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The most studied thermoelectric element is tellurium (Te) because of its high Seebeck coefficient and low lattice thermal conductivity. Combining nanostructured Te with flexible polymers can be an effective strategy for flexible thermoelectrics.

Photodynamic therapy (PDT) is a highly promising modality against cancer, but its efficacy is severely limited by the low oxygen content in solid tumors. In this study, a smart photosensitive NiPS3 nanosheet was developed to solve the problem of low oxygen to allow PDT to be performed against tumors. The photosensitized ROS generation mechanism of NiPS3 is the photon-generated electron-hole pathway, which can generate O2 ·− and ·OH at the conduction band and valance band, respectively. More crucial is that ·OH generation doesn’t need O2, and the O2 ·− can also work in a low O2 environment, and depleting oxygen in tumor cells. Modified with triphenylphosphine (TPP) and based on density functional theory (DFT) calculations and experimental data, the NiPS3@TPP nano-system underwent targeted action toward mitochondria. In vitro experiments demonstrated that the reactive oxygen species (ROS) produced by NiPS3@TPP altered mitochondrial membrane permeability, which not only prolonged the PDT effect but also resulted in mitochondria apoptosis pathways inducing an apoptosis cascade. In vivo experiments demonstrated the targeting capability with low toxicity of the NiPS3@TPP nano-system. Tumor targeting at the tested dose indicated that it represented a promising biocompatible photosensitizer for in vivo biomedical applications.

Mesoporous carbon spheres (MCSs) are widely used in the field of pollutants adsorption, energy storage and various biomedicine applications such as targeted delivery vector, phototherapy sensitizers, bioimaging contrast agents, etc. Current synthetic strategies including soft templating and hard templating methods generally have the limits of using expensive surfactants or lack of control over the pore structures. Therefore, the complex and uncontrollable pore structures limit its further clinical application. Herein, we proposed a new synthetic strategy to control the uniformity of pore channel arrangement in MCSs which can modulate the photonic property and the corresponding light controlled drug release property in intelligent drug delivery. The as obtained MCSs with relative uniform pore channel arrangement and long pore channels are demonstrated to have the best NIR light-induced drug release performance. This work provides not only new synthetic method to modulate pore structure characteristics and biophotonic property of MCSs, but also uniform MCSs as novel delivery platforms with advanced controlled release performance.

Dynamics of photoinduced species, as a key parameter for nanomaterials plays a significantly role in the performance of optoelectronic devices. In this work, the origin of broadband optical response for the emerging Ti3C2T x MXene is revealed by transient spectroscopic analysis. From ultraviolet to infrared, the steady-state and transient optical responses present wavelength-related features. The carrier lifetime is found to change from femtosecond to nanosecond time scale dominated by various photoinduced species, i.e., carrier and surface plasmon. The unique optoelectronic character enables photodetection. This fundamental study on carrier, plasmon dynamics, and application in photodetection is helpful for exploring MXene-based optoelectronic devices.

International audience; The (100) surface of alpha-MoO3 (α-MoO3) should possess overwhelmingly more exposed Mo than the (010), and the exposed Mo has been extensively considered as active site for amine adsorption. However, α-MoO3 (100) has drawn little attention concerning amine sensing mechanism. In this research, adsorption of ammonia (NH3), monomethylamine (MMA), dimethylamine (DMA), and trimethylamine (TMA) is systematically investigated by density functional theory (DFT). All of these four molecules have high affinity to α-MoO3 (100) through interaction between the N and the exposed Mo, and the affinity is mainly influenced by number of methyl group and number of N-connected H. Adsorption and dissociation of water and oxygen molecule on stoichiometric or defective α-MoO3 (100) surface are then simulated to fully understand surface chemistry of α-MoO3 (100) in practical condition. At low temperature α-MoO3 (100) must be covered with lots of water molecule; the water can desorb or dissociate into hydroxyl groups at high temperature. Oxygen vacancy (VO) can be generated considering the annealing process during sensor device fabrication; VO must be filled with O2 molecule, which can further interact with adsorbed water nearby to form hydroxyl groups. According to this research, α-MoO3 (100) must be the active surface for amine sensing and its surface chemistry is well understood. In near future, further reaction and interaction will be simulated at α-MoO3 (100), and much more attention should be paid to α-MoO3 (100) not only theoretically but also experimentally.

Despite the emerging interest in research and development of Ti3CN MXene nanosheet (NS)-based optoelectronic devices, there is still a lack of in-depth studies of the underlying photophysical processes, like carrier relaxation dynamics and nonlinear photon absorption, operating in such devices, hindering their further and precise design. In this paper, we attempt to remedy the situation by fabricating few-layer Ti3CN NSs via combining selective etching and molecular intercalation and by investigating the carrier relaxation possesses and broadband nonlinear optical responses via transient absorption and Z-scan techniques. These results are complemented by first-principle theoretical analyses of the optical properties. Both saturable absorption and reverse saturable absorption phenomena are observed due to multiphoton absorption effects. The analysis of these results adds to the understanding of the basic photophysical processes, which is anticipated to be beneficial for the further design of MXene-based devices.

A novel noble-metal-free WO3@ZnIn2S4 heterojunction showed outstanding photocatalytic H2-production activity resulting from S-scheme electron/hole separation and a lower H2-evolution barrier as evidenced by DFT calculation, in situ XPS and TRPL.

Graphdiyne is a newly discovered two-dimensional planar carbon allotrope with highly π-conjugated interactions. This review aims to introduce graphdiyne and describe its similarities and differences with graphene to better understand the graphdiyne.

The detection of low-concentration ammonia is necessary to avoid harm to workers exposed to ammonia atmosphere for long period in the poultry farming and fertilizer industry. Transition metal dichalcogenides (TMDs) nanomaterials have shown good ability in ammonia sensing, while alloying TMDs (two chalcogenide or/and metal elements) with tunable electronic structures have drawn little attention in gas sensing. Herein, alloying Mo0.5W0.5S2 quantum dots (QDs) were prepared by a facile sonication exfoliation method and then for the first time tested for ammonia sensing. The crystal structure, geometric morphology, and elemental composition all proved well-alloyed Mo0.5W0.5S2 QDs. The gas sensing measurements demonstrated Mo0.5W0.5S2 QDs with good response to ammonia even at part per billion (ppb)-level near room temperature. The sensor also displayed good stability as well as superb selectivity to ammonia in the presence of potential interferences, such as methanol, acetone, benzene, and cyclohexane. The theoretical calculations revealed Mo and W atoms at edges (such as Mo0.5W0.5S2 (010)) of sheet-like QDs as the active sites for ammonia adsorption. Electrons donated by the adsorbed ammonia were combined with holes in p-type Mo0.5W0.5S2 QDs, and the concentration of the main charge carrier was reduced, resulting in resistance enhancement.

Uniform, well-defined cadmium sulfide@cadmium selenide core/shell quantum dots (CdS@CdSe QDs) were, for the first time, successfully synthesized by a solvothermal method and chemical bath growth for photoelectrochemical activities. The as-synthesized CdS@CdSe QDs not only exhibit superior self-powered photoresponse behavior and excellent stability under ambient conditions but also display significantly improved current densities and photoresponsivity compared to those of individual CdS QDs or CdSe QDs, mainly due to the built-in electric field, and thus have great potential in the fields of renewable energy and renewable energy consumption for carbon neutrality target achievement.

Owing to the distinctive constituents of tumor tissue from those healthy organs, nanomedicine strategies show significant potentials in smart drug delivery. Nowadays, stimuli-responsive nanogels are playing increasingly important roles in the application of cancer therapy because of their sensitivity to various internal or external physicochemical stimuli, which exhibit site-specific and markedly enhanced drug release. Besides, nanogels are promising as drug carriers because of their porous structures, good biocompatibility, large surface area, and excellent capability with drugs. Taking advantage of multiresponsiveness, recent years have witnessed the rapid evolution of stimulus-responsive nanogels from monoresponsive to multiresponsive systems; however, there lacks a comprehensive review summarizing these reports. In this Review, we discuss the properties, synthesis, and characterization of nanogels. Moreover, tumor microenvironment and corresponding designing strategies for stimuli-response nanogels, both exogenous (temperature, magnetic field, light) and endogenous (pH, biomolecular, redox, ROS, pressure, hypoxia) are summarized on the basis of the recent advances in multistimuli-responsive nanogel systems. Nanogel and two-dimensional material composites show excellent performance in the field of constructing multistimulus-responsive nanoparticles and precise intelligent drug release integrated system for multimodal cancer diagnosis and therapy. Finally, potential progresses and suggestions are provided for the further design of hybrid nanogels based on emerging two-dimensional materials.

Ti3C2Tx MXene has attracted remarkable attention due to its promising applications in energy storage and sensors. However, traditional MXene preparation methods used HF as etchant, which was highly toxic and harmful to human and environment. Moreover, the aqueous etchants will also result in the combination of OH, O and F groups on the surfaces, making it difficult to control the varieties and contents of the surface terminations. In this paper, a green and mild electrochemical exfoliation method was proposed to synthesize Ti3C2Fx and synchronously control its fluorination degree on the surface. A non-aqueous ionic liquid, [BMIM][PF6]-based solution was used as electrolyte. The as-prepared Ti3C2Fx was fluorinated with the CF and TiF3 groups, which were electrochemically active and contributed to the excellent cycling stability of the MXene anode-based Li-ion batteries. These findings provided a facile strategy to prepare MXene materials and dope MXene with tailored property for MXene-based energy devices applications.

Understanding the impact of bismuth cations on the optical properties of borosilicate glass is significant for manipulating borate glass applications. In this paper, the influence of bismuth cations on both structural and optical properties of borosilicate glass doped with NiO was investigated. Different glass samples, containing different amounts of Bi2O3 and a constant amount of NiO, were prepared and studied. Infrared (IR) analysis was carried out to study the internal structure within the investigated glass samples. Optical absorption studies were performed to investigate the impact of Bi2O3 content on optical properties of the BiBaNiB-glasses. Astonishingly, with Bi2O3 addition, an absorption band at 380 nm has appeared. Moreover, this band is overlapped with the Urbach edge; which regularly produced an artificial edge-like feature at ~450 nm. A detailed deconvolution protocol has been implemented for an appropriate understanding of these spectra and unraveling the hidden Urbach edge. Optical band gap energy, linear and nonlinear refractive index for each BiBaNiB sample were calculated. Furthermore, the metallization criterion was calculated to examine the metallic or insulating nature of the BiBaNiB-glasses. The values of the nonlinear third-order susceptibility and nonlinear refractive index were increased with Bi2O3 doping. The BiBaNiB-glasses exhibited outstanding stability and optical band gap than the pristine glass sample, which makes it possible for practical applications.

Poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) mixed with single-wall nanotubes (SWNTs) (10:1) and doped with (0.1 M) perchloric acid (HClO4) in a solution-processed film, working as an excellent thin transparent conducting film (TCF) in organic solar cells, was investigated. This new electrode structure can be an outstanding substitute for conventional indium tin oxide (ITO) for applications in flexible solar cells due to the potential of attaining high transparency with enhanced conductivity, good flexibility, and good durability via a low-cost process over a large area. In addition, solution-processed vanadium oxide (VOx) doped with a small amount of PEDOT-PSS(PH1000) can be applied as a hole transport layer (HTL) for achieving high efficiency and stability. From these viewpoints, we investigate the benefit of using printed SWNTs-PEDOT-PSS doped with HClO4 as a transparent conducting electrode in a flexible organic solar cell. Additionally, we applied a VOx-PEDOT-PSS thin film as a hole transporting layer and a blend of PTB7 (polythieno[3,4-b] thiophene/benzodithiophene): PC71BM (phenyl-C71-butyric acid methyl ester) as an active layer in devices. Zinc oxide (ZnO) nanoparticles were applied as an electron transport layer and Ag was used as the top electrode. The proposed solar cell structure showed an enhancement in short-circuit current, power conversion efficiency, and stability relative to a conventional cell based on ITO. This result suggests a great carrier injection throughout the interfacial layer, high conductivity and transparency, as well as firm adherence for the new electrode.

Poor conductivity and rate capability are the obstacles faced by nickel-cobalt composites as electrode materials for supercapacitor application. Herein, simple electrochemical treatment conducted by cyclic voltammetry is applied and the overall performance of the active material is considerably enhanced. We discover that this treatment triggers the formation of Ni-Co-Cu ternary composite and optimizes the crystal structure of the untreated counterpart. The areal capacitance of the treated sample rockets up to 6.13 F cm−2 at 2 mA cm−2, almost 13 times higher than the untreated ones. Besides, the resistance is substantially reduced by cyclic voltammetry treatment. Moreover, the Coulombic efficiency and stability are concurrently elevated. The reasons behind this treatment are mulled over and reasonable hypothesis is suggested. This study provides a cheap and effortless way to reform the structures of as-obtained samples as well as vigorously raise the performance of current available materials.

CdS semiconductor nanocrystals have been prepared in novel glass matrix. DTA curve was analyzed to evaluate the glass transition temperature and hence determine the heat treatment temperatures of samples. The existence of the CdS semiconductor as nanocrystallites was confirmed by XRD, TEM and FTIR spectra analyses. The growth of CdS semiconductor nanocrystals in glass matrix was investigated through the analysis of optical absorption spectroscopy. The spectra indicate that the absorption edges shift toward longer wavelengths after increasing the heat-treated temperatures and times. The blueshifts of the absorption edges were used to calculate the CdS particle sizes by effective mass approximation. The present glass includes CdS nanocrystals with an initial size of ~ 1.41 nm on cooling from the melt at ~ 1100 °C to room temperature. The activation energy for the early stages of diffusive growth of CdS nanocrystals in present glass is obtained by Arrhenius plots to be 49.37 kJ/mol.

Supercapacitors are deemed as reliable power sources for portable devices and electric vehicles. Electrode materials with high energy and power densities are greatly needed. Herein, we designed reduced-graphene-oxide supported nickel-cobalt layered double hydroxide nanosheets (NiCo-LDH/rGO) as electrode materials. The introduction of graphene could largely enhance the conductivity, and the supported NiCo-LDH could effectively prevent graphene from self-aggregation. Thanks to the synergistic effect of conductive graphene and electro-active LDH, the nanocomposites delivered a capacitance of 1675 F g−1 at 1 A g−1 and decent rate performance (capacitance retention of 83.8% at 10 A g−1); while NiCo-LDH could only exhibited a capacitance of 920 F g−1 at 1 A g−1 and 81.5% of the capacitance remained at 10 A g−1. The asymmetric supercapacitors assembled with NiCo-LDH/rGO and activated carbon (AC) delivered high energy density and power density, up to 49.9 Wh kg−1 and 3747.9 W kg−1, respectively. The appealing electrochemical performance indicates its huge application potential in supercapacitors.

The current effort aims at the morphological displays of TiO2 materials grown on Ti foil substrates using aerosol assisted chemical vapour deposition. Optimization of temperature, surfactant concentrations and substrate orientation has been found to play a vital role in the smart designing of micro/nanostructures, ranging from microspheres, nanopetals, nanospikes to the nanorods. Interestingly, when tested as LIB anode these various morphologies showed a much distinct performance and stability during charge/discharge cycles. The nanorod structures with smooth carbon covering have shown excellent reversibility followed by the nano-petals that showed an impressively stable capacity.

This investigation addressed Phoenix dactylifera biodiesel (PDME) production using an ultrasound-assisted transesterification process. The produced Phoenix dactylifera biodiesel (PDME25) was blended with different concentrations of multiwalled carbon nanotubes and titanium dioxide (TiO2). Diethyl ether (DEE, 1% vol.) and sorbitan oleate (Span80, 2% vol.) surfactants were used to enhance and stabilize nanoparticles for the physiochemical properties in the base fluids. The piston bowl geometry was modified to a toroidal type for better swirl and squish motion, and a six-hole fuel injector was used for enhanced atomization. The BTE and HRR improved by 22.9% and 20.1%, respectively, while the CO, HC, smoke emissions, BSFC, and ignition delay decreased by 32.8%, 23.8%, 13.4%, 25.2%, and 19.08%, respectively. The results showed that the blend of potential biodiesel sources, viz. Phoenix dactylifera and MWCNT–TiO2 nanoadditives, delivered comparable diesel fuel properties.

Step-scheme heterojunctions formed between two firmly bound photocatalysts facilitate charge separation due to interfacial charge transfer, which is usually illustrated by the gain or loss of electrons in the constituent photocatalysts characterized by in situ irradiated X-ray photoelectron spectroscopy. This technique provides a steady-state view of charge distribution but overlooks the transient and complex dynamics of charge transfer, trapping, and recombination. To provide a molecular-level and dynamic view of these processes, we investigated the behaviors of photogenerated charge carriers within an inorganic/organic TiO

The outbreak of the COVID-19 pandemic was partially due to the challenge of identifying asymptomatic and presymptomatic carriers of the virus, and thus highlights a strong motivation for diagnostics with high sensitivity that can be rapidly deployed. On the other hand, several concerning SARS-CoV-2 variants, including Omicron, are required to be identified as soon as the samples are identified as ‘positive’. Unfortunately, a traditional PCR test does not allow their specific identification. Herein, for the first time, we have developed MOPCS (Methodologies of Photonic CRISPR Sensing), which combines an optical sensing technology-surface plasmon resonance (SPR) with the ‘gene scissors’ clustered regularly interspaced short palindromic repeat (CRISPR) technique to achieve both high sensitivity and specificity when it comes to measurement of viral variants. MOPCS is a low-cost, CRISPR/Cas12a-system-empowered SPR gene-detecting platform that can analyze viral RNA, without the need for amplification, within 38 min from sample input to results output, and achieve a limit of detection of 15 fM. MOPCS achieves a highly sensitive analysis of SARS-CoV-2, and mutations appear in variants B.1.617.2 (Delta), B.1.1.529 (Omicron) and BA.1 (a subtype of Omicron). This platform was also used to analyze some recently collected patient samples from a local outbreak in China, identified by the Centers for Disease Control and Prevention. This innovative CRISPR-empowered SPR platform will further contribute to the fast, sensitive and accurate detection of target nucleic acid sequences with single-base mutations.

The present search handles the blue light emission investigation of hybrid quantum dots organic light-emitting devices. The emissions at 445 nm and 460 nm have been examined for microcavity hybrid quantum dot organic light-emitting devices (QD-OLED) upon quantum dots of CdS and CdSe. External light emissions have been evaluated through a numerical model based on the transfer matrix for electromagnetic plane waves. The devices' optical properties are investigated based on internal reflectance and cavity length by considering the architecture consisting of multilayers thin-film structures. The overall performance of the light-emitting devices with emission at 445 nm showed an improvement of the enhancement factor and narrowing outcoupling emission relative to the devices with emission at 460 nm. Besides, the light-emitting devices based on CdS QDs revealed better performance relative to the devices based on CdSe QDs.