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As a high energy-consuming industry, it is especially important for electric power companies to manage carbon emissions well. This study analyzes the main problems of electric power companies in carbon asset management, and investigates the methods of intelligent, digital and transparent management of carbon emission situation using intelligent Internet of Things and blockchain technology. Carbon emission management based on blockchain technology can improve the accuracy and openness of carbon asset data and promote electric power companies to move forward to the low-carbon ecological era.

Correction for ‘Manipulation of oxygen evolution reaction kinetics of a free-standing CoSe2–NiSe2 heterostructured electrode by interfacial engineering’ by Muhammad Rauf et al., Sustainable Energy Fuels, 2022, 6, 5392–5399, https://doi.org/10.1039/D2SE01259F.

Liquid air energy storage (LAES) uses air as both the storage medium and working fluid, and it falls into the broad category of thermo-mechanical energy storage technologies. The LAES technology offers several advantages including high energy density and scalability, cost-competitiveness and non-geographical constraints, and hence has attracted a growing interest in recent years. As a result, several reviews have been published on the topic. However, these reviews covered little in the following aspects of LAES: dynamic simulation and optimisation, key components for LAES, LAES applications through integration, and unified economic and cost models for LAES. This article provides a comprehensive review on the LAES technology and fills the above gaps. Apart from applications in electrical grids such as peak-shaving, load shifting, and dealing with intermittency of renewable generation, the review also shows a diverse range of other LAES applications through integration, including waste heat and cold energy recovery and utilisation, multi-energy vector service provision, and sector coupling for chemical production and carbon capture. The review also leads to the recommendation of several areas for future research and development, including dynamic characteristics of whole LAES system integrated with renewables and end users; thermo-economic and dynamic optimization of stand-alone LAES and integrated systems; and experimental study on commercial systems.

Correction for ‘Tuning and understanding the electronic effect of Co–Mo–O sites in bifunctional electrocatalysts for ultralong-lasting rechargeable zinc–air batteries’ by Yi Guan et al., J. Mater. Chem. A, 2021, 9, 21716–21722, https://doi.org/10.1039/D1TA04408G.

Correction for ‘Long cyclic stability of acidic aqueous zinc-ion batteries achieved by atomic layer deposition: the effect of the induced orientation growth of the Zn anode’ by Zhisen Zeng et al., Nanoscale, 2021, 13, 12223–12232, https://doi.org/10.1039/d1nr02620h.

In this work, a selective wet etching process of Si to Si0.7Ge0.3 with TMAH solution to fabricate SiGe nanowires is systematically investigated. Initially, the 2.3% TMAH solution at 20 °C is applied for the as grown Si0.7Ge0.3/Si multilayers stack and a “rectangular” profile is achieved at the Si0.7Ge0.3 extremity due to its high selectivity. However, the reduction of Ge concentration due to the Ge interdiffusion caused by the high temperature anneal treatment will attain a reduced selectivity of Si to Si0.7Ge0.3 and a “rounding” Si0.7Ge0.3 extremity profile. Moreover, the profile of the upper Si0.7Ge0.3 extremity is clearly worse than the bottom one. This is because the Ge concentration of upper Si0.7Ge0.3 is 1.5% lower and the Ge interdiffusion of the upper Si0.7Ge0.3 is slightly worse. After increasing the TMAH concentration to 25%, both the upper and bottom Si0.7Ge0.3 extremity can achieve a “rectangular” extremity profile with an almost the same Si0.7Ge0.3 loss ~ 1.5 nm per side. Compared with 2.3% TMAH concentration, the Ge concentration of the etching off SiGe film can be reduced from lower than 29% to lower than 24% using the 25% TMAH solution at 20 °C. Therefore, the 25% TMAH solution at 20 °C is chosen as the optimal selective etching condition for the thermal treated Si0.7Ge0.3/Si multilayers stack samples. Finally, a vertical stacked double SiGe nanowire structure is successfully prepared by utilizing this optimal process condition. This indicates that it is a practicable technique for the selective wet etching of Si in fabricating SiGe nanowires.

We study a continuous-wave sum-frequency blue laser operating at 484 nm. The laser elaborated is based on the intracavity pumping technology. A 912 nm laser produced by an end-pumped Nd:GdVO4 crystal, using an 808 nm fiber-coupled laser diode, is employed to pump an Yb:YAG crystal in the cavity to achieve the simultaneous oscillations in 912 and 1030 nm lasers. An intracavity sum-frequency achieved in a type-I phase-matched BIBO crystal is used to obtain the 484 nm blue laser output. In our experiment, we apply a linear coaxial laser resonator structure. As a result, we obtain a sumfrequency blue laser output of 317 mW at a pump power of 25 W. The slope efficiency of the designed laser is 2.8%, and the beam quality factors are 1.34 in the X direction and 1.36 in the Y direction, respectively, with the power fluctuations about 3.8% within four hours.

Ultrathin Ni germanosilicide liner ( x Ge y /p+-SiGe:B contacts show improved specific contact resistivity ( $\rho _{\text {c}}$ ) with respect to conventional TiSi x Ge y /p+-SiGe:B ones. It is further demonstrated that the $\rho _{\text {c}}$ of NiSi x Ge y /p+-SiGe:B contacts is correlated with both Ni thickness and post metal anneal (PMA). Utilizing Ge preamorphization implant (Ge PAI) followed by B ion implant (B I/I), the active concentration of B dopants is enhanced from $1\times 10^{{20}}$ cm $^{-{3}}$ for reference to $6\times 10^{{20}}$ cm $^{-{3}}$ . Consequently, a remarkably lowered $\rho _{\text {c}}$ of $\sim 7.42\times 10^{-{9}} \,\Omega \cdot $ cm2 is achieved for NiSi x Ge y /p+-SiGe:B contacts, where Ni layer is 20 A and PMA temperature is 500 °C.

This article theoretically investigates the impact of charges at the ferroelectric/interlayer interface on the depolarization field of ferroelectric FET (FeFET) with metal/ferroelectric/interlayer/Si gate structure. The interfacial charges include fixed charges and trapped/detrapped charges. We find that the positive or negative interfacial charges (~1013 cm−2) can align the directions of the depolarization field and corresponding polarization in the ferroelectric. This article may provide insight into the device design of FeFET.

Background RING (Really Interesting New Gene) zinc finger (RING-zf) proteins belong to an important subclass of zinc fingers superfamily, which play versatile roles during various developmental stages and in abiotic stress responses. Based on the conserved cysteine and histidine residues, the RING-zf domains are classified into RING-HC (C3HC4), RING-H2 (C3H2C3), RING-v, RING-D, RING-S/T, RING-G, and RING-C2. However, little is known about the function of the RING-zfs of wheat. Results In this study, 129 (93.5%) of 138 members were found in nucleus, indicating TaRING-zf were primarily engaged in the degradation of transcription factors and other nuclear-localized proteins. 138 TaRING-zf domains can be divided into four canonical or modified types (RING-H2, RING-HC, RING-D, and RING-M). The RING-M was newly identified in T. aestivum, and might represent the intermediate other states between RING-zf domain and other modified domains. The consensus sequence of the RING-M domain can be described as M-X2-R-X14-Cys-X1-H-X2-Cys-X2-Cys-X10-Cys-X2-Cys. Further interspecies collinearity analyses showed that TaRING-zfs were more closely related to the genes in Poaceae. According to the public transcriptome data, most of the TaRING-zfs were expressed at different 15 stages of plant growth, development, and some of them exhibited specific responses to drought/heat stress. Moreover, 4 RING-HC (TraesCS2A02G526800.1, TraesCS4A02G290600.1, TraesCS4B02G023600.1 and TraesCS4D02G021200.1) and 2 RING-H2 (TraesCS3A02G288900.1 and TraesCS4A02G174600.1) were significantly expressed at different development stages and under drought stress. These findings provide valuable reference data for further study of their physiological functions in wheat varieties. Conclusions Taken together, the characterization and classifications of the TaRING-zf family were extensively studied and some new features about it were revealed. This study could provide some valuable targets for further studies on their functions in growth and development, and abiotic stress responses in wheat.

Although the design and synthesis of efficient electrocatalysts for the hydrogen evolution reaction (HER) are highly desirable, severe challenges still need to be addressed. Herein, ultrathin MoS

For better design and optimization of the heat exchanger (HX), forced convective heat transfer and flow characteristics of supercritical carbon dioxide (SCO2) in a water-cooled experimental counter-flow tube-in-tube HX were studied numerically with three-dimensional Reynolds-averaged Navier-Stokes equations and shear stress transport (SST) turbulence model by using computational fluid dynamics method in ANSYS CFX. With a sole tube model of the HX, effects of SCO2 inlet pressure, mass flux, tube diameter and wall heat flux on SCO2 mean heat transfer coefficient (MHTC) were investigated. Influences of turbulence models and discretisation schemes of the advection terms in the SST model, wall temperature of conservative and hybrid values in CFX-Post on MHTC were clarified, and buoyancy effect in the horizontal HX was explored. The SST model can achieve better agreement with the experimental MHTCs of SCO2 than the other models. The buoyancy effect can improve MHTC by the secondary flows in the tube.

The acid tolerance of Streptococcus mutans plays an important role in its cariogenic process. Streptococcus mutans initiates a powerful transcriptional and physiological adaptation mechanism, eventually shielding the cellular machinery from acid damage and contributing to bacterial survival under acidic stress conditions. Although S. mutans contains complex regulatory systems, existing studies have shown that S. mutans, unlike Escherichia coli, cannot maintain a neutral intracellular environment. As the pH of the extracellular environment decreases, the intracellular pH decreases in parallel. There is insufficient knowledge regarding the acid resistance of the intracellular proteins of S. mutans, particularly when it comes to the key cytoskeletal division protein FtsZ. In this study, the data showed that S. mutans had similar cell division progress in acidic and neutral environments. The splitting position was in the middle of cells, and the cytoplasm was divided evenly in the acidic environment. Additionally, the tread milling velocity of S. mutans FtsZ in the middle of cells was not affected by the acidic environment. Streptococcus mutans FtsZ had higher GTPase activity in pH 6.0 buffer than in the neutral environment. Furthermore, the polymerization of S. mutans FtsZ in the acidic environment was more robust than that in the neutral environment. After two particular amino acids of S. mutans, FtsZ amino acids were mutated (E88K, L269K), the polymerization of S. mutans FtsZ in the acidic environment was significantly reduced. Overall, S. mutans FtsZ exhibited higher functional activity in pH 6.0 buffer in vitro. The acid resistance of S. mutans FtsZ is affected by its particular amino acids.

Background: The CCHC zinc finger proteins (CCHC-ZFPs) are transcription factors that play versatile roles in plant growth, development, and responses to biotic/abiotic stress. However, little is known about the CCHC-ZF genes in bread wheat (Triticum aestivum), an important food crop.Results: In this study, 50 TaCCHC-ZF genes were identified and distributed unevenly on 21 wheat chromosomes. According to the phylogenetic features, the 50 TaCCHC-ZF genes were classified into eight groups with specific motifs and gene structures. 43 TaCCHC-ZF genes were identified as segmentally duplicated genes that formed 36 segmental duplication gene pairs. Additionally, the collinearity analyses between wheat and eight other representative plant species showed that wheat had closer phylogenetic relationships with monocots compared to dicots. A total of 636 cis-elements related to environmental stress and phytohormone responsiveness were identified in the promoter of TaCCHC-ZF genes. Moreover, GO enrichment results revealed that all 50 TaCCHC-ZF genes were annotated under metal ion binding and nucleic acid binding. 91 miRNA binding sites within the 34 TaCCHC-ZF genes were identified by miRNA targets analyses, indicating that the expression of TaCCHC-ZF genes could be regulated by the miRNAs. Based on published transcriptome data, 38 TaCCHC-ZF genes were identified as DEGs, and 15 TaCCHC-ZF genes among them were verified by qRT-PCR assays, which showed response to drought, heat, or simultaneous response of them.Conclusions: This study systematically explored the gene structures, evolutionary characteristics, and potential roles during environmental responses of TaCCHC-ZF genes, providing a foundation for further investigation and application of TaCCHC-ZF genes in the molecular breeding of T. aestivum.

The present work proposed a novel two-stage carbon dioxide hydrate-based vapor-compression refrigeration system. The proposed system applied pure carbon dioxide hydrate as the primary refrigerant and arranged both of hydrate formation and dissociation at the low-pressure stage. The thermodynamic and economic models were developed and then performances of the proposed system using load-levelling storage and full storage operations were evaluated and compared with those of a conventional carbon dioxide single-stage vapor-compression refrigeration system, which is treated as the baseline and with no energy storage. The simulation results indicate that the design capacity of the proposed system using full storage is the largest among the three systems, but with lowest operation cost, and with the incentivization of electricity prices ratio of on and off-peak this cost savings would raise significantly. Noted that the bill structure reveals the load-levelling storage system saves most on the water consumption. Due to the dominant expenditure on the two compressors, compare with the baseline system, the initial capital cost of the full storage system was 75.5% higher, whereas that of the levelling-load storage system was only 21.5% higher. Finally, this paper discussed the economic feasibility on the initial capital cost for the proposed system and developed an indication map to predict the profit years in case of that the new system using load-levelling storage operation replaces the baseline system assuming a system lifetime of 15 years under different electricity prices ratios.

Fast characterization methods are utilized to investigate DC and AC negative bias temperature instability (NBTI) characteristics in pMOSFETs with different TiN capping layer thicknesses ( ${t} _{\mathrm{ TiN}}$ ). The impacts of ${t} _{\mathrm{ TiN}}$ scaling on the threshold voltage shift ( ${\Delta }\text{V}_{\mathrm{ T}}$ ), pre-existing hole traps ( ${\Delta }\text{V}_{\mathrm{ HT}}$ ), generated traps (GTs), and their relative contributions are studied. The time exponents of ${\Delta }\text{V}_{\mathrm{ T}}$ and GTs, and the impacts of stress voltage, temperature, frequency, and duty cycle on the NBTI degradation are analyzed. DC and AC NBTI degradations increase with ${t} _{T}{}_{iN}$ . When ${t} _{\mathrm{ TiN}}$ is scaled down from 3 nm to 1 nm, the maximum operation field is improved by 60%, which originates from the reduction in both ${\Delta }\text{V}_{\mathrm{ HT}}$ and GTs. Moreover, we experimentally demonstrate that bulk trap generation is an ${f}$ -dependent process and that its relative contribution to ${\Delta }\text{V}_{\mathrm{ T}}$ increases with ${t} _{\mathrm{ TiN}}$ , which is an important factor for the improvement of NBTI through ${t} _{\mathrm{ TiN}}$ scaling.

Bionic electronic synapses with weight-modulation properties are promising alternative candidates when compared with traditional CMOS based neuromorphic hardware when building at-scale neural networks for efficient neuromorphic computing. In this Letter, due to the partial polarisation switching of multi-domain properties in polycrystalline Zr-doped HfO2 (HZO) ferroelectric materials, a capacitor-based bionic synapse was proposed, which showed multi-level capacitance modulation characteristics. By switching the voltage-controlled polarisation, the capacitance was gradually modulated via the variation of net polarisation vectors in the HZO layer. The potentiation and depression properties can be achieved with better linearity, symmetry and multiple states. This Letter laid the groundwork for realising the high-density integration neuromorphic computing system by using ferroelectric capacitors as the bionic synapse.

In this letter, we present an experimental study on the frequency ( f ) dependence of trap generation under AC negative bias temperature instability (NBTI) stress in Si p-channel fin field-effect transistors (p-FinFETs), by adopting the direct-current current voltage (DCIV) method and an energy profiling technique. The interface trap generation ( $\Delta ~\text{N}_{IT}$ ) and bulk trap generation ( $\Delta ~\text{N}_{OT}$ ) are separated from the measured DCIV data and their ${f}$ dependences are independently investigated. The DCIV results indicate that the observed strong ${f}$ dependence of trap generation is primarily attributed to the ${f}$ -dependent $\Delta ~\text{N}_{OT}$ that exhibits a 36% reduction when ${f}$ increases from 10 Hz to 1 MHz. Furthermore, this ${f}$ -dependent $\Delta ~\text{N}_{OT}$ is mainly distributed between ${\text{E}_{v}}$ and ${\text{E}_{i}}$ , and exhibits a visible ${f}$ -dependent peak of energy density around ${\text{E}_{c}}$ .

A coupled approach between the conventional computational fluid dynamics platform COMSOL and an in-house-developed direct numerical simulation code DigiDiss is presented to study the dissolution kinetics of an irregular-shaped particle in a stirred cuvette. The complex flow dynamics from COMSOL were imported into DigiDiss as an initial flow condition. A digitised 3D particle structure scanned and reconstructed by X-ray micro-tomography was used in the dissolution simulation. A quantitative assessment of the simulation results was made using as a reference experimental data and a theoretical calculation based on the shrinking spherical model with different flow velocity profiles near the particle. The comprehensive agreement demonstrates the coherence of the simulation method in reproducing the experimental behaviour and is seen as a step closer towards developing a computer software design aide to help with formulation development.

The scaling of interconnect dimensions is becoming increasingly difficult due to the fast rise of line/via resistance. To alleviate this problem, Co has a high potential as an alternative material to Cu or W in metallization schemes. In this article, Co is used as local interconnects, and Co–Ti is proposed as a single barrier/liner to replace the conventional thick TiN/Ti bilayer. The samples with and without Co–Ti were fabricated to investigate the barrier property of Co–Ti. Meanwhile, the reaction mechanism between Co/Co–Ti and Si was comprehensively studied. In order to further evaluate the barrier property of Co–Ti, the samples were annealed at 500 °C for different durations, including 1, 30, and 60 min. Interfacial quality, elemental distribution, and Co spikes were analyzed by cross-sectional and plane-view transmission electron microscopy (TEM) in combination with corresponding electron energy loss spectroscopy (EELS) mapping. Furthermore, refined transmission line model (RTLM) structures were employed to extract the specific contact resistivity ( $\rho _{c}$ ) of as-fabricated devices with different Co:Ti atomic ratios. Achieved results demonstrate that as a single barrier/liner, Co0.65Ti0.35 is highly effective in preventing Co diffusion into Si substrate, thus realizing a uniform Co0.65Ti0.35/n+-Si interface, spike-free contacts, and ultralow $\rho _{c}$ of $2.3 \times 10^{-8} \Omega {-}cm^{2}$ .

2 μm/3 μm laser has been extensively applied to the fields of medical treatment, communication and detection. In this paper, the genetic algorithm is innovatively used to solve the fiber power transmission equation, which improves the accuracy of simulation results. According to the simulation results, a dual-wavelength Er3+:ZBLAN fiber laser based on composite Fabry-Perot (F-P) cavity was designed and constructed. A stable continuous dual-wavelength output was obtained with a pump power of 50 W. The center wavelengths were 2.79 μm and 1.59 μm, respectively, the maximum output powers were 8.19 W and 2.8 W, respectively, the slope efficiencies were 17.7% and 7.17%, respectively, and the stability of the wavelengths in 2 h were 4.6% and 3.1%, respectively.

Creating oxygen vacancies to tune the surface electronic structure is a feasible approach to enhance the electrocatalytic activities of noble-metal-free transition-metal oxides for Li–O2 batteries....

The impact of the field reduction effect on negative bias temperature instability (NBTI) parameter characterization and lifetime prediction was quantitatively studied in p-MOSFETs with a sub-1 nm equivalent oxide thickness (EOT). By comparing NBTI results under constant field stress and constant voltage stress, the field reduction effect was found to become severer at higher VG-STR and ${T}$ and cause a reduction in the voltage acceleration factor (VAF) at higher VG-STR and a reduction in activation energy EA at higher ${T}$ under constant voltage stress. To accurately evaluate NBTI lifetime, a modified NBTI model with field reduction correction (FRC) was proposed, and the 10-year NBTI degradation of a 32-stage ring oscillator was simulated. The results showed that the conventional model without including FRC had a worse prediction capability and overestimated frequency degradation for a ring oscillator. It is necessary to use an NBTI model with FRC for NBTI lifetime prediction of devices with a sub-1 nm EOT.

Hollow carbon spheres (HCSs) have attracted great attention for their unique structure, but they perform unsatisfactory rate capacity for lack of mesopore. Here, we propose a novel strategy for fabricating the HCSs with macro-meso-microporous hierarchical pore structure, without etching and alkali activation. Our results show that HCSs can deliver a high gravimetric energy density of 6.2 Wh·kg−1 at the power density of 25 W·kg−1, as well as the energy density reaches up to 3.6 Wh·kg−1 at a high power density of 2.2 kW·kg−1. Moreover, assembled into micro-supercapacitor, HCSs perform a high areal capacitance of 15.4 mF·cm−2 at 0.2 mA·cm−2. Such excellent electrochemical performances of HCSs should be ascribed to the well-balanced pore distribution, which have been revealed by the electrochemical impedance spectroscopy and equivalent series resistance. It is believed that such advanced hollow carbonaceous materials are not only suitable for supercapacitors, but also be expected to apply for Li–S battery, sensor and drug delivery.

Retarding filed analyzers (RFAs) measure the ion velocity distribution in edge plasmas, leading to an estimate of the ion temperature and space potential through curve fitting. This paper describes...

To improve the high reversibility of lithium–air batteries, an air electrode needs to have excellent electrochemical performance and spatial structure. Ni3S2 nanoparticles are loaded onto an N,S-doped pearl chain tube (N,S-PCT) by a method called quasi-chemical vapor deposition (Q-CVD). Additionally, N and S are doped during the synthesis process, thereby forming an ideal pipe rack-like structure. The large amount of space in the tube rack can provide sufficient storage to act as a buffer for the discharge products, and the interconnected tubes can effectively promote the dispersion of O2 and electrolyte. The addition of Ni3S2 nanoparticles effectively reduces the charge transfer resistance, thereby increasing the electron mobility of the cathode. Ni3S2@N,S-PCT cathodes effectively improve the cycling and high-rate performance of lithium–air batteries, demonstrating an ultrahigh discharge capacity of 16 733.7 mA h g−1 at a current density of 400 mA g−1 and an ultrahigh discharge capacity of 5088.1 mA h g−1 at a current density of 1000 mA g−1. When the cut-off capacity is 1000 mA h g−1, the battery with the Ni3S2@N,S-PCT-800 electrode can achieve cycling stability for 148 cycles. This research provides a new solution for the design of lithium–air batteries with high electrocatalytic performance.

Li ion conducting garnets have been attracting considerable interest for use as the electrolyte in all solid-state batteries, due to their high ionic conductivity and wide electrochemical stability window. Consequently, there have been a number of doping studies aimed at optimising the conductivity, focusing on both doping in Li7La3Zr2O12 and Li5La3(Nb/Ta)2O12 systems. In this paper, we report a detailed study of Pr doping in Li5La3Nb2O12, and show that this is a rare example of an ambi-site dopant, being able to be doped onto either the La or Nb site. Interestingly the resultant Pr oxidation state is determined by the site substitution, with oxidation states of 3+ for the La site, and 4+ for the Nb site. While the conductivity is essentially unchanged for the La site substitution, Pr4+ substitution on the Nb site leads to a large increase in the conductivity associated with the increase in Li content (Li5+xLa3Nb2−xPrxO12) up to 0.56 mS cm−1 (at 50 °C) for x = 0.8. Overall, this work highlights the flexibility of these garnet materials to doping, and suggests that further consideration of site substitution be considered for other dopants.

In this study, FeOx and CoOx thin films were successively and uniformly coated on high-surface-area carbon nanotubes by plasma-enhanced atomic layer deposition, which formed a heterojunction of the two oxides. As an electrocatalyst in the oxygen evolution reaction (OER), CoOx/FeOx/CNTs showed excellent electrocatalytic performance in terms of catalytic activity and stability. The overpotential of CoOx/FeOx/CNTs in OER was only 308 mV at 10 mA cm−2, which was lower than those of the pure oxides: CoOx/CNTs (392 mV) and FeOx/CNTs (406 mV). The as-prepared electrocatalyst also displayed better stability than the reference RuO2 material, with almost no attenuation of current density in contrast to the 10% loss seen with RuO2. The OER performance of CoOx/FeOx/CNTs was superior to those of its oxide components due to the formation of heterojunction, which led to a smoother reaction path and a lower overpotential for OER compared to pure oxides, as supported by the density-functional theory (DFT) calculations. These results provide a new direction for the preparation of electrocatalysts for metal–air batteries and water splitting reactions.

N-Doped porous tremella-like Fe3C/C electrocatalysts derived from metal-organic frameworks (MOFs) were fabricated via a facile approach. The simply designed catalytic materials have unique fluffy multilayer interconnected porous morphology, which provides a large specific surface area and effectively prevents the agglomeration of nanoparticles. These special features create more active sites (Fe-Nx) on the surface of the electrocatalysts for oxygen reduction reaction (ORR) and the presence of the Fe-Nx active sites was verified via X-ray photoelectron spectroscopy. The effect of Fe intake through pyrolysis of MOFs materials was also studied and the composite with 0.04 g Fe source exhibited excellent ORR performance, a very small hydrogen peroxide yield, and followed the four-electron transfer pathway. The ORR activity of the electrocatalyst is comparable to that of commercial Pt/C, while the stability is even better than the latter in an alkaline solution. The facile method of preparing a multilayer porous N-doped tremella-like Fe3C/C electrocatalyst is a promising electrode material for a wide range of applications in fuel cells and metal-air batteries.

In this work, SiGe Fin formation technique using shallow trench isolation (STI) first or STI last strategy for the high mobility channel FinFET device is systematically investigated. A 20 nm width and 35 nm height high crystalline quality of the Si0.7Ge0.3 Fin formation for STI first scheme is demonstrated by utilizing a new developed Si Fin etching, Si Fin recess and SiGe selective epitaxial growth process. For the STI last strategy, a novel chemical mechanical planarization (CMP) treated three-layer SiGe strain relaxed buffer (SRB) is successfully fabricated and a 50 nm high crystal quality and atomically smooth surface Si0.5Ge0.5 layer on this SRB is attained. Moreover, a spike annealing is employed to avoid the Si0.5Ge0.5 Fin oxidation during STI densification with an acceptable STI etching rate. However, both a spike annealing and a lower temperature of traditional furnace at 850 °C or 750 °C suffer micro-trench issue during the Fin reveal process. Therefore, a new developed process, named as STI recess first, is developed to resolve both thermal instability and micro-trench issue at the same time. A minor Si0.5Ge0.5 Fin loss with a sharp Si0.7Ge0.3 SRB/Si0.5Ge0.5 interfaces for STI last scheme is realized by utilizing this new developed STI recess first process.

A dual-wavelength laser operating at 912 nm/1030 nm for the first time using a compact intracavity cascade pumping structure is set up The laser system model was designed and built for testing. The proposed system employs a coaxial linear cavity structure and uses a fiber-coupled 808 nm laser diode (LD) end-pumped Nd:GdVO4 crystal to obtain a 912 nm laser, which then pumped Yb:YAG crystal directly in the cavity to produce a 1030 nm laser. When the LD pump power at 808 nm is 25 W, a 0.97 W laser at 912 nm and a 1.33 W laser at 1030 nm are obtained, respectively. The corresponding optical to optical conversion efficiency is 9.2%. The beam quality factors M2 of 912 nm and 1030 nm lasers at maximum output power is measured to be 1.19 and 1.23.