Organic–inorganic hybrid perovskite solar cells (PSCs) are promising third‐generation solar cells. They exhibit high power conversion efficiency (PCE) and, in theory, can be manufactured with less ...energy than several more established photovoltaic technologies, particularly solution‐processed PSCs. Various materials have been widely utilized to modify the buried bottom interface to improve the performance and long‐term stability of PSCs. Here, the latest progress in modifying the buried interface to enhance the performance and stability of PSCs is examined from a materials standpoint, which is classified into inorganic salts, the organic molecular and polymer, carbon materials, perovskite‐related materials, and 2D materials. This material perspective is useful in determining the tactics for achieving the theoretical PCE value of PSCs. It also serves as a solid reference of interface adjustment for other layered structure heterojunction devices.
This review surveys current developments in the buried interfacial of perovskite solar cells (PSCs) from a materials standpoint, including inorganic salts, organic molecules and polymers, carbon materials, perovskite materials, and 2D materials. It is expected to guide development to further boost the efficiency and stability as well as accelerate the application of PSCs. Moreover, the same applies to other optoelectronic devices.
Oxygen evolution reaction (OER) is a pivotal reaction in many technologies for renewable energy, such as water splitting, metal–air batteries, and regenerative fuel cells. However, this reaction is ...known to be kinetically sluggish and proceeds at rather high overpotential due to the universal scaling relationship, namely, the adsorption energies of intermediates are linearly correlated and cannot be optimized simultaneously. Several approaches have been proposed to break the scaling relationship by introducing additional active sites; however, positive experimental results are still absent. Herein, a different solution is suggested on the basis of dynamic tridimensional adsorption of the OER intermediates at NiO/NiFe layered double hydroxide intersection, by which the adsorption energy of each intermediate can be adjusted independently, so as to bypass the scaling relationship and achieve high catalytic performance. Experimentally, the OER overpotential is reduced to ≈205 mV at current density of 30 mA cm−2, which represents the best performance achieved by state‐of‐the‐art OER catalysts.
The oxygen evolution reaction (OER), a key reaction for energy conversion and storage, is kinetically sluggish due to the limits of the scaling relationship. A strategy to bypass the scaling relationship through dynamic tridimensional adsorption of OER intermediates is reported, and OER overpotential is reduced to 205 mV at current density of 30 mA cm−2.
2D titanium carbide (Ti3C2Tx MXene) is recognized as a promising material for pseudocapacitor electrodes in acidic solutions, while the current studies in neutral electrolytes show much poorer ...performances. By a simple hydrothermal method, vanadium‐doped Ti3C2Tx 2D nanosheets are prepared to tune the interaction between MXene and alkali metal adsorbates (Li+, Na+, and K+) in the neutral electrolyte. Maintaining the 2D morphology of MXene, the coexisting V3+ and V4+ are confirmed to form surface V–C and V–O species. At a medium doping level of V:Ti = 0.17:1, the V‐doped MXene exhibits the highest capacitance of 365.9 F g−1 in 2 m KCl (10 mV s−1) and excellent stability (5% loss after 5000 cycles), compared to only 115.7 F g−1 of pristine MXene. Density functional theory calculations reveal the stronger alkali metal ion–O interaction on V‐doped MXene surface than unmodified MXene and a further capacitance boost to 404.9 F g−1 using Li+‐containing neutral electrolyte is reported, which is comparable to the performance under acidic conditions.
Vanadium‐doped titanium carbide (Ti3C2Tx
MXene) nanosheets are prepared via a simple hydrothermal method to tune the interaction between MXene and alkali metal adsorbates (Li+, Na+, and K+) in neutral electrolytes. The strong alkali metal ion–O interaction on the V‐doped MXene surface boosts the capacitance to 404.9 F g−1, which is comparable to the performance under acidic conditions.
Worldwide habitat loss, land-use changes, and climate change threaten biodiversity, and we urgently need models that predict the combined impacts of these threats on organisms. Current models, ...however, overlook microhabitat diversity within landscapes and so do not accurately inform conservation efforts, particularly for ectotherms. Here, we built and field-parameterized a model to examine the effects of habitat loss and climate change on activity and microhabitat selection by a diurnal desert lizard. Our model predicted that lizards in rock-free areas would reduce summer activity levels (e.g. foraging, basking) and that future warming will gradually decrease summer activity in rocky areas, as even large rocks become thermally stressful. Warmer winters will enable more activity but will require bushes and small rocks as shade retreats. Hence, microhabitats that may seem unimportant today will become important under climate change. Modelling frameworks should consider the microhabitat requirements of organisms to improve conservation outcomes.
Few‐layer black phosphorus (BP) is an emerging 2D material suitable for energy applications. However, its controllable preparation remains challenging. Herein, a highly efficient route is presented ...for the scalable production of few‐layered BP nanosheets using a pulsed laser in low‐boiling point solvents. Changing the laser irradiation time, energy, and solvent type leads to precise control over the layer number and lateral size of the nanosheets with a narrow distribution. The process is understood by a plasma quenching mechanism and interlayer interaction weakened by the in situ generated vapor bubbles. The excellent control of the BP nanosheets enables morphological effects on Li‐ion battery performance to be studied. Low layer numbers benefit both charge transfer and Li+ ion diffusion, while a high aspect ratio can not only improve the charge transfer but also increase the Li+ ion diffusion path. This study delivers insights on the tailored fabrication of thin 2D materials using lasers for morphology‐dependent electrochemical energy conversion and storage.
Tuning black phosphorus (BP) thickness with a laser: A liquid‐phase exfoliation method assisted by a pulsed laser is described. The layer number and lateral size of few‐lsayered BP nanosheets depends on the laser duration and solvent. This few‐layered BP nanosheets enables the study of the relationship between morphology and BP‐based anode performance, showing thinner thickness and smaller lateral size promote faster Li+ transport.
It has been a hindering issue in perovskite solar cells that the interfaces between the perovskite and charge transport layers show significantly high concentrations of defects with an amount about ...100 times more than inside the bulk perovskite layer. The issue causes substantial reduction in both the efficiency and stability of the devices. Herein, a solid–solid contact approach is demonstrated to realize a multifunctional ion‐lock layer with strong chemical interaction to the perovskite layer. The multifunctional ion‐lock layer remarkably suppresses the interface defects and tunes the work function, contributing to promoting the carrier extraction, increasing the open‐circuit voltage, and enlarging the photocurrent. In addition, the multifunctional ion‐lock layer successfully locks ions from movement and thus improves the stability of the devices. Finally, with a multifunctional ion‐lock layer, the perovskite solar cells deliver an efficiency of up to 23.13% along with desirable long‐term operational, storage, and humidity stability. Consequently, the work offers guidelines for establishing defect‐suppressed interfaces between perovskites and hole transport layers.
A solid–solid contact strategy is proposed to form an ultra‐thin multifunctional ion‐lock interface layer in PSCs. This dense Nafion layer can lock the ions migration between perovskite and CTLs and eliminate the surface defects/traps of perovskite. The PSCs with Nafion multifunctional ion‐lock interface layer show a high efficiency of 23.13% with excellent humidity and operational stability.
Secure Multi-Party Computation (SMPC) is a generic cryptographic primitive that enables distributed parties to jointly compute an arbitrary functionality without revealing their own private inputs ...and outputs. Since Yao’s seminal work in 1982, 30 years of research on SMPC has been conducted, proceeding from pure theoretical research into real-world applications. Recently, the increasing prevalence of the newly emerging technologies such as cloud computing, mobile computing and the Internet of Thing has resulted in a re-birth of SMPC’s popularity. This has occurred mainly because, as a generic tool for computing on private data, SMPC has a natural advantage in solving security and privacy issues in these areas. Accordingly, many application-oriented SMPC protocols have been constructed. This paper presents a comprehensive survey on the theoretical and practical aspects of SMPC protocols. Specifically, we start by demonstrating the underlying concepts of SMPC, including its security requirements and basic construction techniques. Then, we present the research advances regarding construction techniques for generic SMPC protocols, and also the cutting-edge approaches to cloud-assisted SMPC protocols. Then, we summarize the concrete application-oriented protocols that are currently available, and finally, we present a discussion of the current literature and conclude this survey.
Exploiting high‐performance, robust, and cost‐effective electrocatalysts for the oxygen evolution reaction (OER) is crucial for electrochemical energy storage and conversion technologies. Engineering ...the interfacial structure of hybrid catalysts often induces synergistically enhanced electrocatalytic performance. Herein, a new strongly coupled heterogeneous catalyst with proper interfacial structures, i.e., CoO nanoclusters decorated on CoFe layered double hydroxides (LDHs) nanosheets, is prepared via a simple one‐step pulsed laser ablation in liquid method. Thorough spectroscopic characterizations reveal that strong chemical couplings at the hybrid interface trigger charge transfer from CoII in the oxide to FeIII in the LDHs through the interfacial FeOCo bond, leading to considerable amounts of high oxidation state CoIII sites present in the hybrid. Interestingly, the CoO/CoFe LDHs exhibit pronounced synergistic effects in electrocatalytic water oxidation, with substantially enhanced intrinsic catalytic activity and stability relative to both components. The hybrid catalyst achieves remarkably low OER overpotential and Tafel slope in alkaline medium, outperforming that of Ru/C and manifesting itself among the most active Co‐based OER catalysts.
A strongly coupled CoO/CoFe layered double hydroxides heterogeneous catalyst with proper interfacial structures is prepared via a one‐step laser ablation method. The strong chemical coupling at the hybrid interface triggers charge transfer through the interfacial FeOCo bond, resulting in abundant high oxidation state CoIII sites. The hybrid catalyst exhibits pronounced synergistic effects for the oxygen evolution reaction, with substantially enhanced intrinsic activity, turnover frequency, and stability.
The novel‐corona‐virus is presently accountable for 547,782 deaths worldwide. It was first observed in China in late 2019 and, the increase in number of its affected cases seriously disturbed almost ...every nation in terms of its economical, structural, educational growth. Furthermore, with the advancement of data‐analytics and machine learning towards enhanced diagnostic tools for the infection, the growth rate in the affected patients has reduced considerably, thereby making it critical for AI researchers and experts from medical radiology to put more efforts in this side. In this regard, we present a controlled study which provides analysis of various potential possibilities in terms of detection models/algorithms for COVID‐19 detection from radiology‐based images like chest x‐rays. We provide a rigorous comparison between the VGG16, VGG19, Residual Network, Dark‐Net as the foundational network with the Single Shot MultiBox Detector (SSD) for predictions. With some preprocessing techniques specific to the task like CLAHE, this study shows the potential of the methodology relative to the existing techniques. The highest of all precision and recall were achieved with DenseNet201 + SSD512 as 93.01 and 94.98 respectively.
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