Publications by authors named "BoFei Liu"

18 Publications

  • Page 1 of 1

Integrated cooling (i-Cool) textile of heat conduction and sweat transportation for personal perspiration management.

Nat Commun 2021 Oct 21;12(1):6122. Epub 2021 Oct 21.

Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA.

Perspiration evaporation plays an indispensable role in human body heat dissipation. However, conventional textiles tend to focus on sweat removal and pay little attention to the basic thermoregulation function of sweat, showing limited evaporation ability and cooling efficiency in moderate/profuse perspiration scenarios. Here, we propose an integrated cooling (i-Cool) textile with unique functional structure design for personal perspiration management. By integrating heat conductive pathways and water transport channels decently, i-Cool exhibits enhanced evaporation ability and high sweat evaporative cooling efficiency, not merely liquid sweat wicking function. In the steady-state evaporation test, compared to cotton, up to over 100% reduction in water mass gain ratio, and 3 times higher skin power density increment for every unit of sweat evaporation are demonstrated. Besides, i-Cool shows about 3 °C cooling effect with greatly reduced sweat consumption than cotton in the artificial sweating skin test. The practical application feasibility of i-Cool design principles is well validated based on commercial fabrics. Owing to its exceptional personal perspiration management performance, we expect the i-Cool concept can provide promising design guidelines for next-generation perspiration management textiles.
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http://dx.doi.org/10.1038/s41467-021-26384-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8531342PMC
October 2021

Miro1 provides neuroprotection via the mitochondrial trafficking pathway in a rat model of traumatic brain injury.

Brain Res 2021 Oct 9;1773:147685. Epub 2021 Oct 9.

Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, China.

The outer mitochondrial membrane protein mitochondrial Rho-GTPase 1 (Miro1) is known to be involved in the regulation of mitochondrial transport required for neuronal protection. Previous reports established that disruption of Miro1-dependent mitochondrial movement could result in nervous system diseases such as Parkinson's disease and Alzheimer's disease. This study was designed to explore the expression and mechanisms of Miro1 in secondary brain injury after traumatic brain injury (TBI). A total of 115 male Sprague Dawley rats were used in the weight-drop TBI rat model, and Miro1 in vivo knockdown was performed 24 h before TBI modeling by treatment with Miro1 short-interfering RNA. Real-time polymerase chain reaction, western blot, immunofluorescence, adenosine triphosphate (ATP) level assay, neuronal apoptosis, brain water content measurement, and neurological score analyses were carried out. Our results showed that the mRNA and protein levels of Miro1 were increased after TBI and co-localized with neurons and astrocytes in the peri-injury cortex. Moreover, Miro1 knockdown further exacerbated neuronal apoptosis, brain edema, and neurological deficits at 48 h after TBI, accompanied by impaired mitochondrial transport, reduction of mitochondria number and energy deficiency. Additionally, the apoptosis-related factors Bax upregulation and Bcl-2 downregulation as Miro1 knockdown after TBI implied that antiapoptotic effects on neuroprotection of Miro1, which were verified by the Fluoro-Jade C (FJC) staining and TUNEL staining. In conclusion, these findings suggest that Miro1 probably plays a neuroprotective role against secondary brain injury through the mitochondria trafficking pathway, suggesting that enhancing Miro1 might be a new strategy for the treatment of TBI.
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http://dx.doi.org/10.1016/j.brainres.2021.147685DOI Listing
October 2021

Electrotunable liquid sulfur microdroplets.

Nat Commun 2020 Jan 30;11(1):606. Epub 2020 Jan 30.

Department of Materials Science and Engineering, Stanford University, Stanford, CA, 94305, USA.

Manipulating liquids with tunable shape and optical functionalities in real time is important for electroactive flow devices and optoelectronic devices, but remains a great challenge. Here, we demonstrate electrotunable liquid sulfur microdroplets in an electrochemical cell. We observe electrowetting and merging of sulfur droplets under different potentiostatic conditions, and successfully control these processes via selective design of sulfiphilic/sulfiphobic substrates. Moreover, we employ the electrowetting phenomena to create a microlens based on the liquid sulfur microdroplets and tune its characteristics in real time through changing the shape of the liquid microdroplets in a fast, repeatable, and controlled manner. These studies demonstrate a powerful in situ optical battery platform for unraveling the complex reaction mechanism of sulfur chemistries and for exploring the rich material properties of the liquid sulfur, which shed light on the applications of liquid sulfur droplets in devices such as microlenses, and potentially other electrotunable and optoelectronic devices.
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http://dx.doi.org/10.1038/s41467-020-14438-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6992759PMC
January 2020

Electrochemical generation of liquid and solid sulfur on two-dimensional layered materials with distinct areal capacities.

Nat Nanotechnol 2020 Mar 27;15(3):231-237. Epub 2020 Jan 27.

Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA.

It has recently been shown that sulfur, a solid material in its elementary form S, can stay in a supercooled state as liquid sulfur in an electrochemical cell. We establish that this newly discovered state could have implications for lithium-sulfur batteries. Here, through in situ studies of electrochemical sulfur generation, we show that liquid (supercooled) and solid elementary sulfur possess very different areal capacities over the same charging period. To control the physical state of sulfur, we studied its growth on two-dimensional layered materials. We found that on the basal plane, only liquid sulfur accumulates; by contrast, at the edge sites, liquid sulfur accumulates if the thickness of the two-dimensional material is small, whereas solid sulfur nucleates if the thickness is large (tens of nanometres). Correlating the sulfur states with their respective areal capacities, as well as controlling the growth of sulfur on two-dimensional materials, could provide insights for the design of future lithium-sulfur batteries.
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http://dx.doi.org/10.1038/s41565-019-0624-6DOI Listing
March 2020

Synergistic enhancement of electrocatalytic CO reduction to C oxygenates at nitrogen-doped nanodiamonds/Cu interface.

Nat Nanotechnol 2020 Feb 6;15(2):131-137. Epub 2020 Jan 6.

Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA.

To date, effective control over the electrochemical reduction of CO to multicarbon products (C ≥ 2) has been very challenging. Here, we report a design principle for the creation of a selective yet robust catalytic interface for heterogeneous electrocatalysts in the reduction of CO to C oxygenates, demonstrated by rational tuning of an assembly of nitrogen-doped nanodiamonds and copper nanoparticles. The catalyst exhibits a Faradaic efficiency of ~63% towards C oxygenates at applied potentials of only -0.5 V versus reversible hydrogen electrode. Moreover, this catalyst shows an unprecedented persistent catalytic performance up to 120 h, with steady current and only 19% activity decay. Density functional theory calculations show that CO binding is strengthened at the copper/nanodiamond interface, suppressing CO desorption and promoting C production by lowering the apparent barrier for CO dimerization. The inherent compositional and electronic tunability of the catalyst assembly offers an unrivalled degree of control over the catalytic interface, and thereby the reaction energetics and kinetics.
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http://dx.doi.org/10.1038/s41565-019-0603-yDOI Listing
February 2020

Fast lithium growth and short circuit induced by localized-temperature hotspots in lithium batteries.

Nat Commun 2019 05 6;10(1):2067. Epub 2019 May 6.

Department of Materials Science and Engineering, Stanford University, Stanford, CA, 94305, USA.

Fast-charging and high-energy-density batteries pose significant safety concerns due to high rates of heat generation. Understanding how localized high temperatures affect the battery is critical but remains challenging, mainly due to the difficulty of probing battery internal temperature with high spatial resolution. Here we introduce a method to induce and sense localized high temperature inside a lithium battery using micro-Raman spectroscopy. We discover that temperature hotspots can induce significant lithium metal growth as compared to the surrounding lower temperature area due to the locally enhanced surface exchange current density. More importantly, localized high temperature can be one of the factors to cause battery internal shorting, which further elevates the temperature and increases the risk of thermal runaway. This work provides important insights on the effects of heterogeneous temperatures within batteries and aids the development of safer batteries, thermal management schemes, and diagnostic tools.
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http://dx.doi.org/10.1038/s41467-019-09924-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6502817PMC
May 2019

Direct electrochemical generation of supercooled sulfur microdroplets well below their melting temperature.

Proc Natl Acad Sci U S A 2019 01 2;116(3):765-770. Epub 2019 Jan 2.

Department of Physics, Stanford University, Stanford, CA 94305;

Supercooled liquid sulfur microdroplets were directly generated from polysulfide electrochemical oxidation on various metal-containing electrodes. The sulfur droplets remain liquid at 155 °C below sulfur's melting point ( = 115 °C), with fractional supercooling change ( - )/ larger than 0.40. light microscopy captured the rapid merging and shape relaxation of sulfur droplets, indicating their liquid nature. Micropatterned electrode and electrochemical current allow precise control of the location and size of supercooled microdroplets, respectively. Using this platform, we initiated and observed the rapid solidification of supercooled sulfur microdroplets upon crystalline sulfur touching, which confirms supercooled sulfur's metastability at room temperature. In addition, the formation of liquid sulfur in electrochemical cell enriches lithium-sulfur-electrolyte phase diagram and potentially may create new opportunities for high-energy Li-S batteries.
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http://dx.doi.org/10.1073/pnas.1817286116DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6338843PMC
January 2019

Reversible and selective ion intercalation through the top surface of few-layer MoS.

Nat Commun 2018 12 11;9(1):5289. Epub 2018 Dec 11.

Department of Materials Science and Engineering, Stanford University, Stanford, California, 94305, USA.

Electrochemical intercalation of ions into the van der Waals gap of two-dimensional (2D) layered materials is a promising low-temperature synthesis strategy to tune their physical and chemical properties. It is widely believed that ions prefer intercalation into the van der Waals gap through the edges of the 2D flake, which generally causes wrinkling and distortion. Here we demonstrate that the ions can also intercalate through the top surface of few-layer MoS and this type of intercalation is more reversible and stable compared to the intercalation through the edges. Density functional theory calculations show that this intercalation is enabled by the existence of natural defects in exfoliated MoS flakes. Furthermore, we reveal that sealed-edge MoS allows intercalation of small alkali metal ions (e.g., Li and Na) and rejects large ions (e.g., K). These findings imply potential applications in developing functional 2D-material-based devices with high tunability and ion selectivity.
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http://dx.doi.org/10.1038/s41467-018-07710-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6290021PMC
December 2018

MicroRNA-27a alleviates LPS-induced acute lung injury in mice via inhibiting inflammation and apoptosis through modulating TLR4/MyD88/NF-κB pathway.

Cell Cycle 2018 19;17(16):2001-2018. Epub 2018 Sep 19.

a Department of Critial Care Medicine , Zhongshan Hospital, Fudan University , Shanghai China.

Acute lung injury (ALI) is a critical clinical condition with a high mortality rate, characterized with excessive uncontrolled inflammation and apoptosis. Recently, microRNAs (miRNAs) have been found to play crucial roles in the amelioration of various inflammation-induced diseases, including ALI. However, it remains unknown the biological function and regulatory mechanisms of miRNAs in the regulation of inflammation and apoptosis in ALI. The aim of this study is to identify and evaluate the potential role of miRNAs in ALI and reveal the underlying molecular mechanisms of their effects. Here, we analyzed microRNA expression profiles in lung tissues from LPS-challenged mice using miRNA microarray. Because microRNA-27a (miR-27a) was one of the miRNAs being most significantly downregulated, which has an important role in regulation of inflammation, we investigated its function. Overexpression of miR-27a by agomir-27a improved lung injury, as evidenced by the reduced histopathological changes, lung wet/dry (W/D) ratio, lung microvascular permeability and apoptosis in the lung tissues, as well as ameliorative survival of ALI mice. This was accompanied by the alleviating of inflammation, such as the reduced total BALF cell and neutrophil counts, decreased levels of tumor necrosis factor alpha (TNF-α), interleukin-1 (IL-6) interleukin-1β (IL-1β) and myeloperoxidase (MPO) activity in BAL fluid. Toll-like receptor 4 (TLR4), an important regulator of the nuclear factor kappa-B (NF-κB) signaling pathway, was identified as a novel target of miR-27a in RAW264.7 cells. Furthermore, our results showed that LPS stimulation increased the expression of MyD88 and NF-κB p65 (p-p65), but inhibited the expression of inhibitor of nuclear factor-κB-α (IκB-α), suggesting the activation of NF-κB signaling pathway. Further investigations revealed that agomir-miR-27a reversed the promoting effect of LPS on NF-κB signaling pathway. The results here suggested that miR-27a alleviates LPS-induced ALI in mice via reducing inflammation and apoptosis through blocking TLR4/MyD88/NF-κB activation.
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http://dx.doi.org/10.1080/15384101.2018.1509635DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6260216PMC
December 2019

Carbon nanotube bundles with tensile strength over 80 GPa.

Nat Nanotechnol 2018 07 14;13(7):589-595. Epub 2018 May 14.

Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology, Department of Chemical Engineering, Tsinghua University, Beijing, China.

Carbon nanotubes (CNTs) are one of the strongest known materials. When assembled into fibres, however, their strength becomes impaired by defects, impurities, random orientations and discontinuous lengths. Fabricating CNT fibres with strength reaching that of a single CNT has been an enduring challenge. Here, we demonstrate the fabrication of CNT bundles (CNTBs) that are centimetres long with tensile strength over 80 GPa using ultralong defect-free CNTs. The tensile strength of CNTBs is controlled by the Daniels effect owing to the non-uniformity of the initial strains in the components. We propose a synchronous tightening and relaxing strategy to release these non-uniform initial strains. The fabricated CNTBs, consisting of a large number of components with parallel alignment, defect-free structures, continuous lengths and uniform initial strains, exhibit a tensile strength of 80 GPa (corresponding to an engineering tensile strength of 43 GPa), which is far higher than that of any other strong fibre.
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http://dx.doi.org/10.1038/s41565-018-0141-zDOI Listing
July 2018

An Aqueous Inorganic Polymer Binder for High Performance Lithium-Sulfur Batteries with Flame-Retardant Properties.

ACS Cent Sci 2018 Feb 14;4(2):260-267. Epub 2018 Feb 14.

Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States.

Lithium-sulfur (Li-S) batteries are regarded as promising next-generation high energy density storage devices for both portable electronics and electric vehicles due to their high energy density, low cost, and environmental friendliness. However, there remain some issues yet to be fully addressed with the main challenges stemming from the ionically insulating nature of sulfur and the dissolution of polysulfides in electrolyte with subsequent parasitic reactions leading to low sulfur utilization and poor cycle life. The high flammability of sulfur is another serious safety concern which has hindered its further application. Herein, an aqueous inorganic polymer, ammonium polyphosphate (APP), has been developed as a novel multifunctional binder to address the above issues. The strong binding affinity of the main chain of APP with lithium polysulfides blocks diffusion of polysulfide anions and inhibits their shuttling effect. The coupling of APP with Li ion facilitates ion transfer and promotes the kinetics of the cathode reaction. Moreover, APP can serve as a flame retardant, thus significantly reducing the flammability of the sulfur cathode. In addition, the aqueous characteristic of the binder avoids the use of toxic organic solvents, thus significantly improving safety. As a result, a high rate capacity of 520 mAh g at 4 C and excellent cycling stability of ∼0.038% capacity decay per cycle at 0.5 C for 400 cycles are achieved based on this binder. This work offers a feasible and effective strategy for employing APP as an efficient multifunctional binder toward building next-generation high energy density Li-S batteries.
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http://dx.doi.org/10.1021/acscentsci.7b00569DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5833002PMC
February 2018

Spatially controlled doping of two-dimensional SnS through intercalation for electronics.

Nat Nanotechnol 2018 04 26;13(4):294-299. Epub 2018 Feb 26.

Department of Material Science and Engineering, Stanford University, Stanford, CA, USA.

Doped semiconductors are the most important building elements for modern electronic devices . In silicon-based integrated circuits, facile and controllable fabrication and integration of these materials can be realized without introducing a high-resistance interface. Besides, the emergence of two-dimensional (2D) materials enables the realization of atomically thin integrated circuits. However, the 2D nature of these materials precludes the use of traditional ion implantation techniques for carrier doping and further hinders device development . Here, we demonstrate a solvent-based intercalation method to achieve p-type, n-type and degenerately doped semiconductors in the same parent material at the atomically thin limit. In contrast to naturally grown n-type S-vacancy SnS, Cu intercalated bilayer SnS obtained by this technique displays a hole field-effect mobility of ~40 cm Vs, and the obtained Co-SnS exhibits a metal-like behaviour with sheet resistance comparable to that of few-layer graphene . Combining this intercalation technique with lithography, an atomically seamless p-n-metal junction could be further realized with precise size and spatial control, which makes in-plane heterostructures practically applicable for integrated devices and other 2D materials. Therefore, the presented intercalation method can open a new avenue connecting the previously disparate worlds of integrated circuits and atomically thin materials.
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http://dx.doi.org/10.1038/s41565-018-0069-3DOI Listing
April 2018

In Situ Investigation on the Nanoscale Capture and Evolution of Aerosols on Nanofibers.

Nano Lett 2018 02 9;18(2):1130-1138. Epub 2018 Jan 9.

Department of Materials Science and Engineering, Stanford University , Stanford, California 94305, United States.

Aerosol-induced haze problem has become a serious environmental concern. Filtration is widely applied to remove aerosols from gas streams. Despite classical filtration theories, the nanoscale capture and evolution of aerosols is not yet clearly understood. Here we report an in situ investigation on the nanoscale capture and evolution of aerosols on polyimide nanofibers. We discovered different capture and evolution behaviors among three types of aerosols: wetting liquid droplets, nonwetting liquid droplets, and solid particles. The wetting droplets had small contact angles and could move, coalesce, and form axisymmetric conformations on polyimide nanofibers. In contrast, the nonwetting droplets had a large contact angle on polyimide nanofibers and formed nonaxisymmetric conformations. Different from the liquid droplets, the solid particles could not move along the nanofibers and formed dendritic structures. This study provides an important insight for obtaining a deep understanding of the nanoscale capture and evolution of aerosols and benefits future design and development of advanced filters.
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http://dx.doi.org/10.1021/acs.nanolett.7b04673DOI Listing
February 2018

Strong texturing of lithium metal in batteries.

Proc Natl Acad Sci U S A 2017 11 30;114(46):12138-12143. Epub 2017 Oct 30.

Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305;

Lithium, with its high theoretical specific capacity and lowest electrochemical potential, has been recognized as the ultimate negative electrode material for next-generation lithium-based high-energy-density batteries. However, a key challenge that has yet to be overcome is the inferior reversibility of Li plating and stripping, typically thought to be related to the uncontrollable morphology evolution of the Li anode during cycling. Here we show that Li-metal texturing (preferential crystallographic orientation) occurs during electrochemical deposition, which governs the morphological change of the Li anode. X-ray diffraction pole-figure analysis demonstrates that the texture of Li deposits is primarily dependent on the type of additive or cross-over molecule from the cathode side. With adsorbed additives, like LiNO and polysulfide, the lithium deposits are strongly textured, with Li (110) planes parallel to the substrate, and thus exhibit uniform, rounded morphology. A growth diagram of lithium deposits is given to connect various texture and morphology scenarios for different battery electrolytes. This understanding of lithium electrocrystallization from the crystallographic point of view provides significant insight for future lithium anode materials design in high-energy-density batteries.
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http://dx.doi.org/10.1073/pnas.1708224114DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5699048PMC
November 2017

Revealing the Cell-Material Interface with Nanometer Resolution by Focused Ion Beam/Scanning Electron Microscopy.

ACS Nano 2017 08 21;11(8):8320-8328. Epub 2017 Jul 21.

Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator , Menlo Park, California 94025, United States.

The interface between cells and nonbiological surfaces regulates cell attachment, chronic tissue responses, and ultimately the success of medical implants or biosensors. Clinical and laboratory studies show that topological features of the surface profoundly influence cellular responses; for example, titanium surfaces with nano- and microtopographical structures enhance osteoblast attachment and host-implant integration as compared to a smooth surface. To understand how cells and tissues respond to different topographical features, it is of critical importance to directly visualize the cell-material interface at the relevant nanometer length scale. Here, we present a method for in situ examination of the cell-to-material interface at any desired location, based on focused ion beam milling and scanning electron microscopy imaging to resolve the cell membrane-to-material interface with 10 nm resolution. By examining how cell membranes interact with topographical features such as nanoscale protrusions or invaginations, we discovered that the cell membrane readily deforms inward and wraps around protruding structures, but hardly deforms outward to contour invaginating structures. This asymmetric membrane response (inward vs outward deformation) causes the cleft width between the cell membrane and the nanostructure surface to vary by more than an order of magnitude. Our results suggest that surface topology is a crucial consideration for the development of medical implants or biosensors whose performances are strongly influenced by the cell-to-material interface. We anticipate that the method can be used to explore the direct interaction of cells/tissue with medical devices such as metal implants in the future.
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http://dx.doi.org/10.1021/acsnano.7b03494DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5806611PMC
August 2017

Catalytic oxidation of Li2S on the surface of metal sulfides for Li-S batteries.

Proc Natl Acad Sci U S A 2017 01 17;114(5):840-845. Epub 2017 Jan 17.

Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305;

Polysulfide binding and trapping to prevent dissolution into the electrolyte by a variety of materials has been well studied in Li-S batteries. Here we discover that some of those materials can play an important role as an activation catalyst to facilitate oxidation of the discharge product, LiS, back to the charge product, sulfur. Combining theoretical calculations and experimental design, we select a series of metal sulfides as a model system to identify the key parameters in determining the energy barrier for LiS oxidation and polysulfide adsorption. We demonstrate that the LiS decomposition energy barrier is associated with the binding between isolated Li ions and the sulfur in sulfides; this is the main reason that sulfide materials can induce lower overpotential compared with commonly used carbon materials. Fundamental understanding of this reaction process is a crucial step toward rational design and screening of materials to achieve high reversible capacity and long cycle life in Li-S batteries.
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http://dx.doi.org/10.1073/pnas.1615837114DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5293031PMC
January 2017

Broadband light trapping based on periodically textured ZnO thin films.

Nanoscale 2015 Jun;7(21):9816-24

Institute of Photo Electronics thin Film Devices and Technology of Nankai University, Key Laboratory of Photoelectronic Thin Film Devices and Technology, Tianjin 300071, P. R. China.

Transparent conductive front electrodes (TCFEs) deployed in photovoltaic devices have been extensively studied for their significance in transporting carriers, coupling and trapping the incident photons in high-performing solar cells. The trade-off between the light-transmission, electrical, and scattering properties for TCFEs to achieve a broadband improvement in light absorption in solar cells while maintaining a high electrical performance has become the key issue to be tackled. In this paper, we employ self-assembled polystyrene (PS) spheres based on a sauna-like method as a template, followed by a double-layer deposition and then successfully fabricate highly-transparent, well-conductive, and large-scale periodically-textured ZnO TCFEs with broadband light trapping properties. A sheet resistance below 15 Ω sq(-1) was achieved for the periodically-textured ZnO TCFEs, with a concomitant average transmission of 81% (including the glass substrate) in the 400-1100 nm spectral range, a haze improvement in a broadband spectral range, and a wider scattering angular domain. The proposed approach affords a promising alternative method to prepare periodically-textured TCFEs, which are essential for many optoelectronic device semiconductors, such as photovoltaic and display applications.
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http://dx.doi.org/10.1039/c5nr01528fDOI Listing
June 2015

Two-dimensional high efficiency thin-film silicon solar cells with a lateral light trapping architecture.

Sci Rep 2014 Aug 22;4:6169. Epub 2014 Aug 22.

Institute of Photo Electronics Thin Film Devices and Technology of Nankai University, Key Laboratory of Photoelectronic Thin Film Devices and Technology, Tianjin 300071, P. R. China.

Introducing light trapping structures into thin-film solar cells has the potential to enhance their solar energy harvesting as well as the performance of the cells; however, current strategies have been focused mainly on harvesting photons without considering the light re-escaping from cells in two-dimensional scales. The lateral out-coupled solar energy loss from the marginal areas of cells has reduced the electrical yield indeed. We therefore herein propose a lateral light trapping structure (LLTS) as a means of improving the light-harvesting capacity and performance of cells, achieving a 13.07% initial efficiency and greatly improved current output of a-Si:H single-junction solar cell based on this architecture. Given the unique transparency characteristics of thin-film solar cells, this proposed architecture has great potential for integration into the windows of buildings, microelectronics and other applications requiring transparent components.
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http://dx.doi.org/10.1038/srep06169DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4141247PMC
August 2014
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