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A self-assembled dipole interface monolayer is a possible strategy to obtain efficient and bright green InP quantum dot light-emitting diodes.

One-dimensional semiconductor-metal heterostructures manifest improved charge separation capability, tunable band gap and increased surface area, and have been regarded as promising photocatalysts for solar-to-fuel conversion through water splitting. We herein review the synthetic strategies for the rational design and preparation of one-dimensional semiconductor-metal heterostructures with precise control in terms of size, shape, composition and function. Approaches that are capable of improving the photocatalytic performance of one-dimensional semiconductor-metal heterostructures have been proposed and analyzed The present work is expected to give the rational design of one-dimensional semiconductor-metal heterostructures and provide insights into accomplishing highly efficient photocatalysis based on such materials

Nickel oxyhydroxide (NiOOH) is regarded as one of the promising cocatalysts to enhance the catalytic performance of photoanodes but suffers from serious interfacial charge-carrier recombination at the photoanode||NiOOH interface. In this work, surface-engineered BiVO4 photoanodes are fabricated by sandwiching an oxygen vacancy (Ovac) interlayer between BiVO4 and NiOOH. The surface Ovac interlayer is introduced on BiVO4 by a chemical reduction treatment using a mild reducing agent, sodium hypophosphite. The induced Ovac can alleviate the interfacial charge-carrier recombination at the BiVO4||NiOOH junction, resulting in efficient charge separation and transfer efficiencies, while an outer NiOOH layer is coated to prevent the Ovac layer from degradation. As a result, the as-prepared NiOOH-P-BiVO4 photoanode exhibits a high photocurrent density of 3.2 mA cm−2 at 1.23 V vs. RHE under the irradiation of 100 mW/cm2 AM 1.5G simulated sunlight, in comparison to those of bare BiVO4, P-BiVO4, and NiOOH-BiVO4 photoanodes (1.1, 2.1 and 2.3 mA cm−2, respectively). In addition to the superior photoactivity, the 5-h amperometric measurements illustrate improved stability of the surface-engineered NiOOH-P-BiVO4 photoanode. Our work showcases the feasibility of combining cocatalysts with Ovac, for improved photoactivity and stability of photoelectrodes.

Lead-free hybrid perovskites (LFHPs) have sparked considerable research interest in photocatalysis. This review introduces the surface engineering and photophysical behaviors of LFHPs for diverse solar-induced photocatalytic applications.

Metal halide perovskites, as a new generation of semiconductor materials, have been widely applied in various optoelectronic devices, especially in the field of perovskite light-emitting diodes (PeLEDs). The external quantum efficiencies (EQEs) of green, red, and near-infrared PeLEDs have exceeded 20% for the last few years, which are comparable to those of the state-of-the-art organic light-emitting diodes (OLEDs) and quantum-dot light-emitting diodes (QLEDs). However, the performances of blue PeLEDs lag far behind those of their counterparts, presumably due to the low quantum yields of blue perovskite films, the instability of the emission spectra, and the difficulties in charge injection for the devices under operation conditions. In this review, the structures and physical properties of blue emissive perovskite materials and the preparation methods of the corresponding perovskite films are firstly addressed. Then, the recent advances and strategies to improve the efficiency of blue PeLEDs are outlined, and the main challenges faced with the blue PeLEDs are also discussed. Finally, an outlook on blue LEDs based on perovskite materials is proposed.

Achieving bright photon upconversion under low irradiance is of great significance and finds many stimulating applications from photovoltaics to biophotonics. However, it remains a daunting challenge to significantly intensify upconversion luminescence in small nanoparticles with a simple structure. Herein, we report the amplification of photon upconversion through engineering interfacial density of states between the core and the shell layer in sub-10 nm colloidal rare-earth ions doped fluoride nanocrystals. Through tuning of the metal cations in the shell layer of alkaline-earth-based core/shell nanoparticles, both the interfacial phonon frequency and the density of state are evidently decreased, resulting in the luminescence intensification of up to 8224 times. The generality of this upconversion enhancement strategy has been verified through expansion of this approach to alkali-based core/shell nanoparticles. The engineering of photon density of state in such core/shell nanoparticles enables dynamic display and high-level security information storage.

Nanorod-like CoP nanoparticles were fabricated from different precursors of Co(OH)2 and Co3O4 by gas-solid reaction, then further embedded into g-C3N4 nanosheets to form intimate heterojunctions via the (0 1 1) crystal planes of CoP nanoparticles. The heterojunction hybrid obtained from Co(OH)2 exhibits superior activity in photo, electro and photoelectrochemical water splitting processes. In photocatalytic water half-splitting for hydrogen evolution reaction, the as-obtained 0.5% CoP-CN achieved a rate at 959.4 μmol·h−1·g−1 and 59.1 μmol·h−1·g−1 when irradiated by simulated sunlight and visible light respectively, almost 3.1 times and 15.8 times that of pristine g-C3N4, For photocatalytic water full-splitting, a stoichiometric evolution of H2 (14.7 μmol·h−1·g−1) and O2 (7.6 μmol·h−1·g−1) was observed on 3%Pt-0.5% CoP-CN composite. The onset potential for electrochemical HER process was drastically reduced after deposition with 0.5% CoP. Meanwhile, a higher photocurrent response and larger anodic photocurrent was detected over 0.5% CoP-CN photoanode during the photoelectrochemical water splitting process, relative to pristine g-C3N4 and its analogues. The comprehensive enhancements for catalytic activity of 0.5% CoP-CN could be attributed to its reduced over-potentials, more negative photo-reductive potentials, boosted interfacial charge transfer efficiency, as well as a much higher solar to hydrogen efficiency. The contrastive redox roles of CoP in both photocatalytic water half-splitting and full-splitting processes have been fully explored and revealed. This design on covalent organic framework of highly efficient CoP-based heterojunctions holds great promise for direct water splitting applications in utilizing solar energy.

This study aims to investigate the characteristics of the phenotype and management of chronic obstructive pulmonary disease (COPD) patients in the general population in China. We analyzed spirometry-confirmed COPD patients who were identified from a population-based, nationally representative sample in China. All participants were measured with airflow limitation severity based on post-bronchodilator FEV1 percent predicted, bronchodilator responsiveness, exacerbation history, and respiratory symptoms. Among a total of 9134 COPD patients, 90.3% were non-exacerbators, 2.9% were frequent exacerbators without chronic bronchitis, 2.0% were frequent exacerbators with chronic bronchitis, and 4.8% were asthma-COPD overlap. Less than 5% of non-exacerbators ever had pulmonary function testing performed. The utilization rate of inhaled medication in non-exacerbators, exacerbators without chronic bronchitis, exacerbators with chronic bronchitis, and asthma-COPD overlap was 1.4, 23.5, 29.5, and 19.4%, respectively. A comprehensive strategy for the management of COPD patients based on phenotype in primary care is urgently needed.

The effective separation of photogenerated carriers plays a vital role in photocatalytic reactions. In addition to the intrinsic driving force of photocatalysis, an external field generating an enh...

Homogeneous photocatalysis has considerably contributed to green applications such as energy production and environmental decontamination. Currently, researchers mainly focus on the search for sustainable processes that can generate valuable chemical compounds with high selectivity and aid in the complete mineralization of hazardous compounds. Although homogeneous photocatalysts exhibit superior performance, their recovery after the reaction is difficult. The 3Rs process, i.e., recovery, recycling and reuse of photocatalysts respectively, is critical to make a photocatalytic process eco-friendly. Heterogenization of homogeneous photocatalysts is considered as an effective method to not only realize the recycling of homogeneous photocatalysts, but also enhance the overall photocatalytic activity. Conventional methods have employed synthetic materials for the heterogenization of homogeneous photocatalysts. Nevertheless, scientists have discovered that natural polymer sources can be alternatives due to their excellent chemical, mechanical, and electrical properties for applications under harsh reaction conditions. In this review, we have summarized state-of-the-art techniques employed for the heterogenization of homogeneous photocatalysts using various supporting materials in terms of design and preparation. First, we have organized these strategies into different categories, such as microporous encapsulation, dye-sensitized semiconductors, metal–organic framework (MOF) construction, carbon material fixation, synthetic polymer attachment and natural origin supports. To provide readers with deeper insights into this field, we have presented some fundamentals of homogeneous photocatalysis with respect to environmental applications and its heterogeneous strategies. Furthermore, we have discussed the performance of heterogeneous photocatalysts prepared from these methods, including photocatalytic performance, product selectivity and reusability. Finally, we have concluded with different aspects on the current challenges and new aspects in emerging technologies.

Ammonia (NH3) is essential to serve as the biological building blocks for maintaining organism function, and as the indispensable nitrogenous fertilizers for increasing the yield of nutritious crops. The current Haber–Bosch process for industrial NH3 production is highly energy- and capital-intensive. In light of this, the electroreduction of nitrogen (N2) into valuable NH3, as an alternative, offers a sustainable pathway for the Haber–Bosch transition, because it utilizes renewable electricity and operates under ambient conditions. Identifying highly efficient electrocatalysts remains the priority in the electrochemical nitrogen reduction reaction (NRR), marking superior selectivity, activity, and stability. Two-dimensional (2D) nanomaterials with sufficient exposed active sites, high specific surface area, good conductivity, rich surface defects, and easily tunable electronic properties hold great promise for the adsorption and activation of nitrogen towards sustainable NRR. Therefore, this Review focuses on the fundamental principles and the key metrics being pursued in NRR. Based on the fundamental understanding, the recent efforts devoted to engineering protocols for constructing 2D electrocatalysts towards NRR are presented. Then, the state-of-the-art 2D electrocatalysts for N2 reduction to NH3 are summarized, aiming at providing a comprehensive overview of the structure-performance relationships of 2D electrocatalysts towards NRR. Finally, we propose the challenges and future outlook in this prospective area.

The synthesis of ammonia via the Haber–Bosch process requires high temperature and high pressure, which causes about 1.6% of global CO2 emission every year. the development of a low-cost, facile ammonia synthesis method under ambient conditions is urgently required. Herein, we employed a facile approach to prepare defective g-C3N4 nanorods with a narrower bandgap and a sub-gap, which can significantly enhance the light utilization ratio. More importantly, the defects of g-C3N4 nanorods can also enhance the light adsorption and boost cleavage of N2 molecules, which is the rate-determining step of nitrogen fixation. Compared with bulk g-C3N4, the photocatalytic N2 reduction rate of defective g-C3N4 nanorods as the catalysts was increased by 3.66 times. According to the density functional theory calculation results, the active sites should be an extra carbon in the ring formed in s-triazine rings. This work may provide in-depth insights into the development of novel defective photocatalysts for N2 fixation.

Organic and/or inorganic halide perovskites have become a new class of optoelectronic materials by virtue of excellent attractive physical and chemical characteristics. In this context, the zero-dimensional (0-D) cesium lead bromide (Cs4PbBr6) perovskite with outstanding photoluminescence (PL) properties has been recognized as the most promising candidate. However, the electron transfer dynamics and electrochemical behaviors of Cs4PbBr6 emitters still remain unclear. Herein, we prepared the 0-D Cs4PbBr6 perovskite emitters and investigated the exciton transport and electrochemical dynamics by utilizing temperature-dependent transient photoluminescence (TRPL) and electrogenerated chemiluminescence (ECL) techniques, respectively. Stronger electronic coupling of Cs4PbBr6 emitters arises from the overlap of electronic wavefunctions, indicating the increased possibility for the generation of electrochemiluminescence. Through the determination of the diffusion coefficient and electron-transfer rate by using an electrochemical method, we confirm that effective heterogeneous charge transfer at the interface of the electrode and electrolyte results in red-shifted ECL emission in the presence of benzoyl peroxide (BPO) as the co-reactant. The development of zero-dimensional perovskite emitters opens up a new avenue in the field of emerging optoelectronic and biosensing technologies, including but not limited to ECL devices, ECL immunoassays, organic light-emitting diodes, light-emitting electrochemical cells, and other bio-related detections.

Correction for ‘Atomically flat semiconductor nanoplatelets for light-emitting applications’ by Bing Bai et al., Chem. Soc. Rev., 2023, 52, 318–360, https://doi.org/10.1039/D2CS00130F.

Thyroid Hürthle cell carcinoma, known as thyroid eosinophilic carcinoma, is a rare pathological type of differentiated thyroid cancer (DTC), representing 3-4% of all thyroid cancers. However, given the high risk of invasion and metastasis, thyroid Hürthle cell carcinoma has a relatively poor prognosis. Traditional treatment methods have limited effects on patients with metastatic thyroid cancers. Developing a valuable therapy for advanced thyroid carcinomas is an unfilled need, and immunotherapy could represent another choice for these tumors. We herein reported the case of a patient with recurrent advanced thyroid Hürthle cell cancer and positive programmed death-ligand 1 (PD-L1) expression, who suffered tumor progression after re-surgery, radiotherapy, and targeted therapy. It is encouraging that PD-1 inhibitors in combination with GM-CSF and stereotactic body irradiation (SBRT) on metastatic disease have a significant anti-tumor effect.

An environmentally friendly mixed-halide perovskite MA

Nickel oxyhydroxide (NiOOH) is regarded as one of the promising cocatalysts to enhance the catalytic performance of photoanodes but suffers from serious interfacial charge-carrier recombination at the photoanode||NiOOH interface. In this work, surface-engineered BiVO

© 2019, Tsinghua University Press and Springer-Verlag GmbH Germany, part of Springer Nature. As a metal-free semiconductor, graphitic carbon nitride (g-C3N4) has received extensive attention due to its high stability, nontoxicity, facile and low-cost synthesis, appropriate band gap in the visible spectral range and wide availability of resources. The dimensions of g-C3N4 can influence the regime of the confinement of electrons, and consequently, g-C3N4 with various dimensionalities shows different properties, making them available for many stimulating applications. Although there are some reviews focusing on the synthesis strategy and applications of g-C3N4, there is still a lack of comprehensive review that systemically summarises the synthesis and application of different dimensions of g-C3N4, which can provide an important theoretical and practical basis for the development of g-C3N4 with different dimensionalities and maximises their potential in diverse applications. By reviewing the latest progress of g-C3N4 studies, we aim to summarise the preparation of g-C3N4 with different dimensionalities using various structural engineering strategies, discuss the fundamental bottlenecks of currently existing methods and their solution strategies, and explore their applications in energy and environmental applications. Furthermore, it also puts forward the views on the future research direction of these unique materials. [Figure not available: see fulltext.]

With intrinsically disordered atomic structure, metallic glasses (MGs) have been extensively studied as advanced catalysts. Although the nature of widely tunable atomic composition in MGs facilitates accommodation in different catalytic environments, it may also induce the decline of catalytic activity due to surface effect. The role of surface of MGs is still not fully understood. In this work, an Fe50Ni30P13C7 (FeNiPC) glassy ribbon was found to have a strong-binding surface layer with the superior anticorrosion but low catalytic ability. Nevertheless, an effective elimination of surface layer by chemical dealloying could highly promote the catalytic ability of FeNiPC glassy ribbons from 20 min to only 10 min for brilliant black BN dye degradation. Further investigation revealed that chemical dealloying could effectively dissolve the surface layer of FeNiPC glassy ribbons induced reactivation of surface that was previously buried under the strong oxide layer, instead of generating nano-porous structured surface. The reactivation of ribbon surface effectively optimized active reaction sites and the re-exposure of Fe, Ni and P with zero-valent state formed galvanic cells by atomic clusters leading to the acceleration of catalysis. The insight and revelation of intrinsic surface activity in this work provide an effective way to highly promote the catalytic ability of MGs.

One-dimensional (1D) semiconductor nanorods are important for numerous applications ranging from optics and electronics to biology, yet the direct synthesis of high-quality metal halide perovskite nanorods remains a challenge. Here, we develop an intermediate monomer reservoir synthetic strategy to realize the controllable growth of uniform and low-defect CsPbBr3 perovskite nanorods. Intermediates composed of CsPb2Br5 and Cs3In2Br9 are obtained through the substitution of Pb2+ with In3+ cations in the template of CsPbBr3 nanocubes and act as a precursor reservoir to gradually release monomers, ensuring both the slow growth rate and low defects of nanorods. We have used branched tris(diethylamino)phosphine as a ligand, which not only has unequal binding energies with different crystal faces to promote the orientation growth but also provides strong steric hindrance to shield the nanorods in solution. Because of minor amount of defects and an effective ligand passivation, in addition to significantly enhanced stability, the perovskite nanorods show a high photoluminescence quantum yield of up to 90% and exhibit a net mode gain of 980 cm-1, the latter being a record value among all the perovskite materials. An extremely low amplified spontaneous emission threshold of 7.5 μJ cm-2 is obtained under excitation by a nanosecond laser, which is comparable to that obtained using femtosecond lasers in other recent studies.

Colloidal semiconductor nanocrystals (NCs), especially cadmium (Cd)- and lead (Pb)-containing ones, have been proved to be the promising materials for photoelectronic energy conversion applications. However, the high toxicity and cost of these materials restrict their widespread use. Zinc (Zn)-containing colloidal semiconductor NCs are non-/less toxic and environmentally friendly materials, manifesting in stimulating optical and electronic properties with relevance to a broad scope of applications including light-emitting diodes (LEDs), sensors, photocatalysts, and more. In this Review, we elaborate on the shape control of Zn-containing colloidal semiconductor NCs achieved by a variety of wet-chemical synthetic approaches. Moreover, the formation of core-shell, doped, and hybrid structures based on Zn-containing colloidal semiconductor NCs allow for the optimization of their functionalities, which underpin stimulating photoelectronic energy conversion applications in quantum-dot LEDs (QLEDs), photodetectors, and photocatalysis. Zn-containing colloidal semiconductor NCs that combine the green chemistry with sustainable developments possess a bright future.

Hybrid nanomaterials offer increased flexibility to achieve heterostructures with controlled functionalities and predictable linkages owing to their synergistic interactions. Here, we have developed a synthetic strategy that produced hexagonal-shaped nanoplatelets (NPLs) of gold–pyrrhotite (Au–Fe7S8) with Au embedded inside them by means of a seeded growth method. Using thiol-capped Au nanoparticles (NPs) as a seed, heterogeneous nucleation of the iron precursor was facilitated, leading to the formation of Au–Fe7S8 NPLs. The injection temperature and surface ligand of the seed (Au) were two critical factors that determined the homogeneity and final morphology of the Au–Fe7S8 NPLs. This strategy was further expanded using Ag NPs as the seed to construct heterodimers, producing Ag2S–Fe7S8 heterostructures.

Electrically insulating objects gain a net electrical charge when brought in and out of contact. This phenomenon-triboelectricity-involves the flow of charged species, but conclusively establishing their nature has proven extremely difficult. Here, we demonstrate an almost linear relationship between a plastic sample's net negative charge and the amount of solution metal ions discharged to metallic particles with a coefficient of proportionality linked to its electron affinity (stability of anionic fragments). The maximum magnitude of reductive redox work is also material dependent: metallic particles grow to a larger extent over charged dielectrics that yield stable cationic fragments (smaller ionization energy). Importantly, the extent to which the sample can act as electron source greatly exceeds the net charging measured in a Faraday pail/electrometer set up, which brings direct evidence of triboeletricity being a mosaic of positive and negative charges rather than a homogeneous ensemble and defines for the first time their quantitative scope in electrochemistry.

Novel materials from self-assembled nanocrystals hold great promise for applications ranging from inorganic catalysis to bio-imaging. However, because of the inherent anisotropic properties, it is challenging to assemble one-dimensional (1D) nanorods into higher-order structures (e.g. 2D sheets or 3D networks) without any support. Here, we have developed a facile strategy for the direct self-assembly of 1D nanorods into free-standing 2D nanorafts with lateral dimensions up to several micrometers. As a general approach, 2D nanorafts with diverse compositions, e.g. MgF(2), WO(2), CdS, ZnS, and ZnSe nanorafts, have been fabricated from the assembly of their 1D building blocks. More importantly, these nanorafts show high stability even when dispersed in different solvents, making them suitable for various applications. Because of their high porosity and strong adsorption capability, MgF(2) nanorafts were investigated to illustrate the collective advantages generated from the assembly platform. Moreover, flexibility in the composition and structure of the building blocks demonstrated in this work will lead to next generation materials with rich functionalities.

Dimension, composition and configuration are the primary aspects of semiconductor based hybrid heterostructures that govern their properties. To achieve desired functionalities within a single nanoparticle system, numerous synthetic approaches are available which may be suitable for achieving the target combination but these can be complex and tedious. In this work, a simple seeded-growth approach was employed to obtain an iron oxide–gold–cadmium sulfide (Fe3O4–Au–CdS) heterotrimer with a unique morphology manifesting magnetic, plasmonic and semiconducting properties. In a straightforward two-step synthesis process, Au–Fe3O4 dimer was injected as a seed into the Cd precursor solution for the growth of one-dimensional (1D) kinked CdS-5 nanorods on it. The synthesized Fe3O4–Au–CdS heterotrimer was tested in photocatalytic water-reduction reaction, revealing its potential as a photocatalyst for the hydrogen evolution reaction (HER), where each domain within the heterotrimer played a distinct role including light absorption, charge separation and magnetic separation. A post-synthetic modification on the semiconductor part was also performed where kinked CdS nanorod was cation exchanged with Ag2S leading to the formation of another heterotrimer of Fe3O4–Au–Ag2S while retaining the same morphology and expanding the palette of heterotrimers.

Herein we demonstrated that the shape and phase of colloidal ZnSe nanocrystals can be spontaneously tuned through tailoring the selenium precursor reactivity in a phosphine-free reaction system. Selenium species with diverse reaction activities, i.e. Se22− or Se2−, were produced by the addition of different volumes of reductant superhydride (lithium triethylborohydride). Theoretical calculation of ΔGr indicates that superhydride-reduced Se22− is less active than Se2− for the reaction with a Zn precursor. Nanoparticle growth using Se22− produces wurtzite ZnSe nanorods whereas the reaction of more reactive Se2− with the zinc precursor leads to the formation of spherical zinc blende ZnSe nanodots. This work not only provides a facile synthetic approach for the preparation of high quality ZnSe nanocrystals but also gives insights into the shape and phase control of other colloidal nanocrystals.

Fluorescence intensity ratio-based temperature sensing with a self-referencing characteristic is highly demanded for reliable and accurate sensing. Although enormous efforts have been devoted to explore high-performance luminescent temperature probes, it remains a daunting challenge to achieve highly relative sensitivity which determines temperature resolution. Herein, we employ a novel strategy to achieve temperature probes with ultrahigh relative sensitivity through integrating both positive and negative thermal quenching effect into a hydrogel. Specifically, Er3+ ions show evidently a positive thermal quenching effect in Yb/Er:NaYF4@NaYF4 nanocrystals while Nd3+ and Tm3+ ions in a Yb2W3O12 bulk exhibit prominently a negative thermal quenching effect. With elevating temperature from 313 to 553 K, the fluorescence intensity ratio of Er (540 nm) to Nd (799 nm) and Tm (796 nm) to Er (540 nm) is significantly decreased about 1654 times and increased about 14,422 times, respectively. The maximum relative sensitivity of 15.3% K-1 at 553 K and 23.84% K-1 at 380 K are achieved. The strategy developed in this work sheds light on highly sensitive probes using lanthanide ion-doped materials.

Nanorod-like CoP nanoparticles were fabricated from different precursors of Co(OH)