes. This study is the first report on layered and blended structures of ZnO-based inverted hybrid solar cells with P3HT and spiro-OMeTAD.

Carbon-based materials with different morphologies have special properties suitable for application in adsorption, catalysis, energy storage and so on. Carbon composites consisting of different morphologies are proved to improve the performance due to combination of favorable structural features. In this work, hollow carbon spheres/hollow carbon nanorods (HCS/HCR) composites are prepared by “dissolution–reassembly” combined with hard template method. Taking advantage of compositional inhomogeneity of 3-aminophenol/formaldehyde (3-AF) resin sphere, 3-AF oligomers are obtained by dissolution of resin sphere with acetone and then used to reassemble with silica oligomer on MnO2 nanorods template under the function of CTAB to form HCS/HCR composites after carbonization and removing template. The obtained HCS/HCR composites with combined characteristics of hollow sphere and hollow nanorod exhibit high surface area (1590 m2 g−1), large pore volumes (2.4 cm3 g−1), and uniform pore size distribution (9.3 nm). When used as electrode material, the obtained HCS/HCR composites show good specific capacitance of 250 F g−1 at a current density of 1 A g−1 in 6 M KOH aqueous electrolyte solution, as well as good cycling stability (91.3% capacity retention after 5000 cycles), suggesting that the HCS/HCR composites electrode materials have potential applications in high-performance supercapacitor.

Nitrogen-doped hollow mesoporous carbon spheres have drawn much attention in many applications, including adsorption, catalysis and energy storage, etc. because of their hollow structure, thin carb...

Hollow carbon nanostructures with tunable structure have inspired increasing interests in energy conversion/storage, biomedicine, catalysis, and adsorption, etc. However, rigorous control of textural properties is challenging. Herein, we report a novel, facile and mild encapsulation pyrolysis synchronous deposition strategy to synthesize hollow carbon spheres (HCSs) with tunable structure similar to moon phases during different stage. This method directly transform the polystyrene spheres, which are widely used as sacrifice hard template, into carbon by a pyrolysis process in an encapsulated silica shell without any cross-linking agent and catalyst. The tunable structure of HCSs is achieved in the compact silica shell which provides a hermetical nanospace to allow the encapsulation and deposition. These various hollow structures show interesting properties and potential for different applications, such as supercapacitors.

N-doped carbon spheres with different inner structure have attracted increasing attention due to their low density and high electrical conductivity in supercapacitors. Here, we reported controllable synthesis of hollow, yolk-shell and solid structure carbon spheres via template-free assembly method. Ethanediamine was used as nitrogen source to realize in-situ nitrogen doping and as basic catalyst to drive resorcinol-formaldehyde (RF) resin polymerization. The polymerization degree of internal RF resin tremendously depended on polymerization time, resulting in different levels of heterogeneity of the whole RF resin sphere. This fact made the structural adjustment of carbon spheres from hollow, to yolk-shell and even to solid structure after dissolution of low-molecular-weight RF resin by organic solvents and annealing treatment. As electrode material for supercapacitor, carbon spheres with yolk-shell structure exhibited excellent performance with capacitance of 242 F g−1 at the current density of 1 A g−1 and outstanding cycling life stability (97.3% after 5000 cycles), which may be attributed to its unique structure, high specific surface area (1263 m2 g−1) and pore volume (0.68 cm3 g−1). The strategy of making full use of the difference of polymerization degree of resin provides a new idea for the structural engineering of functional carbon materials.

Carbon spheres with rich porous structure are regarded as ideal materials for practical supercapacitors because of their excellent thermal stabilities, large surface areas, high electrical conductivities and good cycle stabilities. In this work, a novel dissolution–reassembly method is developed for the fabrication of rich porous carbon spheres (PCS) with high capability for supercapacitor. The resorcinol–formaldehyde resin is firstly synthesized then completely dissolved by acetone into oligomer fragments which further reassemble with F127 to form new structured resin spheres. After carbonization, PCS are obtained. The obtained PCS have regular spherical morphology, rich porous structure, high specific surface area and pore volume. As electrode material for supercapacitor, the PCS exhibit excellent performance with capacitance 240 F g−1 at the current density of 1 A g−1 and outstanding cycling life stability (98.1% after 5000 cycles) at the current density of 5 A g−1, showing the great potential for supercapacitor.

Carbon nanotube (CNT) has been intensively studied as supercapacitor electrode materials due to their high mechanical strength and excellent electrical conductivity. However, CNT with limited accessible surface area has low specific capacitance, which limits its application and development in supercapacitor. Herein, we have designed a thin N-doped porous carbon layer-modified CNT nanocomposite by template-free method. In this process, 3-aminophenol and formaldehyde rapidly self-assemble on the CNT in the presence of cationic surfactant CTAB, forming the composite of 3-aminophenol/formaldehyde (3-AF) resin and CNT. Due to the different polymerization degree of inside 3-AF resin, the soluble 3-AF resin oligomer was removed by acetone to form porous 3-AF resin and CNT@N-doped porous carbon (CNT@N-PC) was obtained by annealing process. The CNT@N-PC exhibited abundant porous structure, high specific surface area of 940 m2 g−1, excellent specific capacitance value of 224 F g−1 at 1 A g−1 and good cycle stability, demonstrating its potential as supercapacitor electrode materials.

Yolk–shell carbon spheres (YCS) have been widely used in many fields due to their abundant electron transport paths, high ion-accessibility and surface area as well as excellent mechanical properties. However, up to the present, the preparation of yolk–shell carbon spheres with tunable structures has always been a challenge. Herein, the direct conversion of solid resin spheres into YCS is achieved by a facile confined pyrolysis strategy. A silica shell with different degrees of openness is built on the surface of a solid resin sphere to form a confined nanospace, in which the volatile gases generated in the process of pyrolysis are deposited, forming a tunable yolk–shell structure. The results show that the YCS samples prepared in a relatively compact confined environment (YCS-C) have a thinner shell, higher surface area and richer porous structure. As electrode materials for supercapacitors, YCS-C show an excellent specific capacitance of 330 F g−1 at 0.5 A g−1 and outstanding stability with 88.5% initial capacity retention after 10 000 cyclic tests, making them promising candidates for high-performance energy storage devices.

Carbon composite materials with diverse structures show enhanced electrochemical performance as electrodes in energy storage devices than single component structures. Herein, rich mesoporous carbon nanosheets embedded with vesicle structures (CS-v) were prepared by a simple synergetic assembly strategy using 1-octadecyl-3-methylimidazolium bromide ([C18Mim]Br) as the surfactant, phenolic resin as the carbon precursor, silica precursor as an additive and iron(III) nitrate as the catalytic active center. [C18Mim]Br played an important role in the formation of flake morphology and nitrogen doping. The silica created a rich mesoporous structure on the CS-v, which improved the surface area. The addition of iron(III) nitrate not only creates vesicle structures but also leads to thinner sheets for CS-v, which accelerates the transfer and storage of charge, and improves the electrochemical performance. When used as the electrode in a supercapacitor, CS-v showed a high specific capacity of 341 F g−1 at the current density of 1 A g−1 in a three-electrode system, which is more than ca. 2.5 times enhancement compared with that of pure mesoporous carbon nanosheets, and an excellent long cycling ability with 99.5% of the initial capacity was retained after 10 000 cyclic tests, demonstrating its potential in energy storage devices.

Due to the characteristics of high specific surface area, abundant mesoporous structure and good electrochemical performance, mesoporous carbon materials are considered as good electrode materials in supercapacitors. In this report, we have successfully prepared nitrogen-doped mesoporous carbon (N-MC). First, tetraethyl-orthosilicate is hydrolyzed and self-polymerized to form mesoporous silica. Meanwhile, an aniline monomer is adsorbed and polymerized in the channel of mesoporous silica under catalysis with iron. After removing the silica and iron species, the resulting N-MC is rich in nitrogen, and has a mesoporous structure and a large specific surface area (1172 m2 g−1). As an electrode material, in 6 M KOH aqueous solution in a three-electrode system, N-MC exhibits an excellent specific capacitance of 334.5 F g−1 at 0.5 A g−1 and shows good cycle stability (88.5% after 5000 cycles) at 5 A g−1, maintaining 81.1% of the original capacitance even at high current densities, demonstrating the enormous potential of N-MC in supercapacitor applications.

Biomass is a common carbon precursor, because of its low cost, easy access and wide sources. However, direct pyrolysis of biomass usually leads to some disadvantages such as morphology destruction, low surface area and poor porosity. Herein, a silica-confined activation strategy is developed to prepare nitrogen-doped (N-doped) porous carbon microcapsule using the renewable biomass carbon precursor of yeasts. The yeasts are wrapped by a dense silica shell, forming a limited space, which can effectively avoid the destruction of yeast morphology during pyrolysis. The pyrolysis gas derived from yeast cannot overflow due to the limitation of confined space, and it plays an in-situ activator to result in layer structure with thin wall, abundant pores and high specific surface area (870 m2 g−1). Moreover, the N-doped porous carbon microcapsule possesses a higher certain of N-doping than the carbon product derived from direct pyrolysis of yeasts. As electrode materials in supercapacitor, the N-doped porous carbon microcapsule exhibits high capacitance of 316 F g−1 at 1 A g−1 with obvious enhancement of electrochemical performance compared with the carbon product derived from direct pyrolysis of yeasts, indicating the promise as a new electrode material in energy storage.

Central nervous system is a rare occurring location of solitary fibrous tumors (SFTs). SFTs have a potential for recurrence, which is the leading cause of death in patients with these disease entities. De-differentiation phenomenon combined with cerebrospinal fluid (CSF) dissemination through drop metastasis of STFs from intracranial to intraspinal has only been reported in extremely limited cases.Herein, we present a case of SFT in a 54-year old male. MRI showed characteristic of mixed high and low signal with 6.3 cm × 6.5 cm × 5.9 cm. After radical surgical resection, the pathology indicated benign SFT. However, MRI re-examination of 22 months later detected local recurrence, concomitant with spreading of intracranial and intraspinal through CSF dissemination. And interestingly, the second pathology found de-differentiation phenomenon and malignance of SFT, in which some areas transformed to rhabdomyosarcoma.This is the first case report of recurrent intracranial SFT de-differentiating to rhabdomyosarcoma concurrent with CSF pathway drop metastasis. Benign intracranial SFTs have the potential of de-differentiation, which may play an important role in its distant metastasis. The underlying molecular biological and pathological mechanisms of benign SFT malignance transformation still warrant further exploration.

BACKGROUND The aim of this study was to explore the upregulated nuclear factor kappaB (NF-kappaB)/microRNA-155 (miR-155) in regulating inflammatory responses and relapse of chronic rhinosinusitis (CRS) with nasal polyps (NP), which underlies the molecular mechanism of glucocorticoid treatment. MATERIAL AND METHODS The study recruited 25 patients with eosinophilic (Eos) CRSwNP, 25 patients with Non-Eos CRSwNP, 25 patients with CRS without NP (CRSsNP) and 30 patients with nasal septum deviation (control group). The expression of NF-kappaB/miR-155 and inflammatory cytokines was detected in epithelial tissue specimens. Additionally, a mouse model of Eos CRSwNP was established, and the mice were treated by NF-kappaB inhibitor, miR-155 antagomir, or dexamethasone (DEX) to explore the role of NF-kB/miR-155 and the anti-inflammatory effects of glucocorticoid treatment. RESULTS Results showed that the expression level of NF-kappaB/miR-155 was significantly elevated in the Eos CRSwNP group, accompanied by the upregulation of cytokines: tumor necrosis factor (TNF)-alpha, interleukin (IL)-1, IL-4, IL-5 (P

In this work, we reported on the effect of adjusted technical conditions on device morphology including inorganic semiconductor ZnO and the obtained active layers. Specifically, by different concentrations of sol–gel precursors and various hydrothermal time, density and length of ZnO nanorods were controlled; then the stacking of polymer chains was regulated with the thermal treatment temperature; and hole transporting property of PEDOT:PSS was adjusted with different spin-coating layers. Through a series of technical control, the cell devices performance was improved to 1.44% under 100 mW cm−2 step by step. The intrinsic mechanisms about charge separation, transport, and recombination kinetics were systematically discussed by various optical and electrochemical techniques.

Nitrogen-doped hollow carbon spheres (N-HCS) show advantages of regular hollow structure, large surface area, and nitrogen functionality, which make them widely applied in many fields, especially as electrode materials for supercapacitors. Herein, we demonstrated a facile way to prepare N-HCS by using SiO2 spheres as hard template, resorcinol-formaldehyde resin as carbon precursor. Polyvinyl pyrrolidone (PVP) was specially applied to introduce nitrogen and concurrently help resin coat on the surface of SiO2. With assistance of PVP, the resin uniformly coated on the surface of SiO2 by electrostatic adsorption and hydrogen bonding force and agglomeration of SiO2 spheres was prevented, resulting in improved dispersity of carbon spheres. The obtained N-HCS duplicated the morphology of the silica spheres faithfully with regular hollow structure and smooth surface, showing high surface areas and large pore volumes. As electrode material for supercapacitors, N-HCS exhibited good electrochemical performances with capacitance of 173 F g−1 at the current of 0.5 A g−1 and favorable cycling stability of 96.4% after 5000 cycles at current density of 5 A g−1, which make N-HCS become promising electrode material for high-performance supercapacitors.

The organic-inorganic heterojunction interface of hybrid solar cells plays an important role on the cell performance. The properties of heterojunction interface were modulated by employing two small organic molecules. The results showed that the introduction of organic molecules could improve the compatibility between the organic and inorganic materials, accelerate excitons separation efficiency and suppress carriers recombination. The power conversion efficiency of device was improved from 0.23% to 1.41%. Furthermore, the charge lifetime and interface charge transfer/recombination mechanisms were analyzed in detail. The intrinsic factors affecting the cell performance were investigated by electrochemical impedance and open circuit voltage decay measurements.

Mesoporous tubular carbon (MTC) with high specific surface area has attracted increasing attention due to their low density, fast ion diffusion and good electrical conductivity for supercapacitors. In this work, MTC was synthesized by using resin as carbon precursor, natural tubular Halloysite and F127 as hard-soft templates respectively. The resulted MTC copied the tubular structure of Halloysite. The addition of F127 not only created more abundant pores, but also greatly improved the surface area. The N2 adsorption experiments showed that the MTC possesses a large specific surface area (1034 m2 g−1) and large pore volumes (2.62 m3 g−1). The TEM of MTC showed an obvious tubular structure with abundant mesoporous structure. As the electrode material, MTC had good electrochemical capacitance (232 F g−1) at current density of 1 A g−1 and excellent cycling stability (95.3% after 5000 cycles) at the current density of 5 A g−1 in 6 M KOH electrolyte. The strategy may offer a low-cost and scalable method to produce high-performance electrode materials by using inexpensive natural product as a template.

Two-dimensional (2D) porous carbon nanosheets attract great attention because of their thin sheet-like morphology, abundant pores and high specific surface area, and their potential applicability in many fields including adsorption, oxygen reduction reaction, organic transistor and energy storage. Herein, a feasible method, named self-templating, to prepare 2D nitrogen-doping hierarchically porous carbon nanosheets (N-HPCNs) with prominent performances as supercapacitor electrode is reported. During the process of preparation, the inexpensive and easily available MgO rods are treated in water to form Mg(OH)2 nanosheets further using as templates and then nitrogen contained resorcinol–formaldehyde resin oligomers as carbon and nitrogen precursor co-condense onto the templates by electrostatic interaction. The obtained N-HPCNs with large specific surface area, hierarchical pores and unique interconnected sheet-like structure are the potential candidates for high energy storage devices. As an active electrode material for electrochemical double-layer capacitors, N-HPCNs exhibit a capacitance of 201 F g−1 at current density of 1 A g−1 and high specific capacitance (78.1% retention of initial capacitance even at 10 A g−1), with excellent cycling life stability (3.5% loss after 5000 cycles).

Wound environment-responsive materials show great potential in skin repair. Herein, a temperature-responsive fibrous hydrogel was developed with the aid of the phase-change material of natural fatty acids. The extracellular matrix-like methacrylate gelatin (GelMA) nanofibrous hydrogels were fabricated via electrospinning and UV-crosslinking, followed by a depot of fatty acids/aspirin (ASP) encapsulated polydopamine (PDA). The as-prepared fibrous hydrogels showed a significantly faster ASP release at 40 °C compared with those of 25 °C and 37 °C, and an “on-off” drug release was achieved at heating and cooling cycles between 40 °C and 25 °C. The in vitro cell culture tests and in vivo wound healing study proved that GelMA-PDA-ASP nanofibrous hydrogels facilitated the cell growth and accelerated wound repair. Taken together, the thermosensitive drug-releasing nanofibrous hydrogel, showed a great potential for wound care.

The chemical incompatibility at the organic-inorganic heterojunction interface in hybrid solar cells is a serious issue that cannot be ignored. In this work, four Ru-based dye complexes (D-series organic dyes) were employed for the interfacial properties modulation. The results showed that the introduction of organic molecules can not only improve the compatibility between the organic and inorganic materials, but also provide an appropriate energy levels alignment of the materials in the hybrid films. A notable power conversion efficiency of 2.91% was achieved. The intrinsic factors that affecting the cells performance were investigated by electrochemical impedance and open circuit voltage decay measurements.

Hollow mesoporous carbon spheres (HCS) are widely used in many fields, such as supercapacitors, adsorption, separation, batteries, etc., due to their large specific surface area, large cavity, thin mesoporous shell and good chemical stability. Herein, N-doped HCS was prepared using the pyrolysis-deposition method, with cetyltrimethylammonium bromide (CTAB) micelles derived from a hard template of solid silica core coated with mesoporous silica (SiO2@mSiO2), as the carbon and nitrogen precursor. This method realizes direct carbon formation from the decomposable surfactant CTAB, which avoids the need for other carbon precursors and simplifies the preparation process. The mesopores on the SiO2@mSiO2 template shell provide limited space and the transition metals provide active sites, which promotes the deposition of carbon derived from surfactants. The shell thickness of HCS can be adjusted by the thickness of the SiO2@mSiO2 template shell, which leads to a change in the morphology, i.e. from imperfect (macropore) hollow spheres to complete hollow spheres and transformation of the surface from rough to smooth. Ultimately, the resultant HCS completely replicates the morphology of the template and shows a uniform spherical shape with a mesoporous shell, a cavity, a high specific surface area and suitable N-doping content, which ensures good electrochemical performance as an active electrode material in supercapacitors.

Biomass-derived carbon has been the focus of research for a long time due to its wide range of sources, rich diversity and low cost. However, it also faces poor pore size distribution, low surface area and inert surface, which leads to its low performance, especially in supercapacitor. Herein, nitrogen enriched porous carbons (N-PC) were synthesized via a simple silica-activation process using carrots biomass as carbon precursor and Na2SiO3 as effective activation agent. Direct grinding for mixing of carrots and Na2SiO3 avoids the utilization of any solvents, leading to the characteristics of easy operation, simplicity and large-scale application. Carrots are rich in vitamins, which makes them serve as excellent carbon and nitrogen precursor. The low-cost Na2SiO3 plays an activating role to create porous structure, realizing the adjustment of mesopore size and increasing surface area for the N-PC. The prepared N-PC exhibits layered morphology, high surface area, rich porous structure, and nitrogen doping, which endow the N-PC with outstanding performance in the field of supercapacitor, indicating its promising for energy storage application.