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The biggest challenge is to develop a low cost and readily available catalyst to replace expensive commercial Pt/C for efficient electrochemical oxygen reduction reaction (ORR). In this research, closo-[B12H12]2− and 1,10-phenanthroline-iron complexes were introduced into the porous metal-organic framework by impregnation method, and further annealing treatment achieved the successful anchoring of single-atom-Fe in B-doped CN Matrix (FeN4CB). The ORR activity of FeN4CB is comparable to the widely used commercial 20 wt% Pt/C. Where the half-wave potential (E1/2) in alkaline medium up to 0.84 V, and even in the face of challenging ORR in acidic medium, the E1/2 of ORR driven by FeN4CB is still as high as 0.81 V. When FeN4CB was used as air cathode, the open circuit voltage of Zn-air battery reaches 1.435 V, and the power density and specific capacity are as high as 177 mW cm−2 and 800 mAh gZn−1 (theoretical value: 820 mAh gZn−1), respectively. The dazzling point of FeN4CB also appears in the high ORR stability, whether in alkaline or acidic media, E1/2 and limiting current density are still close to the initial value after 5000 times cycles. After continuously running the charge-discharge test for 220 h, the charge voltage and discharge voltage of the rechargeable zinc-air battery with FeN4CB as the air cathode maintained the initial state. Density functional theory calculations reveals that introducing B atom to Fe–N4–C can adjust the electronic structure to easily break O = O bond and significantly reduce the energy barrier of the rate-determining step resulting in an improved ORR activity.

In this study, a new hollow nanotube material, 30% Co–CHNTs was prepared by the impregnation–chemical reduction–calcination method. This material can be used as a peroxymonosulfate (PMS) activator to catalyse the degradation of sulfamethoxazole (SMX). The best reaction conditions that correspond to the degradation rate of SMX, up to 97.5%, are as follows: the concentration of SMX is 10 mg L−1, the amount of catalyst is 0.20 g L−1, the dosage is 1.625 mM, and the solution pH is 6.00. X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma optical emission spectrometry (ICP-OES) show that the calcined composites mainly stimulate an increase in the content of bivalent cobalt in PMS and reduce the leaching of cobalt ions after the reaction. Additionally, the 30% Co–CHNTs + PMS reaction system exhibits a reasonable SMX degradation rate in a natural organic matter solution and excellent stability after three repeated experiments. Furthermore, the possible degradation mechanism in the 30% Co–CHNTs + PMS reaction system was analysed through electron paramagnetic resonance (EPR) and free-radical capture experiments, and it was observed that the non-radical degradation of 1O2 plays a leading role in SMX degradation. Finally, according to the nine degradation intermediates detected by liquid chromatography-mass spectrometry (LC–MS), four possible SMX degradation routes were proposed. This study proved that a 30% Co–CHNTs heterogeneous catalyst is easily prepared, inexpensive, and environmentally friendly and has potential application in antibiotic wastewater treatment.

Developing sensing platforms that simultaneously integrate high sensitivity and accuracy has been a promising but challenging task for the detection of protein biomarkers in clinical samples. Herein, we engineered an Au nanostar-based liquid phase interfacial ratiometric SERS platform with programmable entropy-driven DNA circuits to detect the protein biomarker Mucin 1 (MUC1) in clinical samples.

Dynamic degradation becomes a critical issue for thin-film transistors (TFTs) used in emerging new displays driven by high frequency gate voltage ${V}_{\text {G}}$ pulses. In this study, ${V}_{\text {G}}$ pulse rising edge dependent dynamic hot carrier degradation of poly-Si TFTs is investigated. It is demonstrated that rising edge of ${V}_{\text {G}}$ pulses which swing within the OFF-state of TFTs causes the degradation, while that of normal ${V}_{\text {G}}$ pulses which switch between the ON and OFF states across the flat band voltage ${V}_{\text {FB}}$ of TFTs does not. Based on transient TCAD simulation, the underlying mechanism of rising edge dependent degradation is proposed, which is based on the non-equilibrium PN junction degradation model previously proposed to explain ${V}_{\text {G}}$ pulse falling edge dependent degradation of poly-Si TFTs. Hence, the dynamic degradation model of poly-Si TFTs related to both rising and falling edge of the ${V}_{\text {G}}$ pulses can be unified now, which is applicable to fast gate pulses with steep rising and/or falling edges in sub- $\mu \text{s}$ level.

Degradation of flexible low-temperature poly-Si TFTs under dynamic bending stress is studied in controlled ambient of different kinds. It is demonstrated that synergistic effect of H2O vapor and O2 is the origin of the positive threshold voltage ( ${V}_{\text {th}}$ ) degradation of poly-Si TFTs under dynamic bending stress in the air ambient, while the dynamic bending stress alone does not cause any TFT degradation. The degradation is found to strongly depend on the ratio of O2 to H2O vapor in the ambient. A degradation model of “H2O and O2 assisted electron transport and capture” is proposed, which is based on the participation of both reactants in reactions with dangling bonds along the micro-/nano- cracks penetrating through the passivation layer into the active region of TFTs, formed under the dynamic bending stress.

Degradation and failure behaviors of the flexible low-temperature poly-Si (LTPS) thin film transistors (TFTs) under repetitive stretch stress parallel to channel length ( ${L}$ ) direction are investigated. A geometric effect is observed in degradation of the threshold voltage ( $\Delta {V}_{\text {TH}}$ ), which depends on the channel width ( ${W}$ ) and active area ( $\textit {WL}$ ), while has a weak correlation with ${L}$ . Three failure modes of TFTs are identified from their ${I}$ – ${V}$ characteristics: damage in the gate insulator (GI), channel traps generation, and metal line cracks. Failure statistics show that the GI failure has a low failure rate and follows the exponential distribution, while the other two modes have high failure rates in the early stage of the stretch cycles, and their failure distributions follow the limited failure population (LFP) model.

The degradation mechanism of amorphous InGaZnO (a-IGZO) thin-film transistors (TFTs) under pulse drain bias stress is investigated. Although the degradation mechanism is found to be a dc one, the shift of the transfer curve under the pulse drain bias (0–20 V) is unexpectedly larger than that under dc drain bias (20 V) within the same equivalent stress time. The degradation mechanism is proposed to be tunneling and trapping of electrons in the etching stop layer during the pulse peak time and that in the gate dielectric during the pulse base time under the extended drain electrode region of the a-IGZO TFT, where the occurrence of the latter is triggered by the former. A solution for enhancing the stability of the a-IGZO TFT is also suggested.

Roles of gate voltage ( ${V}_{G}$ ) and stress power in self-heating (SH) degradation of amorphous InGaZnO thin-film transistors have been clarified. Normally observed positive threshold voltage ( ${V}_{th}$ ) shift is attributed to the electron trapping mechanism, which is enhanced by both the effective ${V}_{G}$ and stress power. The effective ${V}_{G}$ plays a dominant role in most cases, while stress power takes control only if it is high enough. Following the positive ${V}_{th}$ shift, a second-stage negative ${V}_{th}$ backshift is also observed and is attributed to the water-related positive charges generation mechanism. It is enhanced by both stress power and effective ${V}_{G}$ for which stress power is found to be the dominant factor.

Degradations of elevated-metal metal oxide (EMMO) thin-film transistors (TFTs) under positive bias stress (PBS) and positive bias illumination stress (PBIS) are systematically investigated and compared. An intrinsic correlation between PBS and PBIS degradation is demonstrated. Continuous negative threshold voltage ( ${V}_{\text {th}}$ ) shift is observed under both stresses, with similar time-dependent $V_{\text {th}}$ shift and recovery behavior. Characterization parameters for dependencies of ${V}_{\text {th}}$ shift on both stress ${V}_{G}$ and temperature are also very close for the two degradations. PBS and PBIS degradation of EMMO TFTs and their correlation can be consistently understood based on a unified model, which emphasizes stress-induced accumulation of doubly-ionized ${V}_{O}$ traps at the back-channel interface, and is verified with simulation.

Localized scleroderma is a rare soft tissue disorder characterized by a thickening of the skin from excessive collagen deposits. For patients with face involved, soft tissue depression and atrophy could cause serious facial contour deformity and adversely affect the patients' quality of social life. However, localized scleroderma cases with delicate facial aesthetic subunits defects were rarely reported to be surgically reconstructed. In this study, we present 2 patients with nasal subunits and oral subunit deformities caused by localized scleroderma respectively. The first patient with a right-side alar defect and nasal dorsum depression, forehead depression and eyebrow depression were treated through a 2-stage surgical approach, with microvascular preauricular and helical rim flap and dermofat graft transplantation. The lower lip and mandible defects of the second patient were reconstructed with a combination of submental flap and fat grafting. The transplanted dermofat graft, fat graft, the microvascular free flap, and the submental flap survived completely and maintained adequate tissue volume and facial contour during the follow-up time of 2 years. Both patients were satisfied with the overall aesthetic results. This clinical report supports the use of microsurgical flap and tissue grafts on the treatment of localized scleroderma (LS) caused facial aesthetic subunits deformities.

Different from the conventional degradation phenomenon under positive bias stress (PBS), the shift of the transfer characteristic curve of polycrystalline silicon thin-film transistors (TFTs) to the negative gate bias direction after PBS is observed and reported. The PBS degradation is found to be recoverable and the recovery proceeds at a faster rate first and then continues at a much slower rate. The recovery can be further accelerated at a higher temperature or by applying a negative gate bias. After detailed data analysis, the degradation mechanism is proposed to be the generation of protons in the gate oxide and its accumulation at the channel/gate oxide interface. The proposed degradation model could explain both the degradation phenomena and the recovery behaviors of PBS degradation.

In the electrochemiluminescence (ECL) field, most reported luminophores were focused on high-triggering potential and short wavelength, which was adverse for the ECL theory study and application at low potentials. Perylene diimide derivatives could emit near-infrared (NIR) ECL at low-triggering potential; however, they are always highly aggregated into a microrod structure and stacked together, which largely limited their application in biological fields such as bio-sensing and bio-imaging. To overcome these obstacles, we designed a novel perylene diimide molecule, namely N,N′-dicaproate sodium-3,4,9,10-perylenedicarboximide (PDI-COONa). This molecule self-assembled into a two-dimensional network nanostructure, which largely decreased the aggregation degree of PDI molecules and provided solid bases for designing lowly-aggregated PDI molecules. Also, the formed nanoluminophore produced strong emission at −0.26 V with an NIR wavelength 700 nm, which should be due to the excited J-type PDI-COO− dimers. Moreover, this network nanoluminophore well-dispersed on graphene oxide (GO) as an ECL nanomaterial to label secondary antibodies and fabricate a sandwiched immunosensor for alpha-fetoprotein (AFP) detection between 0 and −0.6 V. This immunosensor showed a wider linear response for AFP ranging from 0.1 fg mL−1 to 1 μg mL−1 with a low detection limit 0.0353 fg mL−1 compared with other immunosensors based on PDI microrod-modified GO ECL materials. The fabricated immunosensor also showed good feasibility in human serum samples.

A unique ratiometric MALDI-MS strategy is proposed for the convenient and reliable quantitation of alkaline phosphatase based on the homogeneous enzymatic cleavage of a coded phosphopeptide (CPP)-triggered double-signal output. The dynamic range can be tuned by simply adjusting the primary concentration of CPP. The proposed strategy is also capable of being challenged by real human serum, and thus it may offer a wonderful approach for the convenient identification and quantitation of various enzyme activities in clinical diagnosis.

A novel ratiometric electrochemical biosensing strategy based on T7 exonuclease (T7 Exo)-assisted homogenous target recycling coupling hairpin assembly triggered dual-signal output was proposed for the accurate and sensitive detection of microRNA-141 (miRNA-141). Concretely, in the presence of target miRNA, abundant signal transduction probes were released via the T7 Exo-assisted homogenous target recycling amplification, which could be captured by the specially designed ferrocene-labeled hairpin probe (Fc-H1) on -electrode interface and triggered the nonenzymatic catalytic hairpin assembly (Fc-H1 + MB-H2) to realize the cascade signal amplification and dual-signal output. Through such a conformational change process, the electrochemical signal of Fc (IFc) and MB (IMB) is proportionally and substantially decreased and increased. Therefore, the signal ratio of IMB/IFc can be employed to accurately reflect the true level of original miRNA. Benefiting from the efficient integration of the T7 Exo-assisted target recycle, nonenzymatic hairpin assembly and dual-signal output mode, the proposed sensor could realize the amplified detection of miRNA-141 effectively with a wide detection range from 1 fM to 100 pM, and a detection limit of 200 aM. Furthermore, it exhibits outstanding sequence specificity to discriminate mismatched RNA, acceptable reproducibility and feasibility for real sample. This strategy effectively integrated the advantages of multiple amplification and ratiometric output modes, which could provide an accurate and efficient method in biosensing and clinical diagnosis.

Herein, single-atom niobium-doped boron–carbon–nitrogen nanotubes (SANb-BCN) were synthesized and utilized to fabricate an electrochemical sensor for the detection of nitrobenzene (NB), an environmental pollutant. SANb-BCN were characterized through scanning transmission electron microscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction analysis, and Raman spectroscopy. The Nb-BNC material modified on a glassy carbon electrode (GCE) showed an excellent electrochemical response behavior toward NB. The SANb-BCN-modified GCE (SANb-BCN/GCE) gave rise to a prominent NB reduction peak at −0.6 V, which was positively shifted by 120 mV from the NB reduction peak of the bare GCE. Furthermore, the NB peak current (55.74 μA) obtained using SANb-BCN/GCE was nearly 42-fold higher than that using the bare GCE (1.32 μA), indicating that SANb-BCN/GCE is a highly sensitive electrochemical sensor for NB. An ultralow limit of detection (0.70 μM, S/N = 3) was also achieved. Furthermore, the SANb-BCN/GCE sensor was found to possess favorable anti-interference ability during NB detection; thus, the presence of various organic and inorganic coexisting species, including Mg2+, Cr6+, Cu2+, K+, Ca2+, NH4+, Cd2+, urea, 1-bromo-4-nitrobenzene, 3-hydroxybenzoic, terephthalic acid, 1-iodo-4-nitrobenzene, and toluene, minimally affected the NB detection signal. Notably, the SANb-BNC sensor material exhibited high sensitivity and specificity toward detection of NB in environmental samples. Thus, the use of the proposed sensor will serve as an effective alternative method for the identification and treatment of pollutants.

Most biosensors for folate receptor (FR) detection based on folic acid (FA) recognition usually contain FA-linked single-strand DNA (FA-ssDNA) and nuclease to promote sensitivity, which increases expenses and involves complicated assay processes. A few electrochemiluminescence (ECL) sensors that do not use FA-ssDNA and nuclease directly graft FA onto an ECL nanomaterial through covalent bonding for FR detection. In this study, we used FA-ssDNA to non-covalently graft FA onto π-conjugated ECL nanomaterial graphene oxide (GO)/perylene–aniline for fabricating ultrasensitive FR sensors without nuclease. 3,4,9,10-Perylenetetracarboxylic dianhydride (PTCDA) and aniline (An) self-assembled into π-conjugated nanorods, which were then loaded onto GO. This material was reported to produce 673 nm-dominated ECL with the co-reactant K2S2O8, and was used as an ECL platform. FA-modified Poly-dA-ssDNA (FA-Poly-dA-ssDNA) molecules, consisting of 20 bases, were attached to the surface of GO/PTCDA-An to capture FR. A significant decrease of ECL intensity was observed due to the steric hindrance of FR. The proposed sensors exhibited high detection sensitivity with a linear range from 1 fg mL−1 to 1 ng mL−1 and a detection limit of 0.636 fg mL−1. The sensors also showed good potential in real sample detection. Without introducing nuclease and complicated chemical reactions, this work provides a new sensing strategy for protein detection based on molecular recognition, which is extremely important in clinical diagnosis.

The latissimus dorsi muscle (LDM) flap has been widely accepted as the best choice for subtotal or total scalp reconstruction. Because of the unique anatomic and functional features of scalp, ulcerations formation would occur after reconstructive surgeries. in this study, we are presenting a patient with a large scalp defect successfully reconstructed by a latissimus dorsi muscle free flap. Ulcerations with skull exposure formed on the transplanted flap after the first surgery. They were subsequently repaired by flap recycling and tissue expansion techniques. An excellent reconstructive outcome was achieved at the 30-month follow-up after the last surgery and no further complication was found. This clinical report highlights the possibility of ulcer formation after scalp reconstructive surgeries and supports the use of recycle flaps and tissue expanders to manage postoperative ulcerations after latissimus dorsi muscle free flap transplantation.

High-voltage (≥1000 V) electrical injury is always related to high mortality and poor prognosis. The incidence rates of the high-voltage electrical injuries of the neck are lower than those of the other parts of the body. This article reports a case of the reconstruction of severe neck scar contracture after electrical injury. Compared with cases of scar contractures caused by nonelectrical injuries, this case had the following remarkable characteristics: extremely severe difficult airway, contracture scars involving whole layers of tissue, muscle and nerve damage, mandibular retraction, and poor occlusal relationship. The chief complaints of the patient upon admission, including forced position and continuous salivation, were greatly relieved through several operations by using different kinds of flaps and offering support to the flap from the palmar tendon and relocated mandible. However, the problem of salivation was incompletely solved. This problem might be caused by damage to related nerves and masticatory muscle function caused by high-voltage electrical injury. The patient was satisfied with the recovery of his appearance and movement function.

In electrochemiluminescence (ECL) field, screening luminophores, especially potential-resolved luminophores with the same parent chromophore, is essential for the development of fundamental theory ...

Characteristics of amorphous indium–gallium–zinc oxide (a-IGZO) thin-film transistors (TFTs) are highly dependent on the hydrogen (H) content within the device architecture, for example in the etch-stop layer (ESL) of the elevated-metal metal-oxide (EMMO) TFTs. The serious apparent “short-channel effect (SCE)” was caused by the H diffusion from source/drain (S/D) to channel. Such SCE deterioration can be suppressed by thermal dehydrogenation at a cost of long annealing time, especially for a transistor architecture with a-IGZO S/D covered with H-rich silicon nitride (SiN x :H) and further capped with metallic H-diffusion barrier. The dehydrogenation efficiency is found to be significantly enhanced by fluorinating the a-IGZO. By optimizing the device architecture and/or the fluorination process to enhance the dehydrogenation, the SCE can be efficiently eliminated with well-maintained performance even for ${2}~\mu \text{m}$ -long a-IGZO TFTs.

A physical-based analytical kink current model for polycrystalline -silicon (poly-Si) thin-film transistors (TFTs) has been proposed. Two important mechanisms for the kink current, namely carrier impact ionization and the parasitic bipolar junction transistor effect, are physically included in the model without introducing any artificial parameters. The proposed kink current model is fully compatible with existing ON-state drain current models of poly-Si TFTs. Model parameter extraction procedure is presented, which is based on a group of output characteristics of poly-Si TFTs with different channel lengths. The model prediction straightforwardly calculated with a set of extracted parameters is verified by excellent agreement with experimental output characteristics measured from TFTs over a range of channel lengths and gate voltages.

Quantitative analysis of receptor protein expression is essential to give new insights into tumor-related research. Benefitting from their high sensitivity and low background, photoelectrochemical ...

Dynamic hot-carrier (HC) degradation can be effectively suppressed in four-terminal low-temperature poly-Si (LTPS) thin film transistors (TFTs) with a carrier injection terminal. In order to enhance the reliability of the four-terminal LTPS TFTs, geometry effect of the carrier injection terminal, such as width and location, on the dynamic HC degradation is systematically studied. It shows that a wider carrier injection terminal, which provides more carriers injection, can suppress the degradation more effectively. As for the location, if the injection terminal is adjacent to the edge of the drain depletion region, which extends into the channel at the falling time of the gate voltage pulses, the four-terminal TFTs can provide the best immunity to the dynamic HC degradation. The proposed optimization scheme can greatly enhance the reliability of LTPS TFTs, and the mechanism can be understood based on the nonequilibrium p-n junction degradation model.

The synthesis of hierarchical nanosized zeolite materials without growth modifiers and mesoporogens remains a substantial challenge. Herein, we report a general synthetic approach to produce hierarchical nanosized single-crystal aluminophosphate molecular sieves by preparing highly homogeneous and concentrated precursors and heating at elevated temperatures. Accordingly, aluminophosphate zeotypes of LTA (8-rings), AEL (10-rings), AFI (12-rings), and -CLO (20-rings) topologies, ranging from small to extra-large pores, were synthesized. These materials show exceptional properties, including small crystallites (30-150 nm), good monodispersity, abundant mesopores, and excellent thermal stability. A time-dependent study revealed a non-classical crystallization pathway by particle attachment. This work opens a new avenue for the development of hierarchical nanosized zeolite materials and understanding their crystallization mechanism.

A DNA immobilization-free ECL aptasensor was developed for the detection of 8-hydroxy-2'-deoxygunosine based on the diffusion mediated ECL quenching effect. This ECL aptasensor exhibited a high sensitivity and low detection limit by combining homogeneous DNA reaction with dual signal amplifications: target-induced multi-DNA release and Exo I-assisted target recycling.

Most electrochemiluminescence (ECL) studies focus on the single emission of luminophores, which severely limits the development of the multi-color ECL fundamental theory and applications. Herein, we prepared a multi-color ECL supramolecular nanomaterial self-assembled by 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) and aniline (An) through hydrogen bonding. This PTCDA-An supramolecular nanomaterial simultaneously produced multi-color emissions peaking at 486, 692 and 760 nm with K2S2O8 as a coreactant. These multi-color emissions were assigned to the excited PTCDA monomer (486 nm), H-dimer (692 nm) and J-dimer (760 nm). The simultaneously increased dual-color ECL intensity significantly enhanced the total ECL intensity of PTCDA-An. Furthermore, this highly efficient ECL nanomaterial was used as an ECL platform to construct a label-free immunosensor for tumor marker carcinoembryonic antigen (CEA) detection. The total ECL intensity of the immunosensor sensitively decreased due to the simultaneously decreased ECL of multiple emissions. Also, this immunosensor exhibited a wide linear range from 1 pg mL-1 to 10 μg mL-1 with a low detection limit of 0.23 pg mL-1. The multi-color ECL from the same luminophore PTCDA in this work also provides a new perspective for multi-color ECL biomaterial design.

In this work, a method for quantifying the activity of formamidopyrimidine DNA glucosylase (Fpg) was designed based on phosphate group (P)-modulated multi-enzyme catalysis and fluorescent copper nanoclusters (CuNCs). By eliminating 8-oxoguanine from double-stranded DNA, Fpg generates a nick with P at both 3' and 5' termini. Subsequently, part of the DNA is digested by 5'P-activated lambda exonuclease (λ Exo), and the generated 3'P disables exonuclease I (Exo I), resulting in the generation of single-stranded DNA containing poly(thymine) (poly(T)). Using poly(T) as templates, CuNCs were prepared to emit intense fluorescence as the readout of this method. However, in the absence of Fpg, the originally modified 5'P triggers the digestion of λ Exo. In this case, fluorescence emission is not obtained because CuNCs cannot be formed without DNA templates. Therefore, the catalysis of λ Exo and Exo I can be tuned by 5'P and 3'P, which can be further used to determine the activity of Fpg. The fluorescent Fpg biosensor works in a "signal-on" manner with the feature of "zero" background noise, and thus shows desirable analytical features and good performance. Besides, Fpg in serum samples and cell lysate could be accurately detected with the biosensor, indicating the great value of the proposed system in practical and clinical analysis.

Perylene diimide derivatives (PDIs) are suitable ECL luminophore candidates with low triggering potentials and strong ECL signals for fundamental studies and practical applications. However, PDIs tend to aggregate, which affects their optical properties and limits their application in bio-imaging and bio-sensing fields. In this study, an ECL sensor is fabricated based on the layer-by-layer (LBL) assembly of N, N-bis(phosphonomethyl)-3,4,9,10-perylene diimide (PMPDI) and Zr

Electrochemical nitrate reduction reaction (NIRR) driven by sustainable energy is not only expected to realize the green production of ammonia under ambient conditions, but also a promising way to purify nitrate wastewater. The ammonia yield rate and Faradaic efficiency of NIRR catalyzed by Pd10Cu/BCN constructed with structural constraints and pre-embedded reducing agent strategies were as high as 102,153 μg h