Frontier applications of perovskites beyond photovoltaics

Perovskites have been widely utilized as active materials in various optoelectronic devices, e.g. light-emitting diodes(LEDs), photodetectors(PDs), and solar cells(SCs), etc., due to their facile processability and outstanding optoelectronic properties.

Detection and surveillance of circulating tumor cells in osteosarcoma for predicting therapy response and prognosis

Objective:Osteosarcoma(OS)is an aggressive,highly metastatic,relatively drug-resistant bone tumor with poor long-term survival rates.The presence and persistence of circulating tumor cells(CTCs)in the peripheral blood are believed to be associated with treatment inefficiency and distant metastases.A blood-based CTC test is thus greatly needed for monitoring disease progression and predicting clinical outcomes.However,traditional methods cannot detect CTCs from tumors of mesenchymal origin such as OS,and research on CTC detection in mesenchymal tumors has been hindered for years.Methods:In this study,we developed a CTC test based on hexokinase 2,a metabolic function-associated marker,for the detection and surveillance of OS CTCs,and subsequently explored its clinical value.Twelve patients with OS were enrolled as the training cohort for serial CTC tests.Dynamic CTC counting,in combination with therapy evaluation and post-treatment follow-up,was used to establish a model for predicting post-chemotherapy evaluation and disease-free survival,and the model was further validated with a cohort of 8 patients with OS.Results:Two dynamic CTC number patterns were identified,and the resulting predictive model exhibited 92%consistency with the clinical outcomes.This model suggested that a single CTC test has similar predictive power to serial CTC analysis.In the validation cohort,the single CTC test exhibited 100%and 87.5%consistency with therapy response and disease-free survival,respectively.Conclusions:Our non-invasive test for detection and surveillance of CTCs enables accurate prediction of therapy efficiency and prognosis,and may be clinically valuable for avoiding inefficient therapy and prolonging survival.

Alternative splicing and related RNA binding proteins in human health and disease

Alternative splicing(AS)serves as a pivotal mechanism in transcriptional regulation,engendering transcript diversity,and modifications in protein structure and functionality.Across varying tissues,developmental stages,or under specific conditions,AS gives rise to distinct splice isoforms.This implies that these isoforms possess unique temporal and spatial roles,thereby associating AS with standard biological activities and diseases.Among these,AS-related RNA-binding proteins(RBPs)play an instrumental role in regulating alternative splicing events.Under physiological conditions,the diversity of proteins mediated by AS influences the structure,function,interaction,and localization of proteins,thereby participating in the differentiation and development of an array of tissues and organs.Under pathological conditions,alterations in AS are linked with various diseases,particularly cancer.These changes can lead to modifications in gene splicing patterns,culminating in changes or loss of protein functionality.For instance,in cancer,abnormalities in AS and RBPs may result in aberrant expression of cancer-associated genes,thereby promoting the onset and progression of tumors.AS and RBPs are also associated with numerous neurodegenerative diseases and autoimmune diseases.Consequently,the study of AS across different tissues holds significant value.This review provides a detailed account of the recent advancements in the study of alternative splicing and AS-related RNA-binding proteins in tissue development and diseases,which aids in deepening the understanding of gene expression complexity and offers new insights and methodologies for precision medicine.

Wafer-scale patterned growth of type-II Dirac semimetal platinum ditelluride for sensitive room-temperature terahertz photodetection

As the lastly unexplored electromagnetic wave,terahertz(THz)radiation has been exploited in a plenty of contexts such as fundamental research,military and civil fields.Most recently,representative two-dimensional(2D)topological semimetal,platinum ditelluride(PtTe_(2))has attracted considerable research interest in THz detection due to its unique physical properties.However,to achieve practical applications,the low-cost,large-scale,controllable synthesis and efficient patterning of 2D materials are key requirements,which remain a challenge for PtTe_(2)and its photodetectors(PDs).Herein,a facile approach is developed to obtain waferscale(2-inches)patterned PtTe_(2)arrays using one-step tellurium-vapor transformation method and micro-Nano technology.PtTe_(2)PD arrays are fabricated with the as-grown PtTe_(2)arrays evenly distributed on a 2-inch wafer,exhibiting high conductivity(~2.7×105 S m^(-1))and good electrical consistency.Driven by the Dirac fermions,PtTe_(2)PDs achieve a broadband(0.02-0.3 THz)response with a fast response speed(~4.7μs),a high sensitivity(~47 pW Hz^(-1/2))and high-resolution transmission THz-imaging capability,which displays the potential of large-area THz array imaging.These results are one step towards the practical applications of integrated PD arrays based on 2D materials.

Boosting the efficiency of quantum dot–sensitized solar cells over 15%through light-harvesting enhancement

How to improve the capacity of light-harvesting is still an important point and essential strategy for the assembling of high-efficiency quantum dot–sensitized solar cells(QDSCs).A believable approach is to implant new light absorption materials into QDSCs to stimulate the charge transfer.Herein,the few-layer black phosphorus quantum dots(BPQDs)are synthesized by electrochemical intercalation technology using bulk BP as source.Then the obtained BPQDs are deposited onto the surface of Zn–Cu–In–S–Se(ZCISSe)QD-sensitized TiO2 substrate to serve as another light-harvesting material for the first time.The experimental results have shown that BPQDs can not only increase the absorption intensity by photoanode but also reduce unnecessary charge recombination processes at the interface of photoanode/electrolyte.Through optimizing the size and deposition process of BPQDs,the champion power conversion efficiency of ZCISSe QDSCs is increased to 15.66%(26.88 mA/cm2,Voc=0.816 V,fill factor[FF]=0.714)when compared with the original value of 14.11%(Jsc=25.41 mA/cm^(2),Voc=0.779 V,FF=0.713).

Highly stable and repeatable femtosecond soliton pulse generation from saturable absorbers based on twodimensional Cu3-xP nanocrystals

Heavily doped colloidal plasmonic nanocrystals have attracted great attention because of their lower and adjustable free carrier densities and tunable localized surface plasmonic resonance bands in the spectral range from near-infra to mid-infra wavelengths.With its plasmon-enhanced optical nonlinearity,this new family of plasmonic materials shows a huge potential for nonlinear optical applications,such as ultrafast switching,nonlinear sensing,and pulse laser generation.Cu3-xP nanocrystals were previously shown to have a strong saturable absorption at the plasmonic resonance,which enabled high-energy Q-switched fiber lasers with 6.1μs pulse duration.This work demonstrates that both high-quality mode-locked and Q-switched pulses at 1560 nm can be generated by evanescently incorporating two-dimensional(2D)Cu3-xP nanocrystals onto a D-shaped optical fiber as an effective saturable absorber.The 3 dB bandwidth of the mode-locking optical spectrum is as broad as 7.3 nm,and the corresponding pulse duration can reach 423 fs.The repetition rate of the Q-switching pulses is higher than 80 kHz.Moreover,the largest pulse energy is more than 120μJ.Note that laser characteristics are highly stable and repeatable based on the results of over 20 devices.This work may trigger further investigations on heavily doped plasmonic 2D nanocrystals as a next-generation,inexpensive,and solution-processed element for fascinating photonics and optoelectronics applications.

Probing the dynamic structural changes of DNA using ultrafast laser pulse in graphene-based optofluidic device

The ultrafast monitoring of deoxyribonucleic acid(DNA)dynamic structural changes is an emerging and rapidly growing research topic in biotechnology.The existing optical spectroscopy used to identify different dynamical DNA structures lacks quick response while requiring large consumption of samples and bulky instrumental facilities.It is highly demanded to develop an ultrafast technique that monitors DNA structural changes with the external stimulus or cancer-related disease scenarios.Here,we demonstrate a novel photonic integrated graphene-optofluidic device to monitor DNA structural changes with the ultrafast response time.Our approach is featured with an effective and straightforward design of decoding the electronic structure change of graphene induced by its interactions with DNAs in different conformations using ultrafast nanosecond pulse laser and achieving refractive index sensitivity of~3×10^(−5) RIU.This innovative technique for the first time allows us to perform ultrafast monitoring of the conformational changes of special DNA molecules structures,including G-quadruplex formation by K+ions and i-motif formation by the low pH stimulus.The graphene-optofluidic device as presented here provides a new class of label-free,ultrafast,ultrasensitive,compact,and cost-effective optical biosensors for medical and healthcare applications.

High tolerance detour-phase graphene-oxide flat lens

Flat lenses thinner than a wavelength promise to replace conventional refractive lenses in miniaturized optical systems.However,Fresnel zone plate flat lens designs require dense annuli,which significantly challenges nanofabrication resolution.Herein,we propose a new implementation of detour phase graphene flat lens with flexible annular number and width.Several graphene metalenses demonstrated that with a flexible selection of the line density and width,the metalenses can achieve the same focal length without significant distortions.This will significantly weaken the requirement of the nanofabrication system which is important for the development of large-scale flat lenses in industry applications.

Interface and surface engineering of black phosphorus: a review for optoelectronic and photonic applications

Since being rediscovered as an emerging 2D material,black phosphorus(BP),with an extraordinary energy structure and unusually strong interlayer interactions,offers new opportunities for optoelectronics and photonics.However,due to the thin atomic body and the ease of degradation with water and oxides,BP is highly sensitive to the surrounding environment.Therefore,high-quality engineering of interfaces and surfaces plays an essential role in BP-based applications.In this review,begun with a review of properties of BP,different strategies of interface and surfaces engineering for high ON-OFF ratio,enhanced optical absorption,and fast optical response are reviewed and highlighted,and recent state-of-the-art advances on optoelectronic and photonic devices are demonstrated.Finally,the opportunities and challenges for future BP-related research are considered.