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The degradation and stability behavior of AISI 4130 steels have been examined under high-temperature dynamic plasma flame environments. A Fe2Al5 layer was formed as a result of aluminizing on the steel. An Al2O3 layer was produced on top of the Fe2Al5 layer, when the coated steel was oxidized at 500 °C (pre-oxidation treatment). The uncoated steels and the Fe2Al5 coated steels (i.e., the aluminized steels) showed large weight loss and complete changes in their original shapes due to their melting during the plasma flame tests at 1480 °C. However, the steels with the Al2O3 and Fe2Al5 (pre-oxidation treatment) were very stable without showing noticeable weight loss even after exposures to the plasma flame tests mainly due to the presence of the Al2O3 layer. SEM and XPS analyses were used to provide the presence of Fe2Al5 and Al2O3 phases on the surface. The effects of synthesized surface layers of the steels on high-temperature plasma flame exposure are discussed together with the surface morphology and microstructural observations.

Halide perovskite solar cells have been attracting tremendous attention as next-generation solar cell materials because of their excellent optical and electrical properties. Formamidinium lead tri-iodide (FAPbI3) exhibits the narrowest band gap among lead iodide perovskites and shows excellent thermal and chemical stability, also. However, the large-area coating of FAPbI3 needed for commercialization has not been successful because of the instability of the black phase of FAPbI3 at ambient temperature. This study presents a compositional engineering direction to control the polymorph of the FAPbI3 thin film for the shear coating processes, without halide mixing. By adopting a hot substrate above 100 oC, our shear coating process can produce the black phase FA-based halide perovskites without halide mixing. We carefully investigate the Cs-FA and MA-FA mixed lead iodide perovskites’ phase stability by combining the study with thin-film fabrication and ab initio calculations. Cs-FA mixing shows promising behaviors for stabilizing α-FAPbI3 (black phase) compared with MA-FA. Stable FA-rich perovskite films cannot be achieved via shear coating processes with MA-FA mixing. Ab initio calculations revealed that Cs-FA mixing is excellent for inhibiting phase decomposition and water incorporation. This study is the first report that FA-based halide perovskite thin films can be made with the shear coating process without MA-Br mixing. We reveal the origin of the stable film formation with Cs-FA mixing, and present future research directions for fabricating FA-based perovskite thin films using shear coating.

CdS has been known to be one of the best junction partners for Cu(In,Ga)Se2 (CIGS) in CIGS solar cells. However, the use of thick CdS buffer decreases the short-circuit current density of CIGS solar cells. There are two obstacles that limit the use of ultrathin CdS. The first is plasma damage to CIGS during the preparation of transparent conducting windows and the second is a low shunt resistance due to the direct contact between the window and CIGS via pinholes in the thin CdS buffer. In other words, to avoid plasma damage and shunt paths, we may have to use a CdS buffer that is thicker than necessary to form a high-quality CdS/CIGS junction. This work aims to determine how thin the CdS buffer can be employed without sacrificing device performance while also eliminating the above two obstacles. We investigate the effect of CdS thickness on the performance of CIGS solar cells with silver nanowire-based window layers, which can eliminate both obstacles. An approximately 13 nm thick CdS buffer allows us to achieve high short-circuit current density and fill factor values. To attain an even high open-circuit voltage, an additional CdS buffer with a thickness of 13 nm is needed. The data from this study imply that an approximately 26 nm thick CdS buffer is sufficient to form a high-quality CdS/CIGS junction.

In this study, we tried to improve the oxidation resistance of Nb-12Si (wt%) alloys at 1200 °C or higher through pack cementation coatings. Nb-12Si (wt%) alloys were prepared by arc-melting under Ar atmosphere. When the alloys were coated using pack powder mixtures composed of Si, Al2O3 and NaF, two silicide layers composed of NbSi2 and Nb5Si3 phases were successfully produced on the substrate. The Si-pack coatings were performed with various heat treatment temperatures and time conditions. The microstructures and thickness changes of the coating layers were analyzed to determine the growth behaviors of the coating layer. The growth constant of 8.4 10–9 cm2/sec was obtained with a diffusion growth mode. In addition, in order to examine the resistance of the Si-pack coated alloys, isothermal static oxidation tests were performed at 1200 °C and higher temperatures. As a result, the oxidation resistance of the alloys was determined by protecting the surface of the alloys with silicide oxide layers formed by the silicide coatings. The uncoated specimens exhibited an abnormal weight increase due to the formation of Nb oxide. The coated specimen showed excellent oxidation resistance at 1200 °C for up to 12 hrs, while the previous reports on the same alloy verified oxidation resistance only up to 1100 °C. It appears that the excellent oxidation resistance is closely related to the NbSi2 coating layer thickness. The oxidation behaviors of the coating layers after the oxidation tests were discussed in terms of microstructural and phase analyses.

We report optical phonon vibration modes in ensembles of self-catalyzed InP/InAs/InP multi core-shell one-dimensional nanostructures (nanopillars and nanocones) grown on InP(111)B substrates using liquid indium droplets as a catalyst via metal-organic chemical vapor deposition. We characterized the Raman vibration modes of InAs E1(TO), InAs A1(TO), InAs E1(LO), InP E1(TO), InP A1(LO), and InP E1(LO) from the ensemble of as-grown nanostructures. We also identified second-order Raman vibration modes, associated with InP E1(2TO), E1(LO+TO), and E1(2LO), in the InP/InAs/InP core-shell nanopillars and nanocones. Raman spectra of InP/InAs/InP nanopillars showed redshift and broadening of LO modes at low-frequency branches of InAs and InP. Due to the polar nature in groups III–V nanowires, we observed strong frequency splitting between InAs E1(TO) and InAs A1(LO) in InP/InAs/InP nanocones. The Raman resonance intensities of InP and InAs LO modes are found to be changed linearly with an excitation power. By tilting the substrate relative to the incoming laser beam, we observed strong suppression of low-frequency branch of InP and InAs LO phonon vibrations from InP/InAs/InP nanocones. The integrated intensity ratio of InP E1(TO)/E1(LO) for both nanostructures is almost constant at 0-degree tilt, but the ratio of the nanocones is dramatically increased at 30-degree tilt. Our results suggest that Raman spectroscopy characterization with a simple substrate tilting method can provide new insights into non-destructive characterization of the shape, structure, and composition of the as-grown nanostructures for the wafer-scale growth and integration processing of groups III–V semiconducting hetero-nanostructures into nanoelectronics and photonics applications.

Transparent conducting electrodes are essential components in various optoelectrical devices. Although indium tin oxide thin films have been widely used for transparent conducting electrodes, silver nanowire network is a promising alternative to indium tin oxide thin films owing to its lower processing cost and greater suitability for flexible device application. In order to widen the application of silver nanowire network, the electrical conductance has to be improved while maintaining high optical transparency. In this study, we report the enhancement of the electrical conductance of silver nanowire network transparent electrodes by copper electrodeposition on the silver nanowire networks. The electrodeposited copper lowered the sheet resistance of the silver nanowire networks from 21.9 Ω/□ to 12.6 Ω/□. We perform detailed X-ray diffraction analysis revealing the effect of the amount of electrodeposited copper-shell on the sheet resistance of the core-shell(silver/copper) nanowire network transparent electrodes. From the relationship between the cross-sectional area of the copper-shell and the sheet resistance of the transparent electrodes, we deduce the electrical resistivity of electrodeposited copper to be approximately 4.5 times that of copper bulk.

The authors have recently reported the enhanced thermal stability of silver nanowire (AgNW) network transparent electrodes by electrodeposition method [1]. AgNW networks are known to break into droplets at elevated temperatures (spherodization temperature) that are still much lower than the bulk Ag melting temperature. This phenomenon is known as Rayleigh instability. As the diameter of individual AgNW in the network increases by electrodeposited Ag on the AgNW surface, the thermal stability of AgNW network can be enhanced. Here, we provide the data on the spherodization temperature depending on AgNW diameter. We also report the calculated activation energy required to induce the spherodization of AgNW network.

Ti-6Al-4V(Ti64) alloy has excellent mechanical properties and corrosion resistances, but poor oxidation properties at high temperatures. It is necessary to improve the oxidation resistances of the alloy in order to expand its application in the aerospace and automotive fields. This study aimed to improve oxidation resistances through diffusion coatings on the surface of the alloy. Aluminide coatings on Ti64 alloys have been investigated via pack aluminium process at temperature ranges of 400–800 °C. Al and/or TiAl3 layers were formed at the interface between the Ti64 alloy and the Al coating layer, when the Ti64 alloys were heat-treated at 400 and 500 °C. TiAl3 layer was manufactured on Ti64 alloys at 600, 700 and 800 °C. The growth of the coated TiAl3 layer followed diffusional growth manner, and the estimated value of the nucleation barrier was the lowest among the intermediate phases of the Ti-Al system. The coating kinetics were discussed together with free energy diagram observations. The activation energy for growth of the TiAl3 layer was estimated as ~82 kJ/mol in the experimental temperature ranges. At the same time, isothermal oxidation tests of the bare Ti64 alloy and the aluminized Ti64 alloys were performed at 1000 °C. By confirming the diffusion pathway of the Ti-Al-O ternary system, the oxidation behaviours and resistances of the alloys were compared and analysed.

To achieve a surface-enhanced Raman spectroscopy (SERS) sensor that is easy to make and use, we propose periodic gold nanotrench arrays, which can be fabricated without surface contamination and intricate sensor alignment. Deep and narrow plasmonic nanotrenches for amplifying local electromagnetic fields were reliably generated on a wafer-scale substrate by nanoimprint lithography and two successive oblique-angle depositions. Electromagnetic simulations and Raman measurements show that the proposed plasmonic nanostructures function as SERS sensors, enabling nanomolar sensitivity. Furthermore, we successfully confirmed the microRNA detection capability of the proposed nanostructures to demonstrate their promising potential and feasibility for use in biomedical diagnostic sensors.

Research is being conducted on Mo- and Nb-based alloys that are used in the aerospace sector, including those used for advanced gas turbines and aircraft engines. There is a limit to using Mo, which has a high density among refractory metals, and a few studies exist describing the addition of Nb to Mo&ndash, silicide alloys. There is a lack of guidance research on the basic Nb:Mo ratio of alloys, and it is necessary to study how to improve oxidation resistance. Therefore, this study aims to improve oxidation resistance by controlling the ratio of Nb and Mo in (Nbx, Moy)Si2 coating layers with Si pack cementation coatings on Nb&ndash, Mo alloys. Static oxidation tests were carried out at 1200 &deg, C for 6 h to confirm the oxidation characteristics. As a result, a SiO2 or SiO2 + Nb2O5 ceramic protective layer was formed on the surface. After the oxidation tests, alloys with a Nb content of less than 35 at.% were found to protect the surface. The ratios of Nb and Mo in the Nb&ndash, Mo alloy and silicide coating layer were compared, and the improvement of oxidation resistance is discussed in terms of microstructural evolution.

Recently Organic-inorganic halide perovskite (OIHP) solar cells have become one of the most promising next-generation photovoltaic materials due to their excellent electrical and optical properties. Formamidinium lead triiodide (HC(NH2)2PbI3, FAPbI3) exhibits the narrowest band gap (~1.45 eV) among Pb-based halide perovskites, which is closer to Shockley-Queisser limit than that (~1.55 eV) of Methylammonium Lead Iodide (CH3NH3PbI3, MAPbI3). Therefore, FAPbI3 has been widely adopted for recently developed highly efficient photovoltaic cells. In addition, FAPbI3 has better stability than MAPbI3, which can be easily decomposed at a high temperature or humid environment. The spin-coating has been widely adopted to make FAPbI3-based solar cells, whereas the large-area coating technologies have not been extensively studied, yet. This study presents the compositional engineering research on the polymorph control of formamidinium-based lead halide perovskites for the large-area film coating. The polymorph control of FAPbI3 has been one of the most important issues since its first appearance in photovoltaic applications. Non-perovskite structure (δ-FAPbI3) is thermodynamically more stable than the three-dimensional perovskite structure (α-FAPbI3). We adopted the shear coating method to make perovskite layers and controlled the polymorphism through A-site mixing. MA, commonly used A-site molecule, is excluded because MA can be a weak spot at the humid condition. Br mixing is not applied due to the photo-induced phase separation issue. Our results reveal that double-cation mixing (Cs-FA or Rb-FA) is not enough and triple-cation mixing (Rb-Cs-FA) cannot be avoided to make robust α-FAPbI3 for the shear coating process. We present the ternary phase diagram of (Rb-CS-FA)PbI3 to show the process window based on the XRD analysis of mixed perovskite films. The photovoltaic cell shows 15.8% power conversion efficiency (PCE) at the best compositional mixing point, which is the best PCE for FA-based perovskite solar cells fabricated by shear coating method without MA-Br mixing.

Additional file 1: Figure S1. InP(111)B “nanoisland” reference substrate, treated with high temperature deposition of InP nanostructure, exhibiting preferred lateral growth to vertical growth. Figure S2. Effect of excitation power on Raman spectra of InP/InAs/InP nanopillar and nanocone for two substrate tilting angles (0 and 30 degrees).

This work was supported by NSF Grants DMR 1207213, DMR1400432, and EFRI-2DARE 1433490, and by LEAST-STARnet, a Semiconductor Research Corporation program, sponsored by MARCO and DARPA and by SRC NRI SWAN. This work was also supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (Nos. NRF-2018R1C1B5085644 and NRF-2019R1A2B5B02070657).

Metal nanowire networks represent a promising candidate for the rapid fabrication of transparent electrodes with high transmission and low sheet-resistance values at very low deposition temperatures. A commonly encountered challenge in the formation of conductive nanowire electrodes is establishing high-quality electronic contact between nanowires to facilitate long-range current transport through the network. A new system involving nanowire ligand removal and replacement with a semiconducting sol-gel tin oxide matrix has enabled the fabrication of high-performance transparent electrodes at dramatically reduced temperatures with minimal need for post-deposition treatment.

Sn–Ag alloys are gaining importance among microelectronics manufacturers because of their potential benefits, e.g., low melting point, excellent wetting to common metallic substrates, and superior mechanical properties required for microelectronic packaging devices. In this work, Sn–Ag alloy was co-deposited from acidic citric acid bath on copper substrates. The plating solution was composed of SnSO4, Ag2SO4, thiourea, and citric acid as a supporting electrolyte. Further, the influence of current density on the Ag content of the coatings was studied. The results indicate that the citric acid bath produces bright Sn–Ag deposits over a wide range of current densities. The grains of the deposits obtained were bigger at lower current densities (10–30 mA cm−2) and become finer at higher current densities (40–50 mA cm−2). Initially, the coatings were very hard and become soft as the current density increases gradually due to the decreased amount of Ag in the deposit which modified the coating solderability.

Metal halide perovskites (MHPs) are one of the promising candidates for next-generation photovoltaic materials. Since the Miyasa group first adopt methylammonium lead tri-iodides as a sensitizer of dye-sensitized solar cells, the efficiency of MHP solar cells has improved at an unprecedented speed. According to the recent report of national renewable energy laboratory, the certified power conversion efficiency (PCE) of MHP solar cells exceeded 23%. However, stability and toxicity are primary concerns for MHP solar cell commercialization. Among various efforts to develop Pb-free perovskite solar cells, Sn-based materials have shown the PCE. However, the stability of Sn-based perovskites is worse than Pb-based solar cells, and the multivalent features of Sn are considered to be the origin of the unstable performance. Compositional engineering and additive control can be the effective ways to develop highly stable and efficient Pb-free perovskite solar cells. This study presents the effects of compositional engineering and various additives on the stabilization of Pb-free MHP materials via ab initio thermodynamics calculations. The concept of the ‘anti-stabilizer’ for the proper selection of the preferred phase is suggested by our previous report[1]. We present that the anti-stabilizing concept can be successfully applied to stabilize the proper band gap polymorph of black CsSnI3[2]and Bi-based layered perovskites. Additionally, the roles of additives including small alkali metal interstitials are discussed concerning thermodynamics. [1] J. Jeon, T. Eom, E. Lee, S. Kim, S. Kim, K.-H. Hong, H. Kim, J. Phys. Chem. C 121 (2017) 9508–9515. [2] J.H. Heo, J. Kim, H. Kim, S.H. Moon, S.H. Im, K.-H. Hong, J. Phys. Chem. Lett. 9 (2018) 6024–6031.

We report the growth of vertical -oriented InAsxP1−x (0.11 ≤ x ≤ 0.27) nanowires via metal-organic chemical vapor deposition in the presence of indium droplets as catalysts on InP(111)B substrates at 375 °C. Trimethylindium, tertiarybutylphosphine, and tertiarybutylarsine are used as the precursors, corresponding to P/In and As/In molar ratios of 29 and 0.01, respectively. The as-grown nanowire growth morphologies, crystallinity, composition, and optical characteristics are determined using a combination of scanning and transmission electron microscopies, electron diffraction, and X-ray photoelectron, energy dispersive X-ray, and Raman spectroscopies. We find that the InAsxP1−x nanowires are tapered with narrow tops, wider bases, and In-rich In-As alloy tips, characteristic of vapor-liquid-solid process. The wires exhibit a mixture of zinc blende and wurtzite crystal structures and a high density of structural defects such as stacking faults and twins. Our results suggest that the incorporation of As into InP wires decreases with increasing substrate temperature. The Raman spectra obtained from the In(As)P nanowires reveal a red-shift and lower intensity of longitudinal optical mode relative to both InP nanowires and InP(111)B bulk, due to the incorporation of As into the InP matrix. Electronic supplementary material The online version of this article (doi:10.1186/s11671-016-1427-4) contains supplementary material, which is available to authorized users.

Although silver nanowire meshes have already demonstrated sheet resistance and optical transmittance comparable to those of sputter-deposited indium tin oxide thin films, other critical issues including surface morphology, mechanical adhesion and flexibility have to be addressed before widely employing silver nanowire networks as transparent conductors in optoelectronic devices. Here, we demonstrate the efficacy of low temperature solution-processed flexible metal nanowire networks embedded in a conductive metal oxide nanoparticle matrix as transparent conductors, and investigate their microstructural, optoelectronic, and mechanical properties in attempting to resolve nearly all of the technological issues imposed on silver nanowire networks. Surrounding silver nanowires by conductive indium tin oxide nanoparticles offers low wire to wire junction resistance, smooth surface morphology, and excellent mechanical adhesion and flexibility while maintaining the high transmittance and the low sheet resistance. In addition, we discuss the relationship between sheet resistance and transmittance in the silver nanowire composite transparent conductors and their maximum achievable transmittance. Although we have selected silver nanowires and indium tin oxide nanoparticle matrix as demonstration materials, we anticipate that various metal nanowire meshes embedded in various conductive metal oxide nanoparticle matrices can effectively serve as transparent conductors for a wide variety of optoelectronic devices owing to their superior performance, simple, cost-effective, and gentle processing.

In this paper, we describe the fabrication of 3.5-inch QCIF active matrix organic light emitting display (AMOLED) panels driven by thin film transistors, which are produced by an ultra-low-temperature polycrystalline silicon process on plastic substrates. The over all processing scheme and technical details are discussed from the viewpoint of mechanical stability and display performance. New ideas, such as a new triple-layered metal gate structure to lower leakage current and organic layers for electrical passivation and stress reduction are highlighted. The operation of a 3.5-inch QCIF AMOLED is also demonstrated.

We present, for the first time, a prototype active-matrix field emission display (AMFED) in which an amorphous silicon thin-film transistor (a-Si TFT) and a molybdenumtip field emitter array (Mo-tip FEA) were monolithically integrated on a glass substrate for a novel active -matrix cathode (AMC) plate. The fabricated AMFED showed good display images with a low-voltage scan and data signals irrespective of a high voltage for field emissions. We introduced a light shield layer of metal into our AMC to reduce the photo leakage and back channel currents of the a-Si TFT. We designed the light shield to act as a focusing grid to focus emitted electron beams from the AMC onto the corresponding anode pixel. The thin film depositions in the a-Si TF Ts were performed at a high temperature of above 360 ° C to guarantee the vacuum packaging of the AMC and anode plates. We also developed a novel wet etching process for n + -doped a-Si etching with high etch selectivity to intrinsic a-Si and used it in the fabrication of an inverted stagger TFT with a very thin active layer. The developed a-Si TFTs performed well enough to be used as control devices for AMCs. The gate bias of the a-Si TFTs well controlled the field emission currents of the AMC plates. The AMFED with these AMC plates showed lowvoltage matrix addressing, good stability and reliability of field emission, and good light emissions from the anode plate with phosphors.

We have designed and monolithically integrated amorphous silicon thin-film transistor (a-Si TFT) with Mo-tip field emitter arrays (FEAs) on glass substrate for active-matrix cathodes (AMCs) in field-emission display (FED) application. In our AMCs, a light shield layer of metal was introduced to reduce the photo leakage and back channel currents of a-Si TFT. The light shield was designed to have the role of focusing grid to focus emitted electron beams from the AMC on the corresponding anode pixel by forming it around the Mo-tip FEAs as well as above the a-Si TFT. The thin film depositions in a-Si TFTs were performed at a high temperature of above 360/spl deg/C to guarantee the postvacuum packaging process of cathode and anode plates in FED. Also, a novel wet etching process was developed for n/sup +/-doped-a-Si etching with high etch selectivity to intrinsic a-Si and good etch controllability and was used in the fabrication of inverted stagger TFT with a very thin active layer. The developed a-Si TFTs had good enough performance to be used as control devices for AMCs with Mo-tip emitters. The fabricated AMCs exhibited very effective aging process for field emitters.

Amorphous silicon thin‐film transistors (a‐Si TFTs) were incorporated into Mo‐tip‐based triode‐type field emitters and diode‐type ones of carbon nanotubes for an active‐matrix cathode (AMC) plate of field emission displays. Also, we developed a novel surface‐treatment process for the Mo‐tip fabrication, which gleatly enhanced in the stability of field emission. The field emission currents of AMC plates on glass substrate were well controlled by the gate bias of a‐Si TFTs. Active‐matrix field emission displays (AMFEDs) with these AMC plates were demonstrated in a vacuum chamber, showing low‐voltage matrix addressing, good stability and reliability of field emission, and highly uniform light emissions from the anode plate with phosphors. The optimum design of AMFEDs including a‐Si TFTs and a new light shield/focusing grid is discussed.

ZnO:Al thin films have been widely used as transparent conductors in variety of optoelectronic devices including CuInGaSe2 thin film solar cells. However, high cost sputtering process has been typically employed to prepare high quality ZnO:Al thin fil simultaneously having both high optical transmittance and low sheet resistance. In this study, we present the ZnO:Al thin films prepared by the chemical bath deposition using NH4OH-based aqueous solution on seeded glass substrates. We also report their properties and application to CuInGaSe2 thin film solar cells as a top transparent electrode. A seed layer on glass substrate was prepared by spin-coating of ZnO nanoparticles with size of a few tens of nanometer. For the chemical bath deposition process, ZnO powder was dissolved in NH4OH-based aqueous solution and un-dissolved ZnO powder was removed by transferring the ZnO solution through 1 um filter. Retrograde solubility of ZnO in NH4OH-based aqueous solution allows us to deposit ZnO thin films by raising temperature of the bath from room temperature to 80 oC. To obtain compact film by enhancing growth rate of crystal in lateral direction, a certain amount (~0.5-2 mM) of ammonium citrate was added into the bath. A various amount of Al(NO3)3 was added into the bath as a aluminum source to maximize electrical conductivity by forming Al substitution in Zn site. The prepared ZnO:Al films were irradiated by UV for 1 min. Optimized ZnO:Al films showed (0002) preferred orientation, optical transmittance of 90% and sheet resistance of 75 ohm/sq. Furthermore, the prepared ZnO:Al thin film was successfully implanted to CIGS thin film solar cells as a top electrode showing power conversion efficiency of 12.5% comparable to the performance (~13.7%) of CIGS solar cells having a sputter-deposited ZnO:Al film transparent electrode.

We developed a dispersal method for multi-walled carbon nanotubes (MWCNTs) that allows quantitative assessment of dispersion on pro-fibrogenic responses in tissue culture cells as well as in mouse lung. Here we demonstrate that the dispersal of as-prepared (AP), purified (PD), and carboxylated (COOH) MWCNTs by bovine serum albumin (BSA) and dipalmitoylphosphatidylcholine (DPPC) influences TGF-β1, PDGF-AA and IL-1β production in vitro and in vivo. These biomarkers were chosen based on their synergy in promoting fibrogenesis and cellular communication in the epithelial-mesenchymal cell trophic unit in the lung. The effect of dispersal was most noticeable in AP- and PD-MWCNTs, which are more hydrophobic and unstable in aqueous buffers than hydrophilic COOH-MWCNTs. Well-dispersed AP- and PD-MWCNTs were readily taken up by BEAS-2B, THP-1 cells and alveolar macrophages (AM), and induced more prominent TGF-β1 and IL-1β production in vitro as well as TGF-β1, IL-1β and PDGF-AA production in vivo than non-dispersed tubes. Moreover, there was good agreement between the pro-fibrogenic responses in vitro and in vivo as well as the ability of dispersed tubes to generate granulomatous inflammation and fibrosis in airways. Tube dispersal also elicited more robust IL-1β production in THP-1 cells. While COOH-MWCNTs were poorly taken up in BEAS-2B and induced little TGF-β1 production, they were bio-processed by AM and induced less prominent collagen deposition at sites of non-granulomatous inflammation in the alveolar region. Taken together, these results indicate that the dispersal state of MWCNTs affects pro-fibrogenic cellular responses that correlate with the extent of pulmonary fibrosis and are of potential use to predict pulmonary toxicity.