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Abstract: In this paper, we discussed recent studies done in our laboratories with a floating catalyst chemical vapor deposition (CVD) method. We can grow single- or double-walled carbon nanotubes (SWNTs/DWNTs) with different kinds of catalysts. Single-walled carbon nanotubes without amorphous carbon coating were prepared by thermally decomposing acetylene (C2H2) at the temperature range of 750–1200°C with ferrocene as catalyst. While with sulfur promoted ferrocene catalyst, double-walled carbon nanotubes were mass-produced by pyrolizing C2H2 at the temperature range of 900–1100°C. Furthermore, tunable growth of DWNTs with different diameter was achieved in our experiment. It is found that DWNTs produced at lower carbon partial pressure have much smaller inner tubes, even DWNTs with the smallest inner diameter of 0.4nm was found in here. As convenient and effective tool, radial breathing mode (RBM) of Raman scattering technique can be used to distinguish SWNTs from DWNTs. In further studies of Raman scattering with DWNTs, the possible match of the inner tubes and the outer tubes according to the RBM bands was assigned, and different chirality types were discussed according to the diameter and chirality dependence of resonant Raman vibration. We also investigated the temperature-dependent frequency shift of resonant Raman spectra of DWNTs in the range of 78–650K. We found that different RBM peaks, which are relative to different tube diameters, have different temperature coefficient of frequency shift, and the larger diameter carbon nanotubes have more RBM frequency downshift with increasing temperature. It is ascribed to the RBM frequency variation to the temperature dependence of the stretching force constant of C–C bond. Besides, Polarized Raman spectra were preformed on well-aligned SWNTs structure fabricated through post-growth method and found that the angular dependence of Raman intensity is consistent well with the predictions of the resonance Raman theory. [Copyright &y& Elsevier]

Large size C70 single crystals with the dimension of more than 5 mm are grown from the vapor phase by controlling nucleation. X-ray diffraction and electron diffraction confirm that in the C70 single crystal a phase of the hexagonal close-packed (hcp) structure coexists with a minor face-center-cubic (fcc) phase at room temperature. The morphologies and their formation mechanism of the C70 single crystals are investigated by means of scanning electron micrascopy and optical microscopy. The influence of growth conditions on the morphologies of C70 single crystals is discussed. [ABSTRACT FROM AUTHOR]

The growth of carbon nanotubes from catalytic thermal decomposition of acetylene on fine iron particles has been studied. Electron microscopic images of the carbon nanotubes “as formed” and after annealing treatment are presented. Besides the ordinary carbon nanotubes which have been reported (S. Iijima, Nature, 354 (1991) 56), we have found, at first time, two other new kinds of carbon nanotubes: one is straight or curved nanotube with many irregular multi-layered diaphragms in the hollow core, in particular, the fringes of the wall of the tubes are not parallel to the axis of the tube; another one has many regular diaphragms (bamboo-like) which keep almost constant distance with each other. A model that postulates two steps growth of nanotubes from catalyst particles is proposed to explain the microstructure of the novel carbon nanotubes. [ABSTRACT FROM AUTHOR]

Sintering-free, dispersive, large area and high density carbon nanotubes(CNTs) were obtained in arc-discharge. Both the quality and the production of the CNTs were improved. SEM study showed that the dispersive CNTs intertwined and aligned randomly in the sample. The growth mechanism of the CNTs and the formation of the morphologies in the arc-discharge were discussed. [ABSTRACT FROM AUTHOR]

Presents information on the properties involved in the growth of crystals. Description of the detailed procedures in crystal growth; Discussion on the results following the growth of crystals.

Constrained by the large mode loss, it is a challenge to achieve low threshold lasing in a thin nanowire whispering-gallery-mode (WGM) cavity at room temperature (RT). Here, we demonstrate low threshold single-mode polariton lasing at RT in a thin ZnO nanowire (165 nm in diameter) on Al 2 O 3 layer/rough Ag film. Such a structure can compensate the whispering-gallery mode loss and enhance the WGM polariton emission in UV region for subwavelength ZnO nanowires. They are attributed to the strong local electromagnetic field near nanowire induced by Ag film. The polariton lasing is confirmed by the low threshold, narrowing of the linewidth at threshold, nonlinear intensity-power dependence and continous blueshift of the emission. A clear transition from strong coupling regime to weak coupling regime is observed with increasing pump power. This work suggests low-cost and high-performance room-temperature nanolasers or polariton devices achieved in single thin ZnO nanowires. Low threshold single-mode polariton lasing is achieved at room temperature in a thin ZnO nanowire (165 nm in diameter) on 10 nm-Al 2 O 3 layer/100 nm-rough Ag film. Image 1 • The thinnest ZnO nanowire worked as a WGM nanocavity is 165 nm in diameter. • The formation of WGM polaritons has been efficiently promoted in subwavelength ZnO nanowires on 10 nm-Al 2 O 3 layer/100 nm-rough Ag film by LSPs. • The low threshold single-mode polariton lasing can be produced in a thin ZnO nanowire of 165 nm in diameter, in which the carrier screening effect may destroy the exciton-cavity photon strong coupling in this nanowire at high pump power. [ABSTRACT FROM AUTHOR]

The flexible zinc ion battery (ZIB) is deemed to be a promising candidate for flexible power supply due to its high security and low cost. However, conventional segregated battery configuration inevitably suffers from the relative displacement or detachment between two neighboring components at bending strain, which seriously degrade the performance of a flexible battery. Moreover, stubborn Zn dendrite drastically shortens the cycle life. Herein, by integrating Zn anode, zinc protective coating, polyamide separator and cathode into a single matrix, referred as the integrated electrode, a long cycle life and robust flexibility for ZIB in aqueous electrolyte are achieved. Seamless connection with the adjacent layers not only avoids the relative displacement or detachment caused by bending strain, but enhances the interfacial contact to promote the electrochemical kinetics. The built-in protective coating in the integrated configuration significantly inhibits the dendrites and side reactions for extending the durability. Furthermore, the integrated configuration makes the whole battery lighter, thinner and more powerful. Therefore, this work provides a new design idea for engineering innovative battery configuration and enables high performances for a flexible ZIB. Meanwhile, the research results would deliver great potential applications in flexible electronics and boost the development of configuration of energy storage devices. An ingenious configuration with robust interfacial contact is developed via the integration of Zn anode, zinc protective coating, polyamide separator and cathode into a single matrix, enabling the high flexibility and the dendrite-free boosted durability for zinc ion batteries. Image 1 • A flexible and durable zinc ion battery with integrated configuration is developed by manageable and scaleable process. • Continuous seamless connection prevents the displacement or detachment and ensures the steady electron transfer. • The built-in Zn anode protective coating inhibits dendrite growth and tightly glues the anode and polyamide separator. • The integrated configuration delivers significantly prolonged lifespan, reduced overpotential and boosted flexibility. [ABSTRACT FROM AUTHOR]

Cubic In2O3 microtubes were prepared by thermally oxidizing InN counterparts under controlled conditions. Similar to the starting InN sample, the converted In2O3 microtubes are hexagonal in cross section and exhibit helical motifs of both right-handed and left-handed architectures with helical angles of 0°–30°. InN microtubes can be retrieved by renitridation of the oxide microtubes. This work demonstrates that it is feasible to fabricate specific oxide nano-/microstructures from its corresponding nitride counterparts via controlled oxidation manner and vice versa. Temperature-dependent Raman scattering in both InN and In2O3 microtubes was measured and obvious downshifts of Raman modes were observed with increasing temperature. [ABSTRACT FROM AUTHOR]

High‐efficiency production of near‐zigzag single‐chirality single‐wall carbon nanotubes (SWCNTs) is of great importance for their property study and applications. The key to separate near‐zigzag single‐chirality SWCNTs by gel chromatography is to selectively adsorb them in the gel medium. In this study, by using a high surfactant ratio of sodium dodecyl sulfate and sodium cholate (≥4:1) to modulate the selective adsorption of distinct (n, m) SWCNTs in a gel column, a high enrichment of near‐zigzag SWCNTs adsorbed in the gel column is achieved, which usually have a low abundance in raw materials due to their low growth efficiency. Afterward, (7, 3), (8, 3), (8, 4), (9, 1), and (9, 2) single‐chirality SWCNTs are separated with small chiral angles less than 17° by following a stepwise elution for their selective desorption. This simple and efficient separation technique will promote the research and application of near‐zigzag SWCNTs. [ABSTRACT FROM AUTHOR]

Wild-type and mutant human p53 genes were transfected into the nasopharyngeal carcinoma (NPC) cell line CNE-3. Tumorigenicity in nude mice showed that the tumor resulting from the cells transfected with the wild-type p53 gene grew more slowly and was smaller than that from the cells transfected with mutant p53 gene and that from control CNE-3 cells. In contrast, the tumor from the cells transfected with the mutant p53 gene grew faster than that produced by cells transfected with the wild-type p53 gene and that produced by control CNE-3 cells. The results demonstrate that the wild-type p53 gene could inhibit the NPC cell growth in nude mice and the mutant p53 gene could enhance the NPC cell growth in nude mice. The p53 gene may also play an important role in the pathogenesis of NPC. [ABSTRACT FROM AUTHOR]

It is a great challenge to substantially improve the practical performance of flexible thermoelectric modules due to the absence of air-stable n-type thermoelectric materials with high-power factor. Here an excellent flexible n-type thermoelectric film is developed, which can be conveniently and rapidly prepared based on the as-grown carbon nanotube continuous networks with high conductivity. The optimum n-type film exhibits ultrahigh power factor of ∼1,500 μW m−1 K−2 and outstanding stability in air without encapsulation. Inspired by the findings, we design and successfully fabricate the compact-configuration flexible TE modules, which own great advantages compared with the conventional π-type configuration modules and well integrate the superior thermoelectric properties of p-type and n-type carbon nanotube films resulting in a markedly high performance. Moreover, the research results are highly scalable and also open opportunities for the large-scale production of flexible thermoelectric modules. [ABSTRACT FROM AUTHOR]

A high‐performing epidermal supercapacitor is presented W. Y. Zhou, Z. Q. Niu, S. S. Xie, and co‐workers on page 8178. The micrometer‐thin and extremely flexible supercapacitor can reveal the subtle skin texture and manifest a practical potential to power other devices, which is promising for future smart and epidermal systems. [ABSTRACT FROM AUTHOR]

Chirality separation of single-wall carbon nanotubes (SWCNTs) is key to enabling applications in single photon sources, optoelectronic devices and bioimaging, and it generally requires multiple separation steps to obtain single chirality species with the desired purity. In this work, we report the use of a novel sodium hyodeoxycholate (SHC) surfactant for separation of single-chirality SWCNTs. The results demonstrated that chirality-selective adsorption and desorption of SWCNTs on a gel column can be achieved readily by modulating the concentrations of the SHC-based mixed surfactants. Through an optimized one-step procedure, single-chirality (6,5) SWCNTs were successfully separated, and the chirality purity was estimated to be 97% by using a spectroscopic approach, exceeding most reported purities for traditional surfactant-based one- or multiple-step separations. Due to the ultrahigh chirality resolution of the present method, the (6,5) SWCNTs can also be effectively separated from different SWCNT materials with various diameter or chirality distributions, even from materials containing very few (6,5) SWCNTs. The high-purity chirality separation demonstrated in this work lays an important foundation for the industrial production and applications of single-chirality SWCNTs. [Display omitted] [ABSTRACT FROM AUTHOR]

Recent development in epidermal and bionic electronics systems has promoted the increasing demand for supercapcacitors with micrometer-thickness and good compatibility. Here, a highly flexible free-standing epidermal supercapacitor (SC-E) with merely 1 μm thickness and high performance is developed. Single-walled carbon nanotube/poly(3,4-ethylenedioxythiophene) hybrid films with unique inner-connected reticulation are adopted as electrodes for ultrathin structure and high electric conductivity. Then, based on two substrates with different surface energies, a stepwise lift-off method is presented to peel off the ultrathin integrated supercapacitor from the substrates nondestructively. As a result of the high conductive hybrid electrodes and the thin electrolyte layer, the as-designed supercapacitors (based on the total mass of two electrodes) achieve a good capacitance of 56 F g−1 and a superhigh power density of 332 kW kg−1, which manifest superior performance in contrast to the other devices fabricated by traditional electrodes. Meanwhile, the ultrashort response time of 11.5 ms enables the epidermal supercapacitor (SC-E) work for high-power units. More importantly, the free-standing structure and outstanding flexibility (105 times bending) endow the SC-E with excellent compatibility to be integrated and work in the next generation of smart and epidermal systems. [ABSTRACT FROM AUTHOR]

Abstract: Water molecules adsorbed on a double-walled carbon nanotube (DWCNT) serve as charge trapping centers when present in low density and as electron donors when present in high density. There is a discontinuous change between the low- and high-density regions. H2O molecules are apt to be adsorbed on the outer surface of DWCNTs, and in this case the electrical transport properties are extremely sensitive to environment, which suggests that DWCNTs are hole doped and act as an electric dipole with the inner tube. [Copyright &y& Elsevier]

Structural control of single-wall carbon nanotubes (SWCNTs) with uniform properties is critical not only for their property modulation and functional design but also for applications in electronics, optics, and optoelectronics. To achieve this goal, various separation techniques have been developed in the past 20 years through which separation of high-purity semiconducting/metallic SWCNTs, single-chirality species, and even their enantiomers have been achieved. This progress has promoted the property modulation of SWCNTs and the development of SWCNT-based optoelectronic devices. Here, the recent advances in the structure separation of SWCNTs are reviewed, from metallic/semiconducting SWCNTs, to single-chirality species, and to enantiomers by several typical separation techniques and the application of the corresponding sorted SWCNTs. Based on the separation procedure, efficiency, and scalability, as well as, the separable SWCNT species, purity, and quantity, the advantages and disadvantages of various separation techniques are compared. Combined with the requirements of SWCNT application, the challenges, prospects, and development direction of structure separation are further discussed. [ABSTRACT FROM AUTHOR]

The intersubband plasmons (ISBPs) of single‐wall carbon nanotubes (SWCNTs) endow SWCNT‐based optoelectronic devices with more functions. However, the structural dependence of the ISBPs of SWCNTs is not fully understood. Here, the effect of electronic types and diameters of SWCNTs on the energy and intensity of their ISBPs is investigated systematically. The results show that the ISBP energy of semiconducting SWCNTs is ≈50–250 meV larger than that of metallic SWCNTs with the same diameters, while the ISBP integral intensity is approximately 1.25 to 4 times stronger. Diameter dependence of ISBPs for both semiconducting and metallic SWCNTs is also observed. With a decrease in diameter, the ISBPs shift to higher energies, while the intensity decreases dramatically. When the diameter is reduced to less than 1 nm, the ISBPs become unobservable. Interestingly, the energy separation between the ISBPs and interband transition S22 (M11) decreases with an increase in diameter. Theoretical calculations show that the structure‐dependent ISBP characteristics are dominated by the electronic states of SWCNTs. Based on the ISBP characteristics of different SWCNTs, high‐performance SWCNT‐based near‐infrared electrochromic devices are fabricated by mixing small‐diameter metallic SWCNTs with semiconducting SWCNTs due to their high conductivity and negligible ISBP signals. [ABSTRACT FROM AUTHOR]

The presence of grain boundaries and defects in perovskite films can be detrimental to performance of perovskite solar cells (PSCs), such as leading to nonradiative recombination and environmental instability. Additive engineering is a key tactic to control crystal growth and passivate defects of perovskite film. In this work, lead-free alkali metal additive of potassium selenocyanate (KSeCN) was firstly added in precursor solution to prepare a novel perovskite of CH 3 NH 3 PbI 3-x (SeCN) x. The SeCN− is substitute for I− to enhance structure stability, simultaneously facilitate nucleation, meanwhile, effectively increase crystalline grain size and passivate the defects. Finally, the power conversion efficiency of planar perovskite solar cells boosts from 14.34% to 18.41%, and the hysteresis reduces from 21% to 1.5%, nearly negligible. Our findings provide an avenue for crystalline regulation and defects passivation to further improve the performance of perovskite solar cells and propose a promising CH 3 NH 3 PbI 3-x (SeCN) x -based perovskite. Image 1 • KSeCN was introduced to improve crystallization and defect passivation. • CH 3 NH 3 PbI 3-x (SeCN) x is a promising and stable perovskite. • Planar perovskite solar cells got a PCE of 18.41% and negligible hysteresis. [ABSTRACT FROM AUTHOR]

We report an innovative method for the fast preparation of wafer-scale uniform single-wall carbon nanotubes (SWCNT) films with controllable density by NaHCO 3 tuning the interaction between amine-functionalized substrates and surfactant-dispersing SWCNTs in aqueous solution. With this technique, a 4-inch SWCNT film with a linear density of ∼30 tubes/μm can be achieved in 1 s, and over 60 tubes/μm within 30 s using a high-concentration SWCNT solution. The SWCNT density changes by less than 8% over a 4-inch area. The electrical uniformity of the as-prepared wafer-scale single-chirality SWCNT film was demonstrated to be within 10.8% for subthreshold swing and 12% for carrier mobility and 13.5% for their on-current, which is the most uniform SWCNT films reported so far fabricated from the surfactant-dispersed SWCNT solution. Further, the photodetectors made by the uniform semiconducting SWCNT films exhibit excellent cascading ability, which linearly amplify the output photovoltages and could produce a photovoltage responsivity of 2.5 × 106 V/W. When three-stage cascading photodetectors are used as optical gate to establish an integrated photoelectric system, a 20-mW/cm2 light illumination produces the current responsivity of 147.3 A/W under a source/drain voltage of −0.1 V. Our present technique lays an important foundation for their applications in integrated circuits. Image 1 [ABSTRACT FROM AUTHOR]

High-efficiency separation of the enantiomers of (5, 4) single-wall carbon nanotubes (SWCNTs) is of great importance for the property study and applications of SWCNTs in bioimaging, chiral molecule screening and detection due to their high photoluminescence quantum efficiency and short emission wavelength. In this work, we introduced a new surfactant cholic acid (HC) with high hydrophobicity that has high resolution selectivity in modulating the selective adsorption of small-diameter SWCNTs in gel columns. With this technique, (5, 4) SWCNTs, which usually have few contents in raw mixture materials and undetectable due to their low growth efficiency, were highly selectively adsorbed in gel columns by tuning HC concentrations. Afterward, high-purity enantiomers of single-chirality (5, 4) SWCNTs were separated by the ternary surfactant system of sodium dodecyl sulfate, sodium cholate, and sodium deoxycholate to selectively desorb their enantiomers from gel columns. Based on their circular dichroism spectra, we further experimentally determined the exciton band structures of (5, 4) SWCNTs, which are distinctly different from the previous theoretical calculation results. These achievements not only provide an important material foundation for the applications of (5, 4) SWCNTs, but also give a deeper insight into the relationship between the chiral structures and intrinsic properties of SWCNTs. [Display omitted] [ABSTRACT FROM AUTHOR]

Lead acetate-based perovskite solar cells (PSCs) have shown their superiority in terms of controlled grain growth and replacement of traditional lead halides, which is critical for their large-scale commercial applications; however, the lack of control on the grain quality of lead acetate-based perovskite still creates risks such as unwanted defects, pinholes and grain boundaries. Herein, we proposed a reliable method to control the morphology and grain size of lead acetate-based perovskites along with a dynamic solvent-vapor annealing treatment; it was found that the vapors of N,N-dimethylformamide (DMF) assisted in the growth of perovskite grains and facilitated the increase in grain size. Using optimized DMF volume, the fabricated planar PSCs with the structure FTO/TiO2/perovskite/spiro-OMeTAD/Ag achieved the highest power conversion efficiency (PCE) of 13.71%, which was 23.8% higher than that of the controlled device. Moreover, the hysteresis effect was negligible. The results demonstrate that the solvent vapor-assisted crystal growth process is a simple and facile way to improve the quality of lead acetate-based perovskites and increase their performance. [ABSTRACT FROM AUTHOR]

Organometallic halide perovskite absorption layer with excellent surface morphology and large grain size is very important for fabricating efficient perovskite solar cells (PSCs). The antisolvent assisted crystallization (ASAC) has been proved to be an effective tactic to prepare compact and uniform polycrystalline perovskite film. However, most of the antisolvents currently used are highly toxic, and the perovskite crystallization process is difficult to control using pure antisolvent. Here, a green strategy is developed to improve the nucleation kinetics of perovskite precursor and the perovskite crystallization process. A mixed green antisolvent of ethyl acetate (EA)/petroleum ether (PE) is employed to regulate the crystallization of perovskite and replace traditional chlorobenzene (CB) and pure EA. With optimized proportion of EA and PE, the supersaturation degree is controlled via reducing the solvent evaporation rate and the nucleation rate, and it is good for crystal growth. Moreover, the grain growth rate and grain size are easily regulated, which contribute to the uniform, large grain and non-pinhole perovskite film. Correspondingly, the intrinsic perovskite solar cells based on CH 3 NH 3 PbI 3 achieve a power conversion efficiency of 17.19% and an average efficiency of 16.25% (std 0.43). Image 1 • A mixed green antisolvent of ethyl acetate (EA) /petroleum ether (PE) is employed. • The mixed green antisolvent regulated the crystallization of perovskite • The solution processing methods are suitable for large area manufacturing. [ABSTRACT FROM AUTHOR]

Surfactant-based separation techniques have been developed for the high-efficiency production of high-purity semiconducting single-wall carbon nanotubes (s-SWCNTs), which establish an important material foundation for the preparation of high-performance carbon-based electronic devices. However, surfactant molecules wrapping around SWCNTs during structural separation inevitably degrade the resulting device performances due to increasing contact resistance between the SWCNTs and electrodes and between individual SWCNTs. Here, we developed a simple and effective strategy for completely removing the surfactant molecules around separated s-SWCNTs by annealing and rinsing. With this technique, defects were not clearly increased in the crystal structure of SWCNTs, and the transport performances of SWCNT-based thin film transistors (TFTs), including the on-state current and mobility, were improved by approximately an order of magnitude, while the on-off ratio increased by nearly 1.5 orders of magnitude. Upon shortening of the channel lengths of the devices, high-performance TFTs were fabricated based on an increase in the proportion of individualized SWCNTs that directly connected the source and drain electrodes. The present technique provides an important foundation for promoting the development of carbon-based electronic devices. [Display omitted] [ABSTRACT FROM AUTHOR]

The structure separation of synthetic single-wall carbon nanotube (SWCNT) mixture species with diameters larger than 1.2 nm still remains a challenge. Here, an NaOH-assisted gel chromatography method is used for the structure separation of the SWCNT mixture with a diameter range of 1.2-1.7 nm, in which NaOH is used to tune the interaction between distinct ( n, m) SWCNTs and gel. Incrementally increasing NaOH concentration in SWCNT dispersion selectively enhances the adsorbability of different-structure SWCNTs and enlarges their interaction difference with gel, leading to their structure separation after applying into a gel column system. On this basis, a two-step method is developed for further improving the structure purity of the separated SWCNTs by combining overloading and stepwise elution. These results are well demonstrated by the optical spectra of the separated SWCNTs. This work paves a way for single-chirality separation of large-diameter SWCNTs using gel chromatography technique and is an advanced progress in the structure control of SWCNTs. [ABSTRACT FROM AUTHOR]

Supercapacitors (SCs), also called electrochemical capacitors, often show high power density, excellent charge/discharge rates, and long cycle life. The recent development of flexible and wearable electronic devices requires that their power sources be sufficiently compact and flexible to match these electronic components. Therefore, flexible SCs have attracted much attention to power current advanced electronics that can be flexible and wearable. In the past several years, many different strategies have been developed to programmably construct different nanocarbon materials into bendable electrode architectures. Furthermore, flexible SC devices with simplified configurations have also been designed based on these nanocarbon-based architectures. Here, recent developments in the programmable assembly of bendable architectures based on nanocarbon materials are presented. Additionally, the design of flexible nanocarbon-based SC devices with various configurations is highlighted. The progress made recently paves the way for further development of nanocarbon architectures and corresponding flexible SC devices. Future development and prospects in this area are also analyzed. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel heterogeneous lead iodide, exhibiting two (0 0 1) interplanar distances of 6.9 Å and 9.0 Å, was constructed. • The heterogeneous structure can regulate the crystallization process of PbI 2 and perovskite films. • The V OC and PCE were raised to 1.21 V and 24.24%. At present, the highest power conversion efficiency (PCE) of perovskite solar cells (PSCs) has exceeded 25%, which exhibits great potential for commercial applications. Obtaining pinhole-free, superior crystal, and high-quality perovskite films with fewer defects by adjusting the lead iodide (PbI 2) intermediate films in a two-step sequential deposition has become research arousing general interest. Herein, a heterogeneous lead iodide (HLI) structure with two (0 0 1) interplanar distances (9.0 Å and 6.9 Å), can optimize the crystallization process of perovskite to get better surface morphology and is constructed by intercalated choline chloride (a kind of vitamin B4, VB4). HLI simultaneously improves the carrier lifetime of perovskite film from 1.96 µs to 3.28 µs and reduces defect state density. Together with better morphology and lower defect state density, the open circuit voltage (V OC) and PCE based on (FAPbI 3) 0.97 (MAPbBr 3) 0.03 is significantly boosted. In addition, with double-sided modification, HLI produces an excellent PCE of 24.27% with a V OC of 1.21 V. We believe that the novel heterogeneous PbI 2 structure could be a generic method to improve the efficiency of PSCs. [ABSTRACT FROM AUTHOR]

Abstract: Carbon nanotube (CNT) fibers are a novel type of fibrous materials that show potential in polymeric composite fields. In this study, we investigated the interfacial behavior of a single single-walled carbon nanotube (SWCNT) fiber embedded in isotactic polypropylene (iPP) matrix. The SWCNT fibers were found to be able to act as a heterogeneous nucleating agent which inducing the formation of transcrystals around the fiber surface. According to the theory of heterogeneous nucleation, the interfacial free energy difference Δσ of iPP on the SWCNT fibers was determined and compared with that on the conventional fibers. By carefully controlling the crystallizing conditions, three types of α-iPP supra-molecular microstructures with different optical birefringences were obtained. Raman spectra were utilized to investigate the influences of the supra-molecular microstructures of the transcrystalline (tc) layer on the strain transfer efficiency from the matrix to the fibers at a microscopic level. Conventional single-fiber pull-out tests were further employed to compare with the results derived from the Raman tests. [Copyright &y& Elsevier]

Abstract: Heterostructures of side-to-side biaxial ZnS/Zn2SnO4 (ZTO) nanowires have been fabricated via a simple one-step thermal evaporation process. Structural characterization by high-resolution transmission electron microscopy and electron diffraction indicates that both the face-centered cubic spinel ZTO subsection and the wurtzite ZnS subsection of the heterostructure are well crystallized with a distinct interface along the heterostructure axial direction. Based on detailed analysis of the growth process of biaxial ZnS/ZTO nanowire heterostructures, there are two dominating stages: a vapor–liquid–solid (VLS) controlled growth of ZTO sub-nanowire and a self-assembly growth of ZnS sub-nanowire onto the preformed ZTO base nanowire. A growth model of the heterostructures is proposed. The presented method would be flexible and feasible for the synthesis of other nano-heterostructures with non-oxide/oxide interface to meet the growing demands of nanoscale science and technology. [Copyright &y& Elsevier]