Vacancy healing for stable perovskite solar cells via bifunctional potassium tartrate

Perovskite solar cell has gained widespread attention as a promising technology for renewable energy.However, their commercial viability has been hampered by their long-term stability and potential Pb leakage. Herein, we demonstrate a bifunctional passivator of the potassium tartrate(PT) to address both challenges. PT minimizes the Pb leakage in perovskites and also heals cationic vacancy defects, resulting in improved device performance and stability. Benefiting from PT modification, the power conversion efficiency(PCE) is improved to 23.26% and the Pb leakage in unencapsulated films is significantly reduced to 9.79 ppm. Furthermore, the corresponding device exhibits no significant decay in PCE after tracking at the maximum power point(MPP) for 2000 h under illumination(LED source, 100 mW cm^(-2)).

Improved interfacial adhesion for stable flexible inverted perovskite solar cells

Flexible perovskite solar cells have attracted widespread attention due to their unique advantages in lightweight,high flexibility,and easy deformation,which are suitable for portable electronics.However,the inverted(p-i-n)structured devices suffer from poor stability largely due to the low adhesion at the brittle interface(the hole transport layer/perovskite).Herein,zeolitic imidazolate framework-67(ZIF-67)is applied to inverted structured cells to optimize the interface and prolong the device lifetime.As a result,the flexible devices based on ZIF-67 obtain the champion power conversion efficiency of 20.16%.Over 1000 h under continuous light irradiation,the device retains 96%and 80%of its original efficiency without and with bias,respectively.Notably,devices show mechanical endurance with over 78%efficiency retention after 10,000 cycles of consecutive bending cycles(R=6 mm).The introduction of ZIF-67 suppresses the cracking in device bending,which results in improved environmental stability and bending durability.

MOFs in Emerging Solar Cells

Metal-organic framework(MOF)materials have attracted intense scientific interest in the solar cell research community owing to their unique physiochemical properties and various preparation methods.The photovoltaic performance and stability of resultant optoelectronic devices can also be improved by adopting MOF materials.This review pays close attention to the summary and generalization of recent representative achievements in solar cells by utilizing MOFs,including dye-sensitized solar cells,perovskite solar cells,organic solar cells,and so on.

Inhibitory Activity of Honeysuckle Extracts against Influenza A Virus In Vitro and In Vivo

Honeysuckle has been used in the treatment of influenza virus infection for thousands of years in China.However,its main active components and the functional mechanisms remain to be elucidated.Here,four honeysuckle extracts,including acids extract,flavonoids extract,total extract and acids-flavonoids mixture,were prepared to clarify the main active antiviral components.The cytopathic effect reduction assay showed that all the four extracts inhibited the replication of influenza viruses H1N1,H3N2 and the oseltamivir-resistant mutant strain H1N1-H275Y.The acids-flavonoids mixture had the strongest inhibitory effects in vitro with EC_(50) values of 3.8,4.1,and >20 lg/m L against H1N1,H3N2 and H1N1-H275Y,respectively,showing competitive antiviral activity with oseltamivir and ribavirin.Honeysuckle acids extract also showed the most significant antiviral activity in vivo.Oral administration of the acids extract at a dosage of 600 mg/kg/d effectively alleviated viral pneumonia,maintained body weight and improved the survival rate to 30% of the mice infected with a lethal dose of H1N1.The results of time-of-drug addition experiment and neuraminidase (NA) inhibition assay showed that honeysuckle extracts had a broad-spectrum inhibitory effect against influenza virus NAs.The flavonoid extract showed the strongest inhibitory effect on the NA of influenza virus H7N9 with an IC_(50) of 24.7 lg/m L.These results suggested that these extracts might exert their antiviral activity by suppressing the release of influenza viruses.Briefly,our findings demonstrate that acids and flavonoids extracts of honeysuckle are the major antiviral active components,and the acids extract has the potential to be developed into an antiviral agent against influenza virus,especially for oseltamivirresistant viruses.

Zinc Stannate Nanostructures for Energy Conversion

To date,ternary metal oxide semiconductor materials have attracted extensive attention worldwide due to their unique optoelectronic properties.As a classical ternary oxide,Zn2SnO4 is featured with the high electron mobility,wide band gap,negligible visible light absorption and tailorable electronic band structures.Thus,it is an ideal material for practical use in solar cells,lithium batteries,sensors,and photo-catalysts.In this review,we summarize the recent research progress of this material with the focus on the synthesis methods,nanostructures,and the resulting effects on the crystal structure,optical properties,and photoelectrochemical properties.Moreover,their potential applications in different devices are highlighted and carefully discussed.

Multi-agent coverage control for enhanced geohazard monitoring: a brief review

In recent years,cooperative coverage control of multi-agent system(MAS)has attracted plenty of researchers in various fields[1,2].Different from multi-agent consensus or synchronization,multi-agent coverage control cares about how to coordinate a team of agents for effectively monitoring or covering a given terrain,which inevitably gives rise to the interaction between individual dynamics and external environments.Nevertheless,environmental uncertainties that include static uncertainties and dynamic uncertainties and limited sensing capabilities of a single agent make it a great challenge to design control algorithms of MAS for achieving the desired coverage performance.

Impeded degradation of perovskite solar cells via the dual interfacial modification of siloxane

It is challenging to improve the long-term stability of perovskite solar cells(PSCs) without sacrificing efficiency. The perovskite absorbers degrade from the film surface/interfaces, which follows entangled mechanisms that have not been fully revealed yet.Herein, we decouple and elaborate two distinctive pathways regarding film degradation based on FACsPbI3perovskites.Moreover, a dual interfacial modification strategy has been developed for improving the material’s intrinsic stability, thus leading to the film degrading in a more retardant pathway. The corresponding PSCs achieve a stable power output efficiency of 23.75%.More importantly, the unencapsulated PSCs devices retain over 93% of their initial PCE after the maximum power point(MPP)tracking under the continuous 1-sun illumination and show significantly improved stability after aged under the thermal treatment or stored in ambient atmosphere for over 1500 hours without obvious PCE decay. This work shows the importance of modulating the degradation pathway on stability improvement, and at the same time, proposes a strategy for designing perovskite-based optoelectronics with excellent performance and stability.

Nitric oxide-releasing polyurethane/S-nitrosated keratin mats for accelerating wound healing

Nitric oxide(NO)plays an important role in wound healing,due to its ability to contract wound surfaces,dilate blood vessels,participate in inflammation as well as promote collagen synthesis,angiogenesis and fibroblast proliferation.Herein,keratin was first nitrosated to afford S-nitrosated keratin(KSNO).As a NO donor,KSNO was then co-electrospun with polyurethane(PU).These as-spun PU/KSNO biocomposite mats could release NO sustainably for 72 h,matching the renewal time of the wound dressing.Moreover,these mats exhibited excellent cytocompatibility with good cell adhesion and cell migration.Further,the biocomposite mats exhibited antibacterial properties without inducing severe inflammatory responses.The wound repair in vivo demonstrated that these mats accelerated wound healing by promoting tissue formation,collagen deposition,cell migration,re-epithelialization and angiogenesis.Overall,PU/KSNO mats may be promising candidates for wound dressing.

Interfacial Engineering for Improved Stability of Flexible Perovskite Solar Cells

Because of unique optoelectronic properties,such as extended carrier lifetime,large absorption coefficient,high defect tolerance factor,low exciton binding energy,and ambipolar diffusion,metal halide perovskites display enormous potential for the next generation of photovoltaics.Flexible perovskite solar cells with low weight,high flexibility,and conformability have attracted attention for portable electronic products.The interface is crucial in perovskite solar cells for both photovoltaic efficiency and operational stability.A high-quality interface could be obtained through interface engineering.Here,we summarize the degradation mechanisms and review interfacial engineering with the emphasis on their effects in flexible perovskite solar cells.On the basis of recent research progress in flexible devices,current challenges,possible directions,and perspectives are discussed.This would be helpful to promote the commercialization of flexible perovskite solar cells.