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Stock index price forecasting is a consistent focus of business intelligence. Various factors influence stock index price forecasting, such as technical indicators, financial news, business status, and the macroeconomics situation. In addition, many studies have shown that the exchange rate is related to the stock index price; however, no study has examined whether the exchange rate can be used to forecast stock index prices. Therefore, this paper focuses on this topic and uses exchange rate to predict China stock index price for the first time. Firstly, we compare the association of China stock index price with different data sources to illustrate the feasibility of using the exchange rate to predict stock index prices. Then, we generate some additional technical features of the exchange rate and propose a strategy to predict the stock index price. Finally, we compare the forecast results of China's stock index price based on four data sources, i.e., technical indicators, exchange rate data, US market index data and finance news data from January 3, 2017 to March 20, 2019. Experimental results demonstrate that the performance of exchange rate data for stock index prediction is comparable to other popular data sources and that, in some prediction periods, the exchange rate outperforms such data sources. The results confirm that the exchange rate could be used for forecasting the Shanghai Composite Index prices.

Rapidly removing oil from emulsified produced water has become one of the most common problems that needs to be urgently resolved as gas-field exploitation enters its later stages, and an effective technique has not yet been established thus far. This paper introduces experimental research and further industrial application of a novel combined fibrous coalescer in the treatment of produced water in an offshore gas-field. Metal and oleophilic polymer fibers were combined at a certain proportion and woven into a fibrous bed with specific structural and geometric properties, which was used as the core separation component of the coalescer. The industrial operation results showed that the oil pollutant concentration of the produced water treated with the novel coalescer was reduced from 1200 to 25 mg/L, well below the 45 mg/L national discharge standard, under a residence time of 180 s and pressure drop of 30 psi. This is the first successful and significant industrial application of the technique in an offshore gas-field, providing a promising alternative for resolving the difficulty of produced water treatment in similar gas-fields, promoting further applications of the technique, and contributing to cleaner production and marine conservation.

Several studies are described that contribute to the systematic exploration of new aspects of digestion, fermentation, and biological activities of pectic polysaccharides (PPS) leading to a better understanding of prebiotics. Inflammatory bowel disease (IBD) is thought to be associated with the dysbacteriosis induced by different environmental agents in genetically susceptible persons. PPS are considered as an indispensable gut-microbiota-accessible carbohydrate that play a dominant role in maintaining gut microbiota balance and show a better effect in ameliorating IBD than some traditional prebiotics. The aim of this review is to summarize the fermentation characteristics of PPS, highlight its role in improving IBD, and propose a view that PPS may be a new and effective prebiotic.

In this study, brewery wastewater was used as the treatment in exploring the optimal conditions and maximum processing efficiency of the completely mixed anaerobic biofilm reactor (CMABR) under the conditions of hydraulic retention time (HRT) (18 h, 24 h, and 30 h) with a rotational speed (70 rpm, 100 rpm, and 130 rpm) and influent total alkalinity (TA) (20 mmol/L, 25 mmol/L, and 30 mmol/L), which was measured by the response surface methodology (RSM). The results indicated that the maximum chemical oxygen demand (COD) removal ratio was achieved under the following conditions: HRT of 21.42 h, rotational speed of 101.34 rpm, and influent TA of 25.22 mmol/L. Analysis by scanning electron microscope (SEM) showed that the microorganisms were successfully immobilized on the polyurethane fillers before the reactor began operation. High-throughput sequencing indicated that Methanothrix and Methanospirillum were the dominant contributors for COD removal in the CAMBR under these optimum conditions.

Fine coal gangue aggregate (CGA) has a high water absorption, which increases the cracking risk of mortar caused by dry shrinkage. The effects of polypropylene (PP) fiber on the fluidity, strength, dry shrinkage, and cracking of CGA mortar were studied in this paper. The results show that PP fiber reduces the fluidity of CGA mortar, but PP fiber improves compressive and flexural strengths, especially at the early stages. PP fiber also effectively decreases dry shrinkage and the risk of cracking. Overall, PP fiber can effectively improve the properties of CGA mortar.

At present, there are two main standards, ISO 23828 : 2013 and SAE J 2572–2014, which prescribe the hydrogen consumption test using the pressure method, gravimetric method, and flow method. However, these methods do not meet the test requirements for electric energy consumption and the range of plug-in hybrid fuel cell vehicles (FCVs) which are the main technical considerations in China and Europe. In this paper, a new test method for the hydrogen consumption, electric energy consumption, and range of FCVs is proposed without the use of additional hydrogen supply, measurement instruments, or energy consumption correction, which can improve the operability of the test and avoid the conversion between electric energy and hydrogen. One plug-in hybrid FCV and one nonplug-in hybrid FCV were tested using the proposed method. The results show that the new method meets the requirements of fuel economy test for FCVs with hydrogen consumption rate, electric energy consumption rate, the range for plug-in hybrid FCVs, hydrogen consumption rate, and the range for nonplug-in FCVs.

In this paper, a unique operation mechanism of loop heat pipe (LHP) was proposed. To test the performance of LHP under this new mechanism, a visual flat LHP evaporator prototype and an open experimental system were designed and assembled, and start-up experiment and variable heat load experiment were done respectively to obtain the actual operation characteristics, such as the evaporator thermal resistance (Re), total thermal resistance (Rt), start-up time and temperature of base plate. The proposed LHP had better overall performance during the start-up tests when He value of EC was set to 0.5mm, and its corresponding Re and Rt value were 0.035 K/W and 0.451 K/W when the heating power was 208w. Meanwhile, as per the heat load applied to the base plate, the whole variable heat load experiment could be divided into three distinct stages: low heat load stage, efficiency operation stage and dry-out stage. Moreover, the results also showed that the circulation driven head formed inside of the EC played an important role in promoting the operation performance, especially when the wick, the vapour-liquid interface and the bottom of the evaporator arrived at a reasonable situation.

Decreasing particle size is an efficient strategy for improving the lithium storage properties of Li3V2(PO4)3 (LVP) due to a shorter transport distances of lithium ion and electrons. However, designing and synthesizing LVP nanocrystals (NCs) with sizes smaller than 30 nm remains a challenge. In this work, we developed a facile approach for the fabrication of the monodisperse LVP NCs through a robust high-temperature organic-phase method. The thermodynamics of the synthesis and the possible reaction mechanism were investigated. The results indicate that the organic-phase environment (at 320 °C) may not thermodynamically allow the crystallization of LVP. Nevertheless, oleic acid (OA) and oleylamine (OAm) are essential as capping agents to hinder the agglomeration and growth of the particles. Based on the thermodynamic need, calcination is essential to prepare LVP. The surface electronic conductivity of the LVP NCs was enhanced through a subsequent carbon-coating treatment. The optimum combination of reduction and carbon coating is very favorable for the kinetics of electron transfer and lithium ion diffusion. Therefore, the fabricated LVP@C NCs exhibit superior lithium storage properties with excellent rate capability (84 mA h g−1 at a rate of 20C) and perfect cyclic stability (96.2% capacity retention after 200 cycles at 5C), demonstrating their potential application in high-performance lithium-ion batteries.

The effect of different volume fractions of pre-existing martensite on the low-temperature bainitic transformation and microstructures was quantitatively analyzed by dilatometer, optical microscope and scanning electron microscope. The results showed that pre-existing martensitic transformation accelerated the subsequent low-temperature bainitic transformation, and the incubation period and completion time of bainitic reaction were significantly shortened. This phenomenon was attributed to the increasing nucleation sites caused by the introduced dislocations in austenite due to the formation of pre-existing martensite. However, it was noteworthy that, because of the increased bainitic plates adjacent to the pre-existing martensitic plates, the probability of the impingement of bainitic plates during growth was increased, which resulted in a decrease in the maximum attainable volume fraction of bainite.

Highly adherent wettability patterns on the substrate-independent superhydrophobic surfaces of trimethoxyoctadecylsilane modified titanium dioxide (TiO2)-based coatings were prepared by using commercial photolithography. Three custom unidirectional channels with gradient wettability patterns were obtained by spatially selective wettability conversion from superhydrophobic to superhydrophilic when the coatings were exposed to ultraviolet light (∼365 nm). The movement behavior of droplets on these unidirectional channels was studied and the displacement of droplet movement was effectively controlled. Integrating the idea of gradient wettability patterns into planar microfluidic devices (microreactors), a self-driven fluid transport was achieved to realize droplet metering, merging or reaction, and rapid transport. This self-driven fluid transport with gradient wettability patterns has great potential in fabricating a new category of pump-free microfluidic systems that can be used in various conditions.

A non-pneumatic tire appears to have advantages over the conventional pneumatic tire in terms of flat proof and maintenance free. A mechanical elastic wheel (MEW) with a non-pneumatic elastic outer ring which functions as the air of the pneumatic tire was presented. The structure of MEW is non-inflatable integrated configuration and the effect of hinges is accounted for only in tension. To establish finite element model of MEW, various nonlinear factors, such as the geometrical nonlinearity, material nonlinearity and contact nonlinearity, were considered. Load characteristic test was conducted by tyre dynamic test-bed to obtain force-deflection curves. And the validity of the finite element model was validated through load characteristic test. The vehicle vibration performance respectively based on the MEW and the radial tire was compatative studied under pulse input experiment conditions. The result showed that the vehicle concluding the new mechanical elastic wheel met the vibration performance requirements and vibration performance regularity of pneumatic tire. The results could be used as the thesis reference for the improvement of new mechanical elastic wheel.

The superhydrophobicity of biological surfaces with dual-scale roughness has recently received considerable attention because of the unique wettability of such surfaces. Based on this, artificial micro/nano hierarchical structures with structured sidewalls and smooth sidewalls were designed and the influences of sidewall configurations (i.e., structured and smooth) on the wetting state of micro/nano hierarchical structures were systematically investigated based on thermodynamics and the principle of minimum free energy. Wetting transition and superhydrophobic stability were then analyzed for a droplet on dual-scale rough surfaces with structured and smooth sidewalls. Theoretical analysis results show that dual-scale rough surfaces with structured sidewalls have a larger “stable superhydrophobic region” than those with smooth sidewalls. The dual-scale rough surfaces with smooth sidewalls can enlarge the apparent contact angle (ACA) without improvement in the superhydrophobic stability. By contrast, dual-scale rough surfaces with structured sidewalls present an advantage over those with smooth sidewalls in terms of enlarging ACA and enhancing superhydrophobic stability. The proposed thermodynamic model is valid when compared with previous experimental data and numerical analysis results, which is helpful for designing and understanding the wetting states and superhydrophobic stability of surfaces with dual-scale roughness.

With the rapid development of autonomous vehicles, the demand for reliable positioning results is urgent. Currently, the ground vehicles heavily depend on the Global Navigation Satellite System (GNSS) and the Inertial Navigation System (INS) providing reliable and continuous navigation solutions. In dense urban areas, especially narrow streets with tall buildings, the GNSS signals are possibly blocked by the surrounding tall buildings, and under this condition, the geometry distribution of the in-view satellites is very poor, and the None-Line-Of-Sight (NLOS) and Multipath (MP) heavily affects the positioning accuracy. Further, the INS positioning errors will quickly diverge over time without the GNSS correction. Aiming at improving the position accuracy under signal challenging environment, in this paper, we developed an MIMU(Micro Inertial Measurement Unit)/Odometer integration system with vehicle state constraints (MO-C) for improving the vehicle positioning accuracy without GNSS. MIMU/Odometer integration model and the constrained measurements are given in detail. Several field tests were carried out for evaluating and assessing the MO-C system. The experiments were divided into two parts, firstly, field testing with data post-processing and real-time processing was carried out for fully assessing the performance of the MO-C system. Secondly, the MO-C was implemented in the BeiDou Satellite Navigation System (BDS)/integrated navigation system (INS) for evaluating the MO-C performance during the BDS signal outage. The MIMU standalone positioning accuracy was compared with that from the MIMU/Odometer integration (MO), MO-C and MIMU with constraints (M-C) for assessing the Odometer, and the influence of the constraint on the positioning errors reduction. The results showed that the latitude and longitude errors could be suppressed with Odometer assisting, and the height errors were suppressed while the state constraints were included.

Self-crosslinking fluorinated polyacrylate latexes based on butyl acrylate (BA), fluorine monomer octafluoropentyl methacrylate (OFPMA), self-crosslinking functional monomers acrylic acid (AA) and 2-hydroxyethyl acrylate (HEA) were synthesized by a monomer-starved seeded semi-continuous emulsion polymerization process. The latexes and their corresponding films were characterized by laser particle size analyser, Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), contact angle goniometer, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Results indicated that the particle size of the latexes and the gel content of the films were both independent of the amount of OFPMA employed. On the other hand, the particle size of the latexes decreased and the gel content of the films increased with the incorporation of AA and HEA as expected. Glass transition temperature (Tg) and the thermal stability of the copolymer were both improved gradually as OFPMA content increased. XPS, AFM and water contact angle measurement indicated that the fluoroalkyl groups had a tendency to enrich on the surface of the films. However, this enrichment of fluorine on the film surface was reduced after the introduction of self-crosslinking functional monomers into the system. Finally, the adhesive property of the latexes was evaluated for application as a pressure sensitive adhesive (PSA).

For both polyimide membranes in aerospace and graphene membranes in nanoelectronics with surface accuracy requirements, wrinkles due to the extreme out-of-plane flexibility yield inverse influences on the properties and applications of membranes. In this study, on the basis of discrete topology optimization, we propose a prenecking strategy by adopting elliptical free edges to suppress the stretch-induced wrinkling. This prenecking strategy with the computer-aided-design (CAD)-ready format is versatile to eliminate wrinkles in stretched membranes with clamped ends and achieve wrinkle-free performances. The wrinkle-free capability of the prenecking strategy, capable of satisfying the shape accuracy requirements, indicates that by suffering insignificant area loss, concerning of wrinkling problems in membranes is no further required. As compared with the existing researches focusing on studying wrinkling behaviors, the prenecking strategy offers a promising solution to the stretch-induced wrinkling problem by eliminating wrinkles through design optimization.

The wetting transition on submersed superhydrophobic surfaces with hierarchical structures and the influence of trapped air on superhydrophobic stability are predicted based on the thermodynamics and mechanical analyses. The dewetting transition on the hierarchically structured surfaces is investigated, and two necessary thermodynamic conditions and a mechanical balance condition for dewetting transition are proposed. The corresponding thermodynamic phase diagram of reversible transition and the critical reversed pressure well explain the experimental results reported previously. Our theory provides a useful guideline for precise controlling of breaking down and recovering of superhydrophobicity by designing superhydrophobic surfaces with hierarchical structures under water.

Aiming at the accuracy of estimation of vehicle’s mass center sideslip angle, an estimation method of slip angle based on general regression neural network (GRNN) and driver-vehicle closed-loop system has been proposed: regarding vehicle’s sideslip angle as time series mapping of yaw speed and lateral acceleration; using homogeneous design project to optimize the training samples; building the mapping relationship among sideslip angle, yaw speed, and lateral acceleration; at the same time, using experimental method to measure vehicle’s sideslip angle to verify validity of this method. Estimation results of neural network and real vehicle experiment show the same changing tendency. The mean of error is within 10% of test result’s amplitude. Results show GRNN can estimate vehicle’s sideslip angle correctly. It can offer a reference to the application of vehicle’s stability control system on vehicle’s state estimation.

In this paper we propose a fully convolutional encoder-decoder framework for image residual transformation tasks. Instead of only using per-pixel loss function, the proposed framework learn end-to-end mapping combined with perceptual loss function that depend on low-level features from a pre-trained network. Pointing out the mapping function in order to handle noise-free image by introduce identity mapping. And through an analysis of the interplay between the neural networks and the underlying noisy distribution which they seeking to learn. We also show how to construct a uniform transform, which is then used to make a single deep neural network work well across different levels of noise. Comparing with previous approaches, ours achieves better performance. The experimental results indicate the efficiency of the proposed algorithm to cope with image denoising tasks.

Four-petal Gaussian beam is a special type of Gaussian beam, and its propagation properties are widely used in micro optics, optical communication and splitting technology. Recently, the generations and the properties of different types of hollow beams have become a hot research topic, such as research on hollow optical vortex beams. The Gyrator transform can be used to fulfill the mode conversion of laser beam. In this paper, based on the Gyrator transform, the analytical expression of four-petal Gaussian beam passing through such a transform system is derived, and the intensity distribution and the corresponding phase distribution associated with the transforming four-petal Gaussian beam are analyzed by numerical simulations. It is found that the four-petal Gaussian beam can be transformed into rectangular hollow beam by Gyrator transform, under the appropriate conditions of the beam order, the beam parameter, the transform angle of Gyrator transform, and the waist width. For the beam order n=m=3, the transform angle of Gyrator transform = 0.4133, the beam parameter K=30, and the waist width = 0.9, the rectangular hollow optical vortex beams can be obtained. Under such conditions, the maximum intensities appear in the four corners, and they are almost uniform on the four sides. The effects of the beam parameters, the transform angle, and the beam order on the distributions of intensity and phase of the rectangular hollow beam are analyzed in detail. The numerical results show that for the beam parameter K10, the rectangular hollow beam always is obtained, and for a lager beam parameter, the intensity distribution of the rectangular hollow beam is more uniform. Different beam order generates different type of hollow beam. For example, for n=m = 2, = 1.2, K = 30, and = 0.5409, a new strange circular hollow beam with solid circular nucleus can be obtained. The transform angle of Gyrator transform has a significant effect on the energy distribution of the hollow beam. When the transform angle changes in a small range, the uniformity of the intensity distribution of the rectangular hollow beam is lost. The bigger the transform angle change, the more serious the loss of uniformity of the hollow beam intensity is. The size of the hollow beam bright ring is determined by the waist width of the four-petal Gaussian beam: the larger the waist width, the smaller the bright ring is. The results further enriches the applications of Gyrator transform system and the four-petal Gaussian beam in the beam shaping.

A novel composite drug carrier with excellent sustained and pH-sensitive release performance was prepared by mixing hollow hydroxyapatite (HA) microspheres and chitosan solution with pH-sensitive characteristics. The hollow HA microspheres with mesopores filled on their multilayered spherical shell were obtained by converting borate glass with a novel composition of 19Na2O-17CaO-64B2O3 (wt%). The structure, phase composition and morphology of HA microspheres were characterized by SEM, SEM-EDS, XRD, FTIR and N2 adsorption-desorption measurements. The results indicated that the HA microspheres were B-type carbonated HA with hollow structure, in which the carbonate ions occupied the phosphate sites. The drug release results indicated that the HA microspheres generated burst release at initial stage. Coating the hollow HA microspheres with chitosan (CS) reduced the vancomycin release amount and release rate significantly. Meanwhile, the release profile of vancomycin into PBS with different pH value indicated that the CS-coated composite drug carrier shows pH-sensitive release property. The cumulative percentage of vancomycin released into PBS from the CS (20 g/L)-coated composite drug carrier was 85.63%, 65.85% and 71.85% for pH 6.0, 7.4, 8.5, respectively.

In this work, we develop a novel method of creating dark hollow beam with vortex by converting a sine-Gaussian beam (SeGB) with edge-dislocation and astigmatism through using fractional Fourier transform (FrFT) optical system. On the basis of the definition of the FrFT, an analytical transformation formula is derived for an astigmatic SeGB passing through such a transform system. By use of the derived formulae, the changes of the intensity distribution and the corresponding phase properties associated with the transforming astigmatic SeGBs are analytically discussed in detail. It is found that for an input SeGB without astigmatism, there is still a dark line or an edge dislocation associated with the intensity distribution of the FrFT beam along the initial dislocation line, similar to that of the input SeGB. However, when the input SeGB astigmatically passes through an FrFT optical system, the dark line of the intensity distribution of the input SeGB can be converted into a solitary zero point, or in other words, a dark hollow beam with a single-charge vortex can be produced by SeGB with an edge dislocation. The results reveal that the astigmatism plays a critical role in transforming a SeGB into a dark hollow one through the FrFT optical system. Furthermore, some numerical calculation results based on the derived formula are presented and discussed graphically. It is shown that for appropriate beam parameters and carefully adjusting the transform angle of FrFT, dark hollow beams with single-charge vortex and elongated elliptic geometry can be realized with astigmatic SeGBs. The influences of the beam parameters and the transform angle of FrFT optical system on the generation of perfect dark hollow beams are also investigated. The results demonstrate that the linear eccentricity of the dark hollow beam, which is roughly defined as the ratio of semi-minor axis to semi-major one of the intensity pattern, mainly depends on the Fresnel number. And the optimal linear eccentricity may be relatively large under carefully selecting the beam and optical system parameters. Moreover, optimal parameter values corresponding to perfect dark hollow beam configurations which can be experimentally accessed are presented. As is well known, there are two types of pure phase defects or dislocations in the optical fields:one is screw dislocation or vortex and the other is edge-dislocation. Due to their important applications, the propagation dynamics of optical vortices or edge dislocations are extensively studied both theoretically and experimentally. The vortex-edge dislocation interaction is investigated in detail. However, there are fewer reports on the direct conversion between a single edge dislocation and a vortex. Therefore, the results obtained in this paper represent a significant step forward in understanding the transformation dynamics between beams with pure edge dislocation and vortex, and also opens possibilities for their potential applications, e.g., in generating dark hollow beams with elliptic geometry using FrFT systems.

Improving the long-term stability of perovskite solar cells is critical to the deployment of this technology. Despite the great emphasis laid on stability-related investigations, publications lack consistency in experimental procedures and parameters reported. It is therefore challenging to reproduce and compare results and thereby develop a deep understanding of degradation mechanisms. Here, we report a consensus between researchers in the field on procedures for testing perovskite solar cell stability, which are based on the International Summit on Organic Photovoltaic Stability (ISOS) protocols. We propose additional procedures to account for properties specific to PSCs such as ion redistribution under electric fields, reversible degradation and to distinguish ambient-induced degradation from other stress factors. These protocols are not intended as a replacement of the existing qualification standards, but rather they aim to unify the stability assessment and to understand failure modes. Finally, we identify key procedural information which we suggest reporting in publications to improve reproducibility and enable large data set analysis., This article is based upon work from COST Action StableNextSol MP1307 supported by COST (European Cooperation in Science and Technology). M.V.K., E.A.K., V.B. and A.O. thank the financial support of the United States – Israel Binational Science Foundation (grant no. 2015757). E.A.K., A.A. and I.V.-F. acknowledge partial support from the SNaPSHoTs project in the framework of the German-Israeli bilateral R&D cooperation in the field of applied nanotechnology. M.S.L. thanks the financial support of National Science Foundation (ECCS, award #1610833). S.C., M.Manceau and M.Matheron thank the financial support of European Union’s Horizon 2020 research and innovation programme under grant agreement no 763989 (APOLO project). F.D.R. and T.M.W. would like to acknowledge the support from the Engineering and Physical Sciences Research Council (EPSRC) through the SPECIFIC Innovation and Knowledge Centre (EP/N020863/1) and express their gratitude to the Welsh Government for their support of the Ser Solar programme. P.A.T. acknowledges financial support from the Russian Science Foundation (project No. 19-73-30020). J.K. acknowledges the support by the Solar Photovoltaic Academic Research Consortium II (SPARC II) project, gratefully funded by WEFO. M.K.N. acknowledges financial support from Innosuisse project 25590.1 PFNM-NM, Solaronix, Aubonne, Switzerland. C.-Q.M. would like to acknowledge The Bureau of International Cooperation of Chinese Academy of Sciences for the support of ISOS11 and the Ministry of Science and Technology of China for the financial support (no. 2016YFA0200700). N.G.P. acknowledges financial support from the National Research Foundation of Korea (NRF) grants funded by the Ministry of Science, ICT Future Planning (MSIP) of Korea under contracts NRF-2012M3A6A7054861 and NRF-2014M3A6A7060583 (Global Frontier R&D Program on Center for Multiscale Energy System). CSIRO’s contribution to this work was conducted with funding support from the Australian Renewable Energy Agency (ARENA) through its Advancing Renewables Program. A.F.N gratefully acknowledges support from FAPESP (Grant 2017/11986-5) and Shell and the strategic importance of the support given by ANP (Brazil’s National Oil, Natural Gas and Biofuels Agency) through the R&D levy regulation. Y.-L.L. and Q.B. acknowledge support from the National Science Foundation Division of Civil, Mechanical and Manufacturing Innovation under award no. 1824674. S.D.S. acknowledges the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (HYPERION, grant agreement no. 756962), and the Royal Society and Tata Group (UF150033). The work at the National Renewable Energy Laboratory was supported by the US Department of Energy (DOE) under contract DE-AC36-08GO28308 with Alliance for Sustainable Energy LLC, the manager and operator of the National Renewable Energy Laboratory. The authors (J.J.B, J.M.L., M.O.R, K.Z.) acknowledge support from the ‘De-risking halide perovskite solar cells’ program of the National Center for Photovoltaics, funded by the US Department of Energy, Office of Energy Efficiency and Renewable Energy, Solar Energy Technology Office. The views expressed in the article do not necessarily represent the views of the DOE or the US Government. H.J.S. acknowledges the support of EPSRC UK, Engineering and Physical Sciences Research Council. V.T. and M.Madsen acknowledge ‘Villum Foundation’ for funding of the project CompliantPV, under project no. 13365. M.Madsen acknowledges Danmarks Frie Forskningsfond, DFF FTP for funding of the project React-PV, no. 8022-00389B. M.G. and S.M.Z. thank the King Abdulaziz City for Science and technology (KACST) for financial support. S.V. acknowledges TKI-UE/Ministry of Economic Affairs for financial support of the TKI-UE toeslag project POP-ART (no. 1621103). RC thanks the grants for Development of New Faculty Staff, Ratchadaphiseksomphot Endowment Fund. A.D.C. gratefully acknowledges funding from the European Union’s Horizon 2020 Research and Innovation Program (grant agreement no. 785219-GrapheneCore2 and no. 764047-ESPResSo). M.L.C. and H.X. acknowledges the support from Spanish MINECO for the grant GraPErOs (ENE2016-79282-C5-2-R), the OrgEnergy Excellence Network CTQ2016-81911- REDT, the Agència de Gestiód’Ajuts Universitaris i de Recerca (AGAUR) for the support to the consolidated Catalonia research group 2017 SGR 329 and the Xarxa de Referència en Materials Avançats per a l’Energia (Xarmae). ICN2 is supported by the Severo Ochoa program from Spanish MINECO (Grant no. SEV-2017-0706) and is funded by the CERCA Programme/Generalitat de Catalunya.