Organic–inorganic hybrid perovskites have attracted considerable attention due to their superior optoelectronic properties. Traditional one‐step solution‐processed perovskites often suffer from ...defects‐induced nonradiative recombination, which significantly hinders the improvement of device performance. Herein, treatment with green antisolvents for achieving high‐quality perovskite films is reported. Compared to defects‐filled ones, perovskite films by antisolvent treatment using methylamine bromide (MABr) in ethanol (MABr‐Eth) not only enhances the resultant perovskite crystallinity with large grain size, but also passivates the surface defects. In this case, the engineering of MABr‐Eth‐treated perovskites suppressing defects‐induced nonradiative recombination in perovskite solar cells (PSCs) is demonstrated. As a result, the fabricated inverted planar heterojunction device of ITO/PTAA/Cs0.15FA0.85PbI3/PC61BM/Phen‐NADPO/Ag exhibits the best power conversion efficiency of 21.53%. Furthermore, the corresponding PSCs possess a better storage and light‐soaking stability.
Antisolvent engineering is employed to tune the crystal nucleation and grain growth of perovskite for achieving efficient perovskite solar cells. The engineering of perovskites treated with the green antisolvent MABr‐Eth, suppressing defects‐induced nonradiative recombination in perovskite solar cells, is developed. As expected, the device delivers over 21% power conversion efficiency and a better storage and light‐soaking stability.
Catalytic alkene difunctionalization via Si−H and C−H activations represents an ideal atom‐ and step‐economic pathway for quick assembly of molecular complexity. We herein developed a ...visible‐light‐promoted metal‐free difunctionalization of alkenes using abundant CO2 and readily available Si−H and C(sp3)−H bonds as feedstocks. Through the merger of photoredox and hydrogen‐atom‐transfer catalysis, a variety of value‐added compounds, such as β‐silacarboxylic acids and acids bearing a γ‐heteroatom (e.g., N, O, S) could be directly accessed from simple alkenes in a redox‐neutral fashion.
Photocarboxylation: Visible‐light‐promoted metal‐free difunctionalization of alkenes using CO2 and readily available Si−H and C(sp3)−H reagents has been realized by the merging of photoredox and hydrogen‐atom‐transfer catalysis. A variety of valuable compounds, such as β‐silacarboxylic acids and acids bearing a γ‐heteroatom (e.g., N, O, S) can be directly accessed from simple alkenes in a redox‐neutral fashion.
Reactive oxygen species (ROS) depletion and low ROS production that result from the intratumoral redox metabolism equilibrium and low energy conversion efficiency from ultrasound mechanical energy to ...ROS‐represented chemical energy, respectively, are two vital inhibitory factors of sonodynamic therapy (SDT). To address the two concerns, a tumor metabolism‐engineered composite nanoplatform capable of intervening intratumoral ROS metabolism, breaking the redox equilibrium, and reshaping the tumor microenvironment is constructed to reinforce SDT against tumors. In this metabolism‐engineered nanoplatform, Nb2C nanosheets serve as the scaffold to accommodate TiO2 sonosensitizers and l‐buthionine‐sulfoximine. Systematic experiments show that such nanoplatforms can reduce ROS depletion via suppressing glutathione synthesis and simultaneously improving ROS production via the Nb2C‐enhanced production and separation of electron–hole pairs. Contributed by the combined effect, net ROS content can be significantly elevated, which results in the highly efficient anti‐tumor outcomes in vivo and in vitro. Moreover, the combined design principles, that is, tumor metabolism modulation for reducing ROS depletion and electron–hole pair separation for facilitating ROS production, can be extended to other ROS‐dependent therapeutic systems.
An intratumoral metabolism modulation‐engineered sonodynamic therapy (SDT)‐based nanoplatform has been constructed to break the reactive oxygen species (ROS)‐involved redox metabolism equilibrium and reshape the tumor microenvironment for reducing ROS depletion, and simultaneously facilitate ROS production via enhancing the production and separation of electron–hole pairs, which enables the significantly improved net content of ROS for highly‐efficient SDT against tumors.
China is one of the countries with the highest incidence of gastric cancer. There are differences in epidemiological characteristics, clinicopathological features, tumor biological characteristics, ...treatment patterns, and drug selection between gastric cancer patients from the Eastern and Western countries. Non‐Chinese guidelines cannot specifically reflect the diagnosis and treatment characteristics for the Chinese gastric cancer patients. The Chinese Society of Clinical Oncology (CSCO) arranged for a panel of senior experts specializing in all sub‐specialties of gastric cancer to compile, discuss, and revise the guidelines on the diagnosis and treatment of gastric cancer based on the findings of evidence‐based medicine in China and abroad. By referring to the opinions of industry experts, taking into account of regional differences, giving full consideration to the accessibility of diagnosis and treatment resources, these experts have conducted experts’ consensus judgement on relevant evidence and made various grades of recommendations for the clinical diagnosis and treatment of gastric cancer to reflect the value of cancer treatment and meeting health economic indexes. This guideline uses tables and is complemented by explanatory and descriptive notes covering the diagnosis, comprehensive treatment, and follow‐up visits for gastric cancer.
At the frontier of electrocatalysis and heterogeneous reactions, significant effort has been devoted to Pt‐based nanomaterials owing to their advantages of tunable morphology and excellent catalytic ...properties. In contrast to Pt‐based nanocatalysts with other morphologies, nanowire catalysts, especially 1D ultrafine nanowire (NW) structure, are garnering increased attention because of their advantages of high atomic efficiency, intrinsic isotropy, rich high‐index facets, better conductivity, robust structure stability for prohibiting dissolution, ripening, and aggregation. Regardless of these advantages, it is still challenging to realize the precise control of ultrafine Pt‐based NWs in terms of their size, crystal phase structure, and composition. Aiming to synthesize advanced ultrafine Pt‐based NWs catalysts with higher activity, durability, and selectivity toward catalytic reactions, this review summarizes the recently available approaches for improving the catalytic performance of ultrafine Pt‐based NWs with detailed guidance. A summary of recent progress in ultrafine Pt‐based NWs catalysts for advanced catalysis and heterogeneous reactions is also provided. Furthermore, integrated experimental and theoretical studies are reviewed to explain the activity, stability, and selectivity enhancement mechanism. In the final section, the challenges and outlook are also discussed to provide guidance for the rational engineering of efficient ultrafine Pt‐based NWs catalysts for applications in renewable‐energy‐related devices.
Recent progress in advanced catalysis promoted by ultrafine platinum‐based nanowires is summarized with focus on geometric and electronic structure engineering including strain, facet, synergistic role, and electronic property engineering. Existing challenges and future development directions to obtain more credible Pt‐based electrocatalysts are highlighted.
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•Overview the surface and interface engineering of catalysts for electrocatalysis.•Discuss the interfacial effect of catalysts for overall water splitting.•Outline the detail ...mechanism of HER, OER, and OWS on surface of catalysts.•Show perspective of interface engineering of catalyst for future electrocatalysis.
Developing highly efficient overall water splitting (OWS) electrocatalysts based on noble-metal-free materials to produce fuel is stimulated by increasing concerns regarding global energy security and environment contamination. Tremendous accomplishments in the design and fabrication of non-noble metal counterpart to substitute the noble metal catalysts for efficient oxygen evolution reaction (OER), hydrogen evolution reaction (HER), and OWS are boosting the development of clean hydrogen fuel production. Recent researches and advances reveal that the surface and interface atomic engineering can readily induce novel physiochemical properties, such as more surface active sites, electronic effect, and strong synergistic effect, offering new and efficient avenues toward largely promoted electrocatalytic performance. In this review, we focus on the recent progress in designing and constructing high-performance non-noble metal catalysts for efficient OER, HER, and OWS through surface and interface engineering. A few of surface and interface effects have been highlighted to account for the influence of electrocatalytic properties observed in catalysts. And a series of the surface and interface engineering strategies have been utilized in non-noble metal counterparts design, including traditional chemical method (e.g. wet-chemical, hydrothermal/annealing), deposition (chemical/electrochemical deposition), and in-situ electrochemical oxidation strategy. The rational design of noble-metal-free counterparts with excellent electrocatalytic performance based on surface and interface engineering could realize improved electrocatalysis, offering a deep understanding of structure–activity relationships.
Since the discovery of NMDA receptor (NMDAR) dependent long-term potentiation (LTP) in the hippocampus, many studies have demonstrated that NMDAR dependent LTP exists throughout central synapses, ...including those involved in sensory transmission and perception. NMDAR LTP has been reported in spinal cord dorsal horn synapses, anterior cingulate cortex and insular cortex. Behavioral, genetic and pharmacological studies show that inhibiting or reducing NMDAR LTP produced analgesic effects in animal models of chronic pain. Investigation of signalling mechanisms for NMDAR LTP may provide novel targets for future treatment of chronic pain.
Controlling the self‐assembly morphology of π‐conjugated block copolymer is of great interesting. Herein, amphiphilic poly(3‐hexylthiophene)‐block‐poly(phenyl isocyanide)s (P3HT‐b‐PPI) copolymers ...composed of π‐conjugated P3HT and optically active helical PPI segments were readily prepared. Taking advantage of the crystallizable nature of P3HT and the chirality of the helical PPI segment, crystallization‐driven asymmetric self‐assembly (CDASA) of the block copolymers lead to the formation of single‐handed helical nanofibers with controlled length, narrow dispersity, and well‐defined helicity. During the self‐assembly process, the chirality of helical PPI was transferred to the supramolecular assemblies, giving the helical assemblies large optical activity. The single‐handed helical assemblies of the block copolymers exhibited interesting white‐light emission and circularly polarized luminescence (CPL). The handedness and dissymmetric factor of the induced CPL can be finely tuned through the variation on the helicity and length of the helical nanofibers.
One hand makes light work: The crystallization‐driven asymmetric self‐assembly (CDASA) of the block copolymers leads to the formation of single‐handed helical nanofibers with controlled length, narrow dispersity, and well‐defined helicity. The helical assembly of the block copolymer induced white‐light emission and intense circularly polarized luminescence (CPL).
Metal–nitrogen–carbon (M–N–C) materials have attracted much interest in bifunctional oxygen‐involving electrocatalysis for rechargeable Zn–air batteries. Such M–N–C electrocatalysts with M–Nx sites ...show good activity for the oxygen reduction reaction (ORR) but moderate activity for the oxygen evolution reaction (OER). Herein, an oxygen‐rich M–N–C material (O–Co–N/C) with a highly porous nanosheet structure is reported as a bifunctional oxygen electrocatalyst, which is prepared by the direct pyrolysis of ultrathin CoO nanosheets decorated with zeolitic imidazolate framework‐8 nanoparticles under an inert atmosphere. Particularly, Co nanoparticles in the O–Co–N/C electrocatalyst contain both Co–Nx and Co–Ox coordination environments to provide intrinsic active sites for the ORR and OER, respectively. Furthermore, electrochemical studies show that the O–Co–N/C catalyst retains comparable ORR activity to common M–N–C materials with a half‐wave potential of 0.85 V vs the reversible hydrogen electrode and better OER activity with an overpotential of 0.29 V at the current density of 10 mA cm−2. This study provides insights into the development of effective oxygen‐involving electrocatalysts with bifunctional metal active centers coordinated by both nitrogen and oxygen atoms.
In oxygen‐rich cobalt–nitrogen–carbon porous nanosheets, the Co–Nx and Co–Ox units consisting of cobalt centers coordinated with nitrogen and oxygen atoms act as the intrinsic oxygen reduction and oxygen evolution active sites, respectively, for bifunctional oxygen electrocatalysis and rechargeable Zn–air batteries.
Easily processed materials with the ability to transport excitons over length scales of more than 100 nanometers are highly desirable for a range of light-harvesting and optoelectronic devices. We ...describe the preparation of organic semiconducting nanofibers comprising a crystalline poly(di-
-hexylfluorene) core and a solvated, segmented corona consisting of polyethylene glycol in the center and polythiophene at the ends. These nanofibers exhibit exciton transfer from the core to the lower-energy polythiophene coronas in the end blocks, which occurs in the direction of the interchain π-π stacking with very long diffusion lengths (>200 nanometers) and a large diffusion coefficient (0.5 square centimeters per second). This is made possible by the uniform exciton energetic landscape created by the well-ordered, crystalline nanofiber core.
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