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HighlightsThe slot-die-coated porous PbI2:CsI film assisted with nitrogen blowing can promote the rapid and complete transformation of perovskite film.The crystallinity and morphology of slot-die-coated perovskite film are significantly improved by controlling substrate temperature.Fully slot-die-coated perovskite solar cells achieve a power conversion efficiency (PCE) of 18.13%, and fully roll-to-roll printed flexible PSCs achieve a PCE of 13.00% in ambient condition.Perovskite solar cells (PSCs) have attracted tremendous attention as a promising alternative candidate for clean energy generation. Many attempts have been made with various deposition techniques to scale-up manufacturing. Slot-die coating is a robust and facile deposition technique that can be applied in large-area roll-to-roll (R2R) fabrication of thin film solar cells with the advantages of high material utilization, low cost and high throughput. Herein, we demonstrate the encouraging result of PSCs prepared by slot-die coating under ambient environment using a two-step sequential process whereby PbI2:CsI is slot-die coated first followed by a subsequent slot-die coating of organic cations containing solution. A porous PbI2:CsI film can promote the rapid and complete transformation into perovskite film. The crystallinity and morphology of perovskite films are significantly improved by optimizing nitrogen blowing and controlling substrate temperature. A power conversion efficiency (PCE) of 18.13% is achieved, which is promising for PSCs fabricated by two-step fully slot-die-coated devices. Furthermore, PSCs with a 1 cm2 area yield a champion PCE of 15.10%. Moreover, a PCE of 13.00% is obtained on a flexible substrate by the roll-to-roll (R2R) coating, which is one of the highest reported cells with all layers except for metal electrode fabricated by R2R process under ambient condition.

Organolead halide perovskite materials possess a combination of remarkable optoelectronic properties, such as steep optical absorption edge and high absorption coefficients, long charge carrier diffusion lengths and lifetimes. Taken together with the ability for low temperature preparation, also from solution, perovskite‐based devices, especially photovoltaic (PV) cells have been studied intensively, with remarkable progress in performance, over the past few years. The combination of high efficiency, low cost and additional (non‐PV) applications provides great potential for commercialization. Performance and applications of perovskite solar cells often correlate with their device structures. Many innovative device structures were developed, aiming at large‐scale fabrication, reducing fabrication cost, enhancing the power conversion efficiency and thus broadening potential future applications. This review summarizes typical structures of perovskite solar cells and comments on novel device structures. The applications of perovskite solar cells are discussed. Perovskite solar cells have been advancing rapidly as a new photovoltaic technology. Device structures have been evolving, demonstrating outstanding performance due to the extraordinary optical and electronic features of organolead halide perovskite materials. Typical structures and promising applications of perovskite solar cells are summarized and discussed. This technology appears to be well positioned for commercialization.

Highlights4-Terminal inorganic perovskite/organic tandem solar cells were made by using semi-transparent inorganic perovskite solar cells and narrow-bandgap organic solar cells as the sub-cells, yielding a power conversion efficiency of 22.34%, which is the highest efficiency for inorganic perovskite/organic tandem solar cells.Inorganic perovskite solar cells made by drop-coating (self-spreading) gave much higher power conversion efficiency than the cells made by spin-coating, enabling perovskite/organic tandem solar cells with higher efficiency.After fast developing of single-junction perovskite solar cells and organic solar cells in the past 10 years, it is becoming harder and harder to improve their power conversion efficiencies. Tandem solar cells are receiving more and more attention because they have much higher theoretical efficiency than single-junction solar cells. Good device performance has been achieved for perovskite/silicon and perovskite/perovskite tandem solar cells, including 2-terminal and 4-terminal structures. However, very few studies have been done about 4-terminal inorganic perovskite/organic tandem solar cells. In this work, semi-transparent inorganic perovskite solar cells and organic solar cells are used to fabricate 4-terminal inorganic perovskite/organic tandem solar cells, achieving a power conversion efficiency of 21.25% for the tandem cells with spin-coated perovskite layer. By using drop-coating instead of spin-coating to make the inorganic perovskite films, 4-terminal tandem cells with an efficiency of 22.34% are made. The efficiency is higher than the reported 2-terminal and 4-terminal inorganic perovskite/organic tandem solar cells. In addition, equivalent 2-terminal tandem solar cells were fabricated by connecting the sub-cells in series. The stability of organic solar cells under continuous illumination is improved by using semi-transparent perovskite solar cells as filter.

Introducing layered quasi-2D perovskite phases into a conventional 3D perovskite light-absorbing matrix is a promising strategy for overcoming the limited environmental stability of 3D perovskite solar cells. Here, we present a simple drop-casting method for preparing hybrid perovskite films comprising both quasi-2D and quasi-3D phases, formed using phenylethylammonium or iso-butylammonium as spacer cations. The film morphology, phase purity, and crystal orientation of the hybrid quasi-2D/3D perovskite films are improved significantly by applying a simple N2 blow-drying step, together with inclusion of methylammonium chloride as an additive. An enhanced power conversion efficiency of 16.0% is achieved using an iso-butylammonium-based quasi-2D/3D perovskite layer which, to our knowledge, is the highest recorded to date for a quasi-2D/3D perovskite solar cells containing a non-spin-cast perovskite layer prepared under ambient laboratory conditions.Perovskite solar cells have substantial potential for solar conversion, but developing simple and scalable fabrication processes is challenging. Here, a drop-casting process compatible with roll-to-roll production of quasi-2D/3D perovskite layers is developed, with a conversion efficiency of up to 16%.

How to deliver chemotherapeutic drugs efficiently and selectively to tumor cells to improve therapeutic efficacy remains a difficult problem. We herein construct an efficient cell-targeting drug delivery system (Sgc8-MSN/Dox) based on aptamer-modified mesoporous silica nanoparticles that relies on the tumor-targeting ability of the aptamer Sgc8 to deliver doxorubicin (Dox) to leukemia cells in a targeted way, thereby improving therapeutic efficacy and reducing toxicity. In this work, Sgc8-MSN/Dox showed sustained Dox release, and they targeted and efficiently killed CCRF-CEM human acute T lymphocyte leukemia cells, suggesting potential as a cancer therapy.

Background Whether body mass index (BMI) is a significant risk factor for recurrence of primary spontaneous pneumothorax (PSP) remains controversial. The purpose of this study was to examine whether BMI and other factors are linked to risk of PSP recurrence. Methods A consecutive cohort of 273 patients was retrospectively evaluated. Patients were divided into those who experienced recurrence ( n  = 81) and those who did not ( n  = 192), as well as into those who had low BMI ( n  = 75) and those who had normal or elevated BMI ( n  = 198). The two pairs of groups were compared in terms of baseline data, and Cox proportional hazards modeling was used to identify predictors of PSP recurrence. Results Rates of recurrence among all 273 patients were 20.9% at 1 year, 23.8% at 2 years, and 28.7% at 5 years. Univariate analysis identified the following significant predictors of PSP recurrence: height, weight, BMI, size of pneumothorax, and treatment modality. Multivariate analyses identified several risk factors for PSP recurrence: low BMI, pneumothorax size ≥50%, and non-surgical treatment. Kaplan–Meier survival analysis indicated that patients with low BMI showed significantly lower recurrence-free survival than patients with normal or elevated BMI ( P  < 0.001). Conclusions Low BMI, pneumothorax size ≥50%, and non-surgical treatment were risk factors for PSP recurrence in our cohort. Low BMI may be a clinically useful predictor of PSP recurrence.

The intrinsic phase instability of CsPbI2Br perovskite hinders its development and application in solar cells. Herein, we adopt 1‐butyl‐3‐methylimidazolium hexafluorophosphate (BMIMPF6), a hydrophobic ionic liquid (IL), to improve the phase stability of CsPbI2Br. Density functional theory calculation reveals that the formation energy of CsPbI2Br with BMIMPF6 is reduced, thereby restraining the [PbX6]4− octahedral tilting. The reduced structural distortion and relaxed lattice strain result in improved phase stability of CsPbI2Br. In addition, the interfacial dipole moment increases after introducing BMIMPF6, which facilitates the charge transfer. Consequently, the CsPbI2Br solar cells with BMIMPF6 deliver a power conversion efficiency (PCE) of 16.2% along with excellent stability. The unencapsulated devices with BMIMPF6 maintain 98.9%, 88.6%, and 99.5% of the initial PCEs after 1200 h storage in N2, 1000 h storage in air (30% relative humidity), and 200 thermal cycles (25–100°C), respectively. An ionic liquid (BMIMPF6) was introduced into CsPbI2Br films, resulting in relaxed strain, suppressed [PbX6]4− octahedral tilting, and improved phase stability. The CsPbI2Br films with BMIMPF6 showed no phase change after 7 months in air. CsPbI2Br solar cells kept 88.6% and 99.5% of the initial PCEs after 1000 h storage in air and 200 thermal cycles (25–100°C), respectively.

HighlightsSynergistic effect triggers the Ostwald ripening for the downward recrystallization of perovskite to form buried submicrocavities as light output coupler.The simulation suggests the buried submicrocavities can improve the light out-coupling efficiency from 26.8% to 36.2% for near-infrared light.Light-emitting diodes yields peak external quantum efficiency increasing from 17.3% at current density of 114 mA cm−2 to 25.5% at current density of 109 mA cm−2 and a radiance increasing from 109 to 487 W sr−1 m−2 with low rolling-off.Embedding submicrocavities is an effective approach to improve the light out-coupling efficiency (LOCE) for planar perovskite light-emitting diodes (PeLEDs). In this work, we employ phenethylammonium iodide (PEAI) to trigger the Ostwald ripening for the downward recrystallization of perovskite, resulting in spontaneous formation of buried submicrocavities as light output coupler. The simulation suggests the buried submicrocavities can improve the LOCE from 26.8 to 36.2% for near-infrared light. Therefore, PeLED yields peak external quantum efficiency (EQE) increasing from 17.3% at current density of 114 mA cm−2 to 25.5% at current density of 109 mA cm−2 and a radiance increasing from 109 to 487 W sr−1 m−2 with low rolling-off. The turn-on voltage decreased from 1.25 to 1.15 V at 0.1 W sr−1 m−2. Besides, downward recrystallization process slightly reduces the trap density from 8.90 × 1015 to 7.27 × 1015 cm−3. This work provides a self-assembly method to integrate buried output coupler for boosting the performance of PeLEDs.

HighlightsThe CuaAgm1Bim2In/CuI bilayer films are prepared simultaneously in situ by a one-step low-temperature gas-solid phase diffusion induced elemental reaction without spin coating.A new type of CuaAgm1Bim2In photovoltaic material was originally designed to reduce the bandgap of this class of materials from 2.06 to 1.78 eV by breaking the restriction of double perovskite structure with a ratio of Ag:Bi = 1:1.The power conversion efficiency (PCE) of solar cell with a structure of FTO/TiO2/CuaAgm1Bim2In/CuI/carbon reached 2.76%, which is the highest PCE for CuaAgm1Bim2In absorbers.Lead-free inorganic copper-silver-bismuth-halide materials have attracted more and more attention due to their environmental friendliness, high element abundance, and low cost. Here, we developed a strategy of one-step gas–solid-phase diffusion-induced reaction to fabricate a series of bandgap-tunable CuaAgm1Bim2In/CuI bilayer films due to the atomic diffusion effect for the first time. By designing and regulating the sputtered Cu/Ag/Bi metal film thickness, the bandgap of CuaAgm1Bim2In could be reduced from 2.06 to 1.78 eV. Solar cells with the structure of FTO/TiO2/CuaAgm1Bim2In/CuI/carbon were constructed, yielding a champion power conversion efficiency of 2.76%, which is the highest reported for this class of materials owing to the bandgap reduction and the peculiar bilayer structure. The current work provides a practical path for developing the next generation of efficient, stable, and environmentally friendly photovoltaic materials.

A 54π-electron fullerene acceptor, indene bis-methano [60] fullerene （IBMF）, having one indene and two sterically compact CH2 groups was developed. Using P3HT as donor, IBMF solar cells gave a PCE of 5.18%, which is higher than that for solar cells based on IC60TA, which has three indenes. The superior performance of IBMF solar cells originates from higher mobility of IBMF and better morphology for IBMF/P3HT blend films.