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The p-i-n structure for perovskite solar cells has recently shown significant advantages in minimal hysteresis effects, and scalable manufacturing potential using low-temperature solution processing. However, the power conversion efficiency (PCE) of the perovskite p-i-n structure remains low mainly due to limitations using a flat electron transport layer (ETL). In this work, we demonstrate a new approach using spray coating to fabricate the [6,6]-phenyl-C(61)-butyric acid methyl ester (PCBM) ETL. By creating a rough surface, we effectively improve the light trapping properties inside the PCBM ETL. We reveal that the spray coated PCBM can form a cross-linked network, which may facilitate better charge transport and enhance extraction efficiency. By improving the contact between the perovskite film and the PCBM ETL, a reduction in the trap states is observed resulting in a PCE increase from 13% to >17%.

transformers [2] and load bearing applications. [3] In the last few decades, the study of nanomaterials has become a central focus in nanoscience and nanotechnology. [4] In fact, many studies have shown that with reduction in size, nanomaterials display novel electrical, mechanical, chemical and optical properties, which are largely believed to be the result of surface and quantum confinement effects. [4,5] Remarkably, this trend has found traction in the metallic glass field where metallic glasses nanostructures (MGNs) demonstrate an important role in many applications such as light harvesting, [6] photovoltaic, [7] biomedical, [8] magneto-optical, [9] organic synthesis, [10] lithium-ion batteries [11] and electrocatalysis. [12] Recently, MGNs are receiving increased attention due to their distinguished performance, such as high activity and long term stability in electrocatalytic reactions. [12,13] Although several review papers have already covered the topic of nanopatterning of bulk metallic glasses (BMGs), [14][15][16] the correlation between recent synthetic methods and electrocatalytic applications for MGNs has not been thoroughly addressed. Moreover, there is currently no review that unites MGNs synthesized from different approaches (top-down and bottom-up) with conventional electrochemical reactions. Therefore, in this review our mission is to: 1) present a focused perspective on the latest fabrication techniques of MGNs toward the pursuit of novel electrocatalysts and electrodes; 2) highlight recent advances in computational screening and predictions that could be applied toward new metallic glass electrocatalyst discovery; and 3) report distinct advancements in electrocatalytic applications related to MGNs by creating a comprehensive discussion for commonly employed kinetic parameters and their connection with the unique material structure. Finally, as the first progress report on the metallic glass based electrocatalysts, we will also highlight some of the challenges that need to be addressed toward future progress in this field.BMGs are those metallic glasses (MGs) that can be made in 'bulk' scale with good glass forming abilities, [17] representing a versatile platform for many applications. To date, a wide range of BMG-forming alloys have been developed, including Zr-, [18] Fe-, [19] Cu-, [20] Ni-, [21] Ti-, [22] Mg-, [23] Pd-, [24] Au-, [25] and Pt-based compositions. [26] Moreover, the increased disorder brought by the higher degree of multinary systems is believed to contribute to improving the glass formation. [27] The evolution to multicomponent alloys of the most recent MG studies has also made them natural candidates for catalysis. The amorphous multinary Recent advances in metallic glass nanostructures (MGNs) are reported, covering a wide array of synthesis strategies, computational discovery, and design solutions that provide insight into distinct electrocatalytic applications. A brief introduction to the development and unique features of MGNs with an overview of top-down and bottom-up sy...

The successful commercialization of perovskite solar cells (Pvs-SCs) calls for the need to find low-temperature processable interlayers with outstanding charge-transport features. In this work, we strategically blend poly(2-ethyl-2-oxazoline) (PEOz) with PEDOT:PSS as the modified hole transport layer (HTL) to achieve high-efficiency P-I-N CHNHPbI Pvs-SCs. The PEOz-PEDOT:PSS HTL exhibits enhanced features over the conventional layer including the following: (1) promoting perovskite with enlarged grain sizes to decrease the perovskite layer's recombination, (2) increasing the work function of the HTL, and (3) decreasing the noncapacitive current in Pvs-SCs. Remarkably, we demonstrate a 17.39% power conversion efficiency with very low hysteresis and high V values of 1.075 V for Pvs-SCs with PEOz-PEDOT:PSS.

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Mechanical fragility and insufficient light absorption are two major challenges for thin flexible crystalline Si-based solar cells. Flexible hybrid single-walled carbon nanotube (SWNT)/Si solar cells are demonstrated by applying scalable room-temperature processes for the fabrication of solar-cell components (e.g., preparation of SWNT thin films and SWNT/Si p-n junctions). The flexible SWNT/Si solar cells present an intrinsic efficiency ≈7.5% without any additional light-trapping structures. By using these solar cells as model systems, the charge transport mechanisms at the SWNT/Si interface are investigated using femtosecond transient absorption. Although primary photon absorption occurs in Si, transient absorption measurements show that SWNTs also generate and inject excited charge carriers to Si. Such effects can be tuned by controlling the thickness of the SWNTs. Findings from this study could open a new pathway for designing and improving the efficiency of photocarrier generation and absorption for high-performance ultrathin hybrid SWNT/Si solar cells.

In order to bypass the limitation of bulk metallic glasses fabrication, we synthesized thin film metallic glasses to study the corrosion characteristics of a wide atomic% composition range, Mg(35.9-63%)Ca(4.1-21%)Zn(17.9-58.3%), in simulated body fluid. We highlight a clear relationship between Zn content and corrosion current such that Zn-medium metallic glasses exhibit minimum corrosion. In addition, we found higher Zn content leads to a poor in vitro cell viability. These results showcase the benefit of evaluating a larger alloy compositional space to probe the limits of corrosion resistance and prescreen for biocompatible applications.

are driven by human life support systems, scientific exploration and Earth observation equipment, telecommunications, and electric propulsion systems. There is great interest in highly efficient perovskite-structured thin-film solar cells for space applications. [1,2] These are promising candidates due to their excellent optoelectronic characteristics, low-cost, high performance, [2][3][4] and their facile manufacturability [5] potentially suitable for in-space manufacturing. [6] These traits coupled with their defect tolerance, [7,8] and radiation tolerance [9] have garnered interest for aerospace applications. Prior to the widespread implementation of metal halide perovskites (MHPs) into the space environment, solar cells must pass rigorous American Institute of Aeronautics and Astronautics Standard 111 (AIAA-S111) space qualification testing. [10] Low earth orbit (LEO), 160-2000 km above the Earth's surface, is an ideal place to operate MHPs either on the International Space Station or on satellites. The harsh environment of LEO includes thermal cycling (±120 ⁰C), vacuum (10 −6 -10 −9 torr), ultra-violet radiation, exposure to atomic oxygen (flux 10 13 -10 15 AO/cm 2 with collision energy of 5 eV), plasma (10 6 cm −3 , ≤1 eV electron temperature), and ionizing radiation of electrons, protons, micrometeoroids (60 km s −1 ) and orbital debris (10 km s −1 ). [11] We must demonstrate MHP durability in relevant space environments to evidence feasibility. Implementing Metal halide perovskites (MHPs) have emerged as a prominent new photovoltaic material combining a very competitive power conversion efficiency that rivals crystalline silicon with the added benefits of tunable properties for multijunction devices fabricated from solution which can yield high specific power. Perovskites have also demonstrated some of the lowest temperature coefficients and highest defect tolerance, which make them excellent candidates for aerospace applications. However, MHPs must demonstrate durability in space which presents different challenges than terrestrial operating environments. To decisively test the viability of perovskites being used in space, a perovskite thin film is positioned in low earth orbit for 10 months on the International Space Station, which was the first long-duration study of an MHP in space. Postflight high-resolution ultrafast spectroscopic characterization and comparison with control samples reveal that the flight sample exhibits superior photo-stability, no irreversible radiation damage, and a suppressed structural phase transition temperature by nearly 65 K, broadening the photovoltaic operational range. Further, significant photo-annealing of surface defects is shown following prolonged light-soaking postflight. These results emphasize that methylammonium lead iodide can be packaged adequately for space missions, affirming that space stressors can be managed as theorized.