Jilin Normal University

This review focuses on the research progress of the efficient iodine capture in porous POP and MOF materials.

Main antioxidants in higher plants include glutathione, ascorbate, tocopherol, proline, betaine, and others, which are also information-rich redox buffers and important redox signaling components that interact with biomembrane-related compartments. As an evolutionary consequence of aerobic life for higher plants, reactive oxygen species (ROS) are formed by partial reduction of molecular oxygen. The above enzymatic and non-enzymatic antioxidants in higher plants can protect their cells from oxidative damage by scavenging ROS. In addition to crucial roles in defense system and as enzyme cofactors, antioxidants influence higher plant growth and development by modifying processes from mitosis and cell elongation to senescence and death. Most importantly, they provide essential information on cellular redox state, and regulate gene expression associated with biotic and abiotic stress responses to optimize defense and survival. An overview of the literature is presented in terms of main antioxidants and redox signaling in plant cells. Special attention is given to ROS and ROS-antioxidant interaction as a metabolic interface for different types of signals derived from metabolism and from the changing environment, which regulates the appropriate induction of acclimation processes or, execution of cell death programs, which are the two essential directions for higher plants.

Abstract Broadband near‐infrared (NIR) phosphor‐converted light emitting diode (pc‐LED) is demanded for wearable biosensing devices, but it suffers from low efficiency and low radiance. This study reports a broadband NIR Ca 3‐ x Lu x Hf 2 Al 2+ x Si 1− x O 12 :Cr 3+ garnet phosphor with emission intensity enhanced by 81.5 times. Chemical unit co‐substitution of [Lu 3+ −Al 3+ ] for [Ca 2+ −Si 4+ ] is responsible for the luminescence enhancement and further alters the crystal structure and electronic properties of the garnet. Using the optimized phosphor, a NIR pc‐LED with photoelectric efficiencies of 21.28%@10 mA, 15.75%@100 mA and NIR output powers of 46.09 mW@100 mA, 54.29 mW@130 mA is fabricated. The high power NIR light is observed to penetrate upper arms (≈8 cm). For application in NIR spectroscopy, the NIR pc‐LED is used as light source to measure transmission spectra of water, alcohol, and bovine hemoglobin solution. These results indicate the NIR garnet phosphor to be a promising candidate for NIR pc‐LED.

The acidic oxygen evolution reaction (OER) has long been the bottleneck of proton exchange membrane water electrolyzers given its harsh oxidative and corrosive environments. Herein, we suggest an effective strategy to greatly enhance both the acidic OER activity and stability of Co3O4 spinel by atomic Ru selective substitution on the octahedral Co sites. The resulting highly symmetrical octahedral Ru–O–Co collaborative coordination with strong electron coupling effect enables the direct dioxygen radical coupling OER pathway. Indeed, both experiments and theoretical calculations reveal a thermodynamically breakthrough heterogeneous diatomic oxygen mechanism. Additionally, the active Ru–O–Co units are well-maintained upon the acidic OER thanks to the electron transfer from surrounding electron-enriched tetrahedral Co atoms via bridging oxygen bonds that suppresses the overoxidation and thus dissolution of active Ru and Co species. Consequently, the prepared catalyst, even with a low Ru mass loading of ca. 42.8 μg cm–2, exhibits an attractive acidic OER performance with a low overpotential of 200 mV and a low potential decay rate of 0.45 mV h–1 at 10 mA cm–2. Our work suggests an effective strategy to significantly enhance both the acidic OER activity and stability of low-cost electrocatalysts.

A series of Mn2+-doped CsPbCl3 nanocrystals (NCs) was synthesized using reaction temperature and precursor concentration to tune Mn2+ concentrations up to 14%, and then studied using variable-temperature photoluminescence (PL) spectroscopy. All doped NCs show Mn2+ 4T1g → 6A1g d–d luminescence within the optical gap coexisting with excitonic luminescence at the NC absorption edge. Room-temperature Mn2+ PL quantum yields increase with increased doping, reaching ∼60% at ∼3 ± 1% Mn2+ before decreasing at higher concentrations. The low-doping regime is characterized by single-exponential PL decay with a concentration-independent lifetime of 1.8 ms, reflecting efficient luminescence of isolated Mn2+. At elevated doping, the decay is shorter, multiexponential, and concentration-dependent, reflecting the introduction of Mn2+–Mn2+ dimers and energy migration to traps. A large, anomalous decrease in Mn2+ PL intensity is observed with decreasing temperature, stemming from the strongly temperature-dependent exciton lifetime and slow exciton-to-Mn2+ energy transfer, which combine to give a strongly temperature-dependent branching ratio for Mn2+ sensitization.

The mechanism and conditions for the phase transformations from α-Fe2O3 to Fe3O4 and Fe3O4 to γ-Fe2O3 nanoparticles have been investigated by the thermal analysis method. The morphologies and structures of various nanoparticles after annealing in H2 : Ar at 294 °C and in an O2 atmosphere at 302 °C have been examined and characterized. Finally, we confirmed that the monodisperse, porous and magnetic γ-Fe2O3 nanoparticles could be obtained by annealing the α-Fe2O3 nanoparticles synthesized by the hydrothermal route.

Abstract The development of Li–S batteries is largely impeded by the growth of Li dendrites and polysulfide shuttling. To solve these two problems simultaneously, herein the study reports a “single atom array mimic” on ultrathin metal organic framework (MOF) nanosheet‐based bifunctional separator for achieving the highly safe and long life Li–S batteries. In the designed separator, the periodically arranged cobalt atoms coordinated with oxygen atoms (CoO 4 moieties) exposed on the surface of ultrathin MOF nanosheets, “single atom array mimic”, can greatly homogenize Li ion flux through the strong Li ion adsorption with O atoms at the interface between anode and separator, leading to stable Li striping/plating. Meantime, at the cathode side, the Co single atom array mimic serves as “traps” to suppress polysulfide shuttling by Lewis acid‐base interaction. As a result, the Li–S coin cells with the bifunctional separator exhibit a long cycle life with an ultralow capacity decay of 0.07% per cycle over 600 cycles. Even with a high sulfur loading of 7.8 mg cm −2 , an areal capacity of 5.0 mAh cm −2 can be remained after 200 cycles. Moreover, the assembled Li–S pouch cell displays stable cycling performance under various bending angles, demonstrating the potential for practical applications.

Photo-Fenton self-cleaning membranes have been developed by TA-Fe(<sc>iii</sc>) complex assembly, followed by the <italic>in situ</italic> mineralization of β-FeOOH for efficient oil/water emulsions separation.

A set of bulk ZnO samples implanted with O and Zn at various densities were investigated by photoluminescence. The implantation concentration of O and Zn is varied between 1×1017∕cm3 and 5×1019∕cm3. The samples were thermally treated in an oxygen gas environment after the implantation. The results clearly show the influence of O and Zn implantations on the deep-level emission. By comparing the photoluminescence spectra for the samples with different implantations, we can conclude that the VZn is responsible to the observed deep-level emission. In addition, a novel transition at the emission energy of 3.08eV at 77K appears in the O-implanted sample with 5×1019∕cm3 implantation concentration. The novel emission is tentatively identified as O-antisite OZn.

Capacitive deionization (CDI) is an emerging desalination technology for effective removal of ionic species from aqueous solutions. Compared to conventional CDI, which is based on carbon electrodes and struggles with high salinity streams due to a limited salt removal capacity by ion electrosorption and excessive co-ion expulsion, the emerging Faradaic electrodes provide unique opportunities to upgrade the CDI performance, i.e., achieving much higher salt removal capacities and energy-efficient desalination for high salinity streams, due to the Faradaic reaction for ion capture. This article presents a comprehensive overview on the current developments of Faradaic electrode materials for CDI. Here, the fundamentals of Faradaic electrode-based CDI are first introduced in detail, including novel CDI cell architectures, key CDI performance metrics, ion capture mechanisms, and the design principles of Faradaic electrode materials. Three main categories of Faradaic electrode materials are summarized and discussed regarding their crystal structure, physicochemical characteristics, and desalination performance. In particular, the ion capture mechanisms in Faradaic electrode materials are highlighted to obtain a better understanding of the CDI process. Moreover, novel tailored applications, including selective ion removal and contaminant removal, are specifically introduced. Finally, the remaining challenges and research directions are also outlined to provide guidelines for future research.

Electrochemical capacitor is the most promising energy storage device that can meet the demands of high power supply and long cycle life, however low energy density and high fabrication cost limit its further development. Researchers have paid more attention to the development of electrode material in the past, and very few people attach importance to the research of the electrolyte, especially the redox electrolyte, which is important for improving specific capacitance greatly. This paper presents a review of the research in not only electrode material but also redox aqueous electrolyte and together with an important part of supercapacitor device. The advantages and disadvantages for different electrode material and electrolyte are discussed. And the new trends in supercapacitor development are also summarized.

We report the correlated d0 ferromagnetism and photoluminescence in undoped single-crystalline ZnO nanowires synthesized by using a vapor transport method. We systematically tune the oxygen deficiency in the ZnO nanowires from 4% to 20% by adjusting the growth conditions, i.e., selecting different catalyst (Au or Ag) and varying the growth temperature. Our study suggests that oxygen vacancies induce characteristic photoluminescence and significantly boost the room-temperature ferromagnetism. Such undoped ZnO nanowires with tunable magnetic and optical properties are promising to find applications in multifunctional spintronic and photonic nanodevices.

High-efficiency blue CdSe/ZnS quantum dots (QDs) have been synthesized for display application with emission peak over 460 nm with the purpose of reducing the harmful effect of short-wavelength light to human eyes. To reach a better charge balance, different size ZnO nanoparticles (NPs) were synthesized and electrical properties of ZnO NPs were analyzed. Quantum dot light-emitting diodes (QLEDs) based on as-prepared blue QDs and optimized ZnO NPs have been successfully fabricated. Using small-size ZnO NPs, we have obtained a maximum current efficiency (CE) of 14.1 cd A–1 and a maximum external quantum efficiency (EQE) of 19.8% for QLEDs with an electroluminescence (EL) peak at 468 nm. To the best of our knowledge, this EQE is the highest value in comparison to the previous reports. The CIE 1931 color coordinates (0.136, 0.078) of this device are quite close to the standard (0.14, 0.08) of National Television System Committee (NTSC) 1953. The color saturation blue QLEDs show great promise for use in next-generation full-color displays.

Electrochemical CO2 reduction (CO2RR) using renewable energy sources represents a sustainable means of producing carbon-neutral fuels. Unfortunately, low energy efficiency, poor product selectivity, and rapid deactivation are among the most intractable challenges of CO2RR electrocatalysts. Here, we strategically propose a “two ships in a bottle” design for ternary Zn–Ag–O catalysts, where ZnO and Ag phases are twinned to constitute an individual ultrafine nanoparticle impregnated inside nanopores of an ultrahigh-surface-area carbon matrix. Bimetallic electron configurations are modulated by constructing a Zn–Ag–O interface, where the electron density reconfiguration arising from electron delocalization enhances the stabilization of the *COOH intermediate favorable for CO production, while promoting CO selectivity and suppressing HCOOH generation by altering the rate-limiting step toward a high thermodynamic barrier for forming HCOO*. Moreover, the pore-constriction mechanism restricts the bimetallic particles to nanosized dimensions with abundant Zn–Ag–O heterointerfaces and exposed active sites, meanwhile prohibiting detachment and agglomeration of nanoparticles during CO2RR for enhanced stability. The designed catalysts realize 60.9% energy efficiency and 94.1 ± 4.0% Faradaic efficiency toward CO, together with a remarkable stability over 6 days. Beyond providing a high-performance CO2RR electrocatalyst, this work presents a promising catalyst-design strategy for efficient energy conversion.

The photoluminescence stability of all-inorganic perovskite nanocrystals (CsPbBr₃) with different size is studied.

Abstract Efficient coupling solar energy conversion and N 2 fixation by photocatalysis has been shown promising potentials. However, the unsatisfied yield rate of NH 3 curbs its forward application. Defective typical perovskite, BaTiO 3 , shows remarkable activity under an applied magnetic field for photocatalytic N 2 fixation with an NH 3 yield rate exceeding 1.93 mg L −1 h −1 . Through steered surface spin states and oxygen vacancies, the electromagnetic synergistic effect between the internal electric field and an external magnetic field is stimulated. X‐ray absorption spectroscopy and density functional theory calculations reveal the regulation of electronic and magnetic properties through manipulation of oxygen vacancies and inducement of Lorentz force and spin selectivity effect. The electromagnetic effect suppresses the recombination of photoexcited carriers in semiconducting nanomaterials, which acts synergistically to promote N 2 adsorption and activation while facilitating fast charge separation under UV‐vis irradiation.

MXene, 2D transition metal carbides, nitrides, and carbonitrides with a unique 2D structure, inspired a series of function applications related to energy storage and conversion, biometrics and sensing, lighting, purification, and separation. Its surface terminations are confined by the adjacent MXene layers, and form the 2D planar space with symmetrical surfaces, which is similar to a 2D nanoreactor that can be utilized and determined MXene’s function. Based on the working principle, surface and interface play critical roles in the ion intercalation, physical/chemical adsorption, and chemical reaction process, and show significant effects on MXene’s properties and functions. Although there have been some reviews on MXene, less attention has been paid to the underlying principle of the involved surface chemistry, controllable design, and resultant properties. Herein, the regulation methods, characterization techniques, and the effects on properties of MXene surface terminations were summarized to understand the surface effects, and the relationship between the terminations and properties. We expected this review can offer the route for a series of ongoing studies to address the MXene surface environment and the guidelines for MXene’s application.

The seedlings of wheat were treated by salt-stress (SS, molar ratio of NaCl: Na2SO4 = 1: 1) and alkali-stress (AS, molar ratio of NaHCO3: Na2CO3 = 1: 1). Relative growth rate (RGR), leaf area, and water content decreased with increasing salinity, and the extents of the reduction under AS were greater than those under SS. The contents of photosynthetic pigments did not decrease under SS, but increased at low salinity. On the contrary, the contents of photosynthetic pigments decreased sharply under AS with increasing salinity. Under SS, the changes of net photosynthetic rate (P N), stomatal conductance (g s), and transpiration rate (E) were similar and all varied in a single-peak curve with increasing salinity, and they were lower than those of control only at salinity over 150 mM. Under AS, P N, g s, and E decreased sharply with rising salinity. The decrease of g s might cause the obvious decreases of E and intercellular CO2 concentration, and the increase of water use efficiency under both stresses. The Na+ content and Na+/K+ ratio in shoot increased and the K+ content in shoot decreased under both stresses, and the changing extents under AS were greater than those under SS. Thus SS and AS are two distinctive stresses with different characters; the destructive effects of AS on the growth and photosynthesis of wheat are more severe than those under SS. High pH is the key feature of the AS that is different from SS. The buffer capacity is essentially the measure of high pH action on plant. The deposition of mineral elements and the intracellular unbalance of Na+ and K+ caused by the high pH at AS might be the reason of the decrease of P N and g s and of the destruction of photosynthetic pigments.

Atomically dispersed metal catalysts are hailed as the most promising catalyst category for oxygen electrocatalysis. However, the challenges in regulating electronic configuration and unveiling the mechanism on the atomic scale are hindering their practical implementation. Herein, we modulate the Co d-orbital electron configuration by constructing the Ir–Co atomic pair toward boosted bifunctional activity. The as-developed dual-atom IrCo–N–C catalyst displays unprecedented activity with a half-wave potential of 0.911 V for oxygen reduction reaction and only 330 mV overpotential at 10 mA cm–2 for oxygen evolution reaction, outperforming the single-atom counterparts as well as the commercial Pt/C and Ir/C benchmarks. The impressive bifunctionality is also verified in a Zn–air battery prototype with an ultra-high cyclability over 450 cycles. Theoretical calculations are performed to shed light on the synergetic effects of the atomic pair site, where the incorporation of Ir atom alters the d-orbital energy level of Co and thus induces the re-arrangement of d-electron toward intensified spin polarization. As a result, the lower occupancy of dz2 orbital facilitates the electron acceptation from oxygen to form a stronger Co–O σ bond, thereby propelling faster reaction kinetics.

Abstract Graphene quantum dots (GQDs) have aroused great interest in the scientific community in recent years due to their unique physicochemical properties and potential applications in different fields. To date, much research has been conducted on the ingenious design and rational construction of GQDs‐based nanomaterials used as electrode materials and/or electrocatalysts. Despite these efforts, research on the efficient synthesis and application of GQDs‐based nanomaterials is still in the early stages of development and timely updates of recent research progress on new design concepts, synthetic strategies, and significant breakthroughs in GQDs‐based nanomaterials are highly desired. In light of the above, the effect of synthetic methods on the final product of the GQDs, the GQDs synthesis mechanism, and specific perspectives regarding the effect of the unique surface and structural properties of GQDs (e.g., defects, heteroatom doping, surface/edge state, size, conductivity) on the electrochemical energy‐related systems are discussed in‐depth in this review. Additionally, this review also focuses on the design of GQDs‐based composites and their applications in the fields of electrochemical energy storage (e.g., supercapacitors and batteries) and electrocatalysis (e.g., fuel cell, water splitting, CO 2 reduction), along with constructive suggestions for addressing the remaining challenges in the field.