Perovskite Nanoparticles

2D perovskite nanoparticles have a great potential for using in optoelectronic devices such as Solar Cells and Light Emitting Diodes within their tuneable optic and structural properties. In this chapter, it is aimed to express “relation between chemical structures and photo-physical behaviours of perovskite nanoparticles and milestones for their electronic applications”. Initially, general synthesis methods of perovskite nanoparticles have been explained. Furthermore, advantages and disadvantages of the methods have been discussed. After the synthesis, formation of 2D perovskite crystal and effects on shape factor, particle size and uniformity of perovskite have been explained in detail. Beside these, optic properties of luminescent perovskite nanoparticles have been summarized a long with spectral band tuning via size and composition changes. In addition, since their different optical properties and relatively more stable chemical structure under ambient conditions, a comprehensive compilation of opto-electronic applications of 2D perovskite nanoparticles have been prepared

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Improving power conversion efficiency by Light-Assisted annealing of triple cation perovskite layer in solar cell applications

Here we propose a light-assisted annealing (LA) method, for the formation of relatively larger and uniform grains of triple perovskite crystals with less nano-cracks in a custom designed LA system with a 250 mW/cm(2) halogen lamb. This method has the potential to reduce the annealing process time and energy consumption for mass production of perovskite solar cells (PSCs). For this purpose, initially, a series of perovskite films are prepared by LA method with various annealing time (1, 3, 5, 10, 15 min) to determine the optimum conditions. Subsequently, a comparative study is carried out for morphology, crystal structure and optic characterization. To assess the effect of the LA process on the structure and morphology of perovskite crystals, X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), and UV-Vis absorption spectroscopy techniques are carried out. Consequently, the photovoltaic application and stability tests are carried out with LA and TA films. A power conversion efficiency (PCE) of 17.86 % is achieved with an LA device annealed for 5 min (5-min-LA),while that of 16.74% is obtained with the standard device annealed on a hotplate for 60 min (60-min-TA).Presidency of Turkey, Department of Strategy and Budget [K121200-16DPT002]; Scientific and Technological Research Council of Turkey (TUBITAK) [218M940]This work was supported by Presidency of Turkey, Department of Strategy and Budget [2016 K121200-16DPT002, 2021]; Scientific and Technological Research Council of Turkey (TUBITAK) [218M940, 2021]

A quasi-incompressible and quasi-inextensible finite element analysis of fibrous soft biological tissues

The contribution presents anextensionandapplicationof a recently proposed finite element formulation for quasi-inextensible and quasi-incompressible finite hyperelasticity to fibrous soft biological tissues and touches in particular upon computational aspects thereof. In line with theoretical framework presented by Dal (Int J Numer Methods Eng 117:118-140, 2019), the mixed variational formulation is extended to two families of fibers as often encountered while dealing with fibrous tissues. Apart from that, the purelyEuleriansetting features the additive decomposition of the free energy function into volumetric, isotropic and anisotropic parts. The multiplicative split of the deformation gradient and all the outcomes thereof, e.g., unimodular invariants, are simply dispensed with in the three element formulations investigated, namelyQ1,Q1P0and the proposedQ1P0F0. For the quasi-incompressible response, theQ1P0element formulation is briefly outlined where the pressure-type Lagrange multiplier and its conjugate enter the variational formulation as an extended set of variables. Using the similar argumentation, an extended Hu-Washizu-type mixed variational potential is introduced where the volume averaged squares of fiber stretches and associated fiber stresses are additional field variables. The resulting finite element formulation calledQ1P0F0is very attractive as it is based on mean values of the additional field variables at element level through integration over the element domain in a preprocessing step, earning the model vast utilization areas. The proposed approach is examined through representative boundary value problems pertaining to fibrous biological tissues. For all the cases studied, the proposedQ1P0F0formulation elicits the most compliant mechanical response, thereby outperforming the standardQ1andQ1P0element formulations through mesh-refinement analyses. Results prompt further experimental investigations as to true deformation fields under biologically relevant loading conditions which would make the assessment ofQ1P0andQ1P0F0more based on physical grounds

Decreased surface defects and non-radiative recombination via the passivation of the halide perovskite film by 2-thiophenecarboxylic acid in triple-cation perovskite solar cells

Organic-inorganic lead halide perovskite solar cells (PSCs) attract great research interest due to their significant device performance and optoelectronic properties. However, reducing charge recombination and efficiency loss due to surface defects of the perovskite layer are still big issues to overcome for PSCs. Herein, we have employed a simple molecule, 2-thiophenecarboxylic acid (2TiCOOH), via post-treatment to passivate the uncoordinated Pb2+ on the perovskite film surface and improve the stability at the perovskite/Spiro-OMeTAD interface. The spectral results illustrate that the 2TiCOOH passivated devices exhibit higher carrier lifetime, charge extraction, and minimized defect induced recombination. Also, solar cells with 2TiCOOH show better charge collection, improved J(SC), FF, and outstanding power conversion efficiency (PCE). In addition, 2TiCOOH passivated solar cells show tremendously stable performance output with less than 1% PCE drop after 100 days. This work provides a facile surface passivation strategy for fabricating highly efficient, low cost, and stable perovskite solar cells, which can be used for large scale technology and commercialization.TUBITAK 1003 -Primary Subjects R&D Funding Program [218M940]; Presidency of the Republic of Turkey Strategy and Budget Department [2016K121200]D. A. K. and B. G. thank TUBITAK 1003 -Primary Subjects R&D Funding Program (218M940). The authors also thank the Presidency of the Republic of Turkey Strategy and Budget Department for laboratory infrastructure and substances (2016K121200)

Electrochemical double-layer supercapacitor using poly(methyl methacrylate) solid polymer electrolyte

3rd International Conference on Science and Engineering of Materials (ICSEM) -- JUL 19-21, 2019 -- Sharda Univ, Noida, INDIAWOS: 000523794000011The prime objective of the present article is to develop an efficient supercapacitor based on polymer electrolyte doped with salt. Solution cast technique was adopted to develop a solid polymer electrolyte of polymer poly(methyl methacrylate) (PMMA) as host polymer and salt potassium hydroxide (KOH) as a dopant. Incorporation of salt increases the amorphicity and assisted in conductivity enhancement. Moreover, doping of salt increases the overall conductivity of polymer electrolyte film. Electrochemical impedance spectroscopy reveals the enhancement in conductivity (four orders of magnitude) by salt doping. Fourier transform infrared shows the complexation and composite nature of films. Polarized optical microscopy shows the reduction in crystallinity, which is further confirmed by Differential scanning calorimetry. Fabricated electrochemical double-layer supercapacitor using maximum conducting polymer-salt electrolyte and symmetric carbon nanotubes electrodes shows specific capacitance of 21.86 F g(-1)

Effects of SiC and SiC-GNP additions on the mechanical properties and oxidation behavior of NbB2

Monolithic NbB2, NbB2-SiC, and NbB2-SiC-GNP samples were produced by spark plasma sintering (SPS), and the effects of additives on the mechanical and thermal properties, microstructures, and oxidation behavior of the samples were investigated. The addition of SiC up to 30 vol% decreased the Vickers hardness of the binary composites due to microcrack formation. The fracture toughness and oxidation resistance of NbB2 were improved with the incorporation of SiC. Fracture toughness was higher for all the composites in comparison to monolithic NbB2, moreover the highest value of ~5.2 MPa·m1/2 exhibited by 3 vol% GNP-containing composite. A strong interface and homogeneous distribution of GNPs enhanced the thermal transfer properties and improved the oxidation resistance of selected NbB2-SiC ceramics in oxidation studies at 1200°C. A combination of high mechanical properties, high thermal conductivity, and low mass gain was achieved for the NbB2-SiC-GNP samples with 1 and 3 vol% GNPs

A narrow range multielectrochromism from 2,5-di-(2-thienyl)-1H-pyrrole polymer bearing pendant perylenediimide moiety

WOS: 000346543200016A new 2,5-di-(2-thienyl)-1H-pyrrole (SNS) moiety containing perylenediimide (PDI) acceptor as pendant side chain has been synthesized for an electroactive monomer and then directly deposited onto ITO/glass surface via electrochemical polymerization process. The observed electronic interaction only at the excited state due to the presence of phenylene spacer between SNS-donor and PDI-acceptor moiety leads to efficient fluorescence quenching. This charge separation behavior was also proved by theoretical DFT calculations. Thin films of the polymer electropolymerized onto transparent electrode exhibited ambipolar multi-electrochromic behavior including purple, violet-red-khaki-blue colors in both anodic and cathodic regime only between -1.2 and 1.0 V. We further demonstrated that this polymer film has a high contrast ratio (Delta T = 45% at 900 nm), a faster response (0.5 s), high coloration efficiency (254 cm(2) C-1) and retained its performance by 92% even after 5000 cycles. (C) 2014 Elsevier Ltd. All rights reserved.Canakkale Onsekiz Mart University Grants CommissionCanakkale Onsekiz Mart University [2010/99]We gratefully acknowledge the supports from Canakkale Onsekiz Mart University Grants Commission (Project Number: 2010/99)

Enhanced capacitive behaviour of graphene based electrochemical double layer capacitors by etheric substitution on ionic liquids

WOS: 000540455700019In this study, we report the effect of etheric substituents in imidazolium and ammonium based ionic liquids (IL) on the performance of electrochemical double layer capacitors (EDLC) consisted of gel polymer electrolyte (GPE) and reduced graphene oxide (RGO) electrode. GPEs contain poly (vinylidene fluoride-hexafluompropylene) (PVDF-HFP) and the ILs. Ammonium and imidazolium based ionic liquids (ILs) differ by their length of etheric groups and etheric group contents, respectively. According to the cyclic voltammetry, galvanostatic chargedischarge and electrochemical impedance spectroscopy measurements, longer etheric group substituted {N-methyl-2- (2-methoxyethoxy)-N,N-bis [2- (2-methoxyethoxy)ethyl] ethan-1-aminium bis(tri-fluoromethanesulfonyl)imide (AMEt-TFSI) and ether substituted (3-allyl-1-[2-(2-methoxyethoxy)ethyl]-1H-imidazole-3-ium bis(trifluommethanesulfonyeimide (AL3IL-TFSI), tender specific capacitances of 250 Fg(-1) and 238 Fg(-1) and energy density values of 61.36 wh kg(-1) and 61.56 wh kg(-1), respectively.Ministry of Development of TurkeyTurkiye Cumhuriyeti Kalkinma Bakanligi [16 DPT002, 11DPT003]; Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [114M508]S.S. and C.V. would like to thank Prof. Dr. Pramod Singh Kumar and Prof. Dr. Yogesh Kumar for their theorical contribution during the evaluation of EDLC results. S.O and C.V. are thankful to Dr. H. Q. Nimal Gunaratne for the productive discussions and contributions related with the synthesis and characterization of the ILs. We would also like to acknowledge the Ministry of Development of Turkey for the project supports for some of the consumables (project #: 16 DPT002) and infrastructure (project #: 11DPT003). H.D. and C.V. thank to the project support of Scientific and Technological Research Council of Turkey (TUBITAK) (Project #: 114M508) for the synthesis and characterizations of graphene derivatives and for the fellowship support for HD. We would also like to thank the Izmir Institute of Technology, the Centre for Materials Research for BET analysis

Fabrication of room ambient perovskite solar cell using nickel oxide HTM

3rd International Conference on Science and Engineering of Materials (ICSEM) -- JUL 19-21, 2019 -- Sharda Univ, Noida, INDIAWOS:000621174700032Methyl ammonium lead iodide (MAPbI(3)) perovskite materials, have a significant impact in the field of solar cells. The solar-to power conversion efficiency of PSC, achieved so far is quite high as compared to the organic solar cells and dye sensitized solar cells. in this study we report the synthesis of perovskite (MAPbI(3)), the hole transport material (HTM) Nickel oxide and their application in the fabrication of perovskite solar cell (PSC) at room temperature. NiO has been an effective HTM due to its wideband gap and better carrier mobility. Noticeably, the PSC exhibits a power conversion efficiency (PCE) of 14.04%, which is the best performance reported so far in the sandwich structure employing NiO as HTM, with Voc = 0.78 V, J(sc) = 40 mA/cm(2) and fill factor = 0.45. (C) 2019 Elsevier Ltd. All rights reserved