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Air batteries are promising energy storage technologies that have gained continuous attraction due to their high energy densities. At present, investigations on anodes of air batteries are usually focused on various metals such as Li, Zn, Al. In contrast, the semiconductor anodes like Si and Ge are less investigated. Si-air battery possesses a high theoretical energy density and Ge-air battery has a high actual power density and ideal safety. Besides anodes, air cathodes where oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are also the key components in air batteries. To further promote the discharging performance and facilitate energy conversion/storage, semiconductor materials have been introduced in electrochemical cells like Li-O2 and Zn-air batteries. This review briefly summarizes semiconductor materials utilized in various air batteries, including the progress of Si-air and Ge-air batteries and recent advances in semiconductor cathodes catalysts. Finally, the remaining challenges and further perspective are discussed.

In all-polymer solar cells (APSCs), number-average molecular weights (Mns) of polymer donors and polymer acceptors play an important role in active layer morphology and photovoltaic performance. In this work, based on a series of APSCs with power conversion efficiency of approaching 10%, we study the effect of Mns of both polymer donor and polymer acceptor on active layer morphology and photovoltaic performance of APSCs. We select poly[4-(5-(4,8-bis(5-((2-butyloctyl)thio)thiophen-2-yl)-6-methylbenzo[1,2-b:4,5-b']dithiophen-2-yl)thiophen-2-yl)-5,6-difluoro-2-(2-hexyldecyl)-7-(5-methylthiophen-2-yl)-2H-benzo[d][1,2,3]triazole] (CD1) as the polymer donor and poly[4-(5-(5,10-bis(2-dodecylhexadecyl)-4,4,9,9-tetrafluuoro-7-methyl-4,5,9,10-tetrahydro3a,5,8,10-tetraaza-4,9-diborapyren-2-yl)thiophen-2-yl)-7-(5-methylthiophen-2-yl)benzo[c][1,2,5]thiadiazole] (PBN-14) as the polymer acceptor. The Mns of polymer donor CD1 are 14.0, 35.5 and 56.1 kg/mol, respectively, and the Mns of polymer acceptor PBN-14 are 32.7, 72.4 and 103.4 kg/mol, respectively. To get the desired biscontinueous fibrous network morphololgy of the polymer donor/polymer acceptor blends, at least one polymer should have high or medium Mn. Moreover, when the Mn of polymer acceptor is high, the active layer morphology and APSC device performance are insensitive to the Mn of polymer donor. The optimal APSC device performance is obtained when the Mn of both the polymer donor and the polymer acceptor are medium. These results provide a comprehensive and deep understanding on the interplay and the effect of Mn of polymer donors and polymer acceptors in high-performance APSCs.

In this manuscript, we investigate the effect of alkyl side chains of polymer donors on photovoltaic performance of all-polymer solar cells (all-PSCs) based on polymer acceptors containing a boron–...

The morphology of a polymer donor/polymer acceptor active layer in all-polymer solar cells (all-PSCs) has a big influence on photovoltaic performance. It is difficult to tune the active layer morph...

Optoelectronic polymers are always π-conjugated polymers consisting of C, H, N, S, and O elements. The main group element chemistry is a new tool to tune the optoelectronic properties of polymers. ...

The integrated micro proton exchange membrane fuel cells (μPEMFCs) were fabricated by constructing the hierarchical dot-type flow fields on Si wafers and then being compacted with the carbon black as gas diffusion layer (GDL) and Pt/C catalyst layer, which presents the simplicity and good device-integrity by replacing the traditional carbon paper or cloth as GDL and omitting the hot-press processing. The Si-compatible processes, including the template assembly of SiO2 spheres, dry etching, channel dicing, were elaborately manipulated to optimize the wafer-scale hierarchical flow field and thus industriously improve the fluids transport and gas distribution. Ultimately, the peak power of over 1W/cm2 was accomplished when the graphite bipolar plates were replaced by the hierarchical Si-based flow fields alone, while the maximum power of 354 mW/cm2 was successfully demonstrated in the integrated Si-based μPEMFCs with measured size of 4 cm2. This work not only broadens the application of PEMFCs to micro/nano-electro-mechanical systems (M/NEMS) or other Si-based electronic devices, but also provides guidelines for fabricating other metal-air batteries such as Zn-air batteries and Al-air batteries.

We report a p-π* conjugated organic molecule based on triarylborane as n-type organic semiconductor with unique alcohol solubility. Its favorable alcohol solubility even in the absence of polar side chains is mainly due to the large dipole moment and enhanced flexibility of the conjugated backbone once the boron atom is embedded. The p-π* conjugation directly affects the electronic structure as the LUMO is fully delocalized, including the boron atom, whereas the HOMO has the boron atom residing on a node. As a result, the molecule exhibits low-lying LUMO/HOMO energy levels of −3.61 eV/−5.73 eV paired with a good electron mobility of 1.37 × 10−5 cm2 V−1 s−1. We further demonstrate its application as an electron acceptor in alcohol-processed organic solar cells (OSCs). To our best knowledge, this p-π* conjugated molecule is the first alcohol-processable non-fullerene electron acceptor, a feature that is in strong demand for environmentally friendly processing of OSCs.

Indoor photovoltaic (IPV) cells receive increasing attention because of their promising applications as power sources for devices of the Internet of Things ecosystem. Under indoor artificial light illumination with narrow emission spectra, short-circuit current density is limited, and thus the IPV efficiency is highly dependent on open-circuit voltage (VOC). However, the VOC of various IPV cells, including silicon, III–V semiconductor, dye-sensitized, organic/polymeric, and perovskite photovoltaic cells, is mainly lower than 1 V due to their small optical bandgaps. Here, we report the first all-polymer IPVs using a blend of polymer donor and polymer acceptor as the active layer. Owing to the medium bandgap (Eg = 1.93 eV) and proper energy level alignment of the two polymers, the all-polymer IPV cell shows a high power conversion efficiency of 27.4% with an unprecedentedly high VOC of 1.16 V under fluorescent lamp illumination. This work opens up a research field of all-polymer photovoltaics for indoor light-harvesting applications.

The composites of platinum (Pt) nanoparticles (NPs) loaded on nitrogen-doped porous carbon (NPC) derived from ZIF-8 were successfully prepared based on double solvent impregnation and chemical reduction methods. By changing the calcination temperature and duration of ZIF-8, the concentration of nitrogen doping and bonding properties in the porous carbon can be well regulated, which is helpful to manipulate the crystal orientation of Pt nanoparticles and their dispersion and loading on the NPCs. Consequently, an improved oxygen reduction reaction (ORR) catalytic activity was successfully demonstrated in the optimized Pt@NPC composite with relatively lower content of Pt compared to the commercial catalyst Pt/C (20 wt%, JM). Moreover, the exceptional stability of the composite catalyst during ORR was experimentally verified by both the accelerated durability tests (ADT) and chronoamperometric i–t measurements. Intrinsically, pyridinic-N and graphitic-N were believed to be beneficial to the improved catalytic performance in the composite, while graphitic-N and pyridine-N-oxide were verified to be helpful to improve the stability as they can act as anchor of Pt NPs.

In this paper, we propose a self-calibration approach to stereo cameras with radial distortion from stereo image pairs of a common 3D scene. Based on the epipolar constraint in the stereo image pair, the intrinsic and extrinsic parameters of stereo cameras are estimated synchronously with a minimum number of nine image point correspondences. It is significant within a random sample consensus (RANSAC) scheme to cope with the outliers of feature matches efficiently and robustly. Then the inliers of the stereo image pair that have been determined after RANSAC are used to optimize the calibration parameters of stereo cameras. Furthermore, more accurate calibration results can be achieved with the joint optimization of multiple stereo image pairs. Both synthetic and real data are used to evaluate the performance of the proposed method, demonstrating that our method can calibrate stereo cameras with radial distortions efficiently and accurately.

This paper proposes a flexible method for camera self-calibration using affine correspondences and known relative rotation angle, which applies to the case that camera and inertial measurement unit (IMU) are tightly fixed. An affine correspondence provides two more constraints for the self-calibration problem than a traditional point correspondence, and the relative rotation angle can be derived from the IMU. Therefore, calibrating intrinsic camera parameters needs fewer correspondences, which can reduce the iterations and improve the algorithm’s robustness in the random sample consensus framework. The proposed method does not require rotational alignment between the camera and the IMU. This advantage makes our method more convenient and flexible. The experimental results of both synthetic data and publicly available real datasets demonstrate that our method is effective and accurate for camera self-calibration.

Si-air batteries have been gradually investigated in recent ten years due to their high theoretical capacity and ideal safety. In this work, to ameliorate the properties of Si-air batteries, models of Si electrodes were doped by Zn and Fe atoms respectively and density functional theory (DFT) calculations were performed. By constructing various models of Si-Zn/SiO2 and Si-Fe/SiO2 interfaces, the adsorption energies of SiO2 units on Zn or Fe-doped Si electrodes were first calculated. Meanwhile, the electrostatic difference potentials (EDP) and electron densities vary apparently across the interfaces. Additionally, the local device density of states (LDDOS) exhibit high intensities in the region of interfaces. Moreover, Zn and Fe dopants would introduce energy levels in the band gap and reduce the band gap of the interfaces according to the device density of state (DDOS) and projected local density of states (PLDOS). Finally, the I-V curves show that the current of the Si/SiO2/Si device can be enhanced by the introduction of Zn and Fe in the Si electrode. This work provides a method of surface modification to ameliorate the properties of Si-air batteries and assists to construct the Si-Zn and Si-Fe composite anodes in air batteries.

In this study, the effects of Ge modification of Si anodes in Si–Ge air batteries were investigated by building various atomic models of Si/Ge/GeO2 interfaces and performing density functional theory calculations. The results showed that the surface passivation could be restrained effectively by Ge modification because the adsorption energies of the GeO2 units on the Si–Ge anode increased when more Si atoms were substituted by Ge atoms. The electrostatic difference potentials, electron densities, and projected local density of states were also calculated for various Si/Ge/GeO2 interfaces to determine the differences in the properties of the Si-air battery and Si–Ge air battery. In addition, the I–V curves showed that the Si/Ge/SiO2/Si devices had higher currents than the Si/SiO2/Si device and the currents could be modulated by modification with Ge atoms. These findings provide insights into the mechanism responsible for the enhanced properties obtained by modification with Ge and they may facilitate the design of Si–Ge composite anodes for use in air batteries.

Electroanalysis is an effective monitoring method for organic pollution in environmental samples. However, chemical fouling with the formation of non-conductive fouled films easily occurs on the surface of the electrode during organic pollution detection that would inactivate the electrode and affect the detecting sensitivity of organic pollution. In this work, we found that zeolitic imidazolate framework-8 (ZIF-8) electrode can achieve effective degradation of non-conductive fouled films under the light illumination during electrochemical detection of some typical organic pollution (sulfamethoxazole (SMX), Bisphenol A (BPA) and diclofenac sodium (DS)). Profiting from the charge transfer capability and photoelectric characteristics, ZIF-8 electrode exhibits a lower detection limitation for organic pollution detection and superior regeneration property. The nice detection and superior regenerated property are mainly due to non-selective superoxide radical (·O2−) and hydroxyl radicals (·OH) mediation produced by ZIF-8 electrode under light illumination that can mineralize anodic fouled products and resume surface reactive sites. Compared with the single electrochemical determination, photo-assisted electroanalysis provides a stable monitoring and a renewable pathway for practical applications.

The anode supports of direct methanol fuel cell (DMFC) directly affect the energy conversion efficiency between methanol fuel and electric energy. Semiconductor-based supports have nice photoelectric property for photo-assisted electrocatalytic methanol oxidation, making it be a kind of promising support of Pt. However, the rapid recombination of semiconductor photogenerated carriers limits the methanol oxidation ability of Pt. Herein, the two-dimensional (2D) (001) TiO2 nanosheets doped by a small amount of atomic iron were prepared by a reproducible impregnation method as the anode support to decrease the recombination rate. The atomic iron sites doped 2D (001) TiO2 nanosheets electrode has a high electrocatalytic performance for methanol oxidation under UV light-excitation, which is 2.7 times higher than that in dark and 4.8 times than that of non-doped electrode. The nice activities of atomic iron sites doped 2D (001) TiO2 nanosheets can be attributed to the introduction of atomic iron which are beneficial for the separation of photogeneration carriers and producing more photogenerated holes for the generation of strong oxidizing hydroxyl radicals (•OH). During the process of electrocatalytic methanol oxidation, •OH can not only promote the photocatalytic methanol oxidation, but also attenuate the inactivation of Pt poisoned by COads. These results provide a strategy to further ameliorate the photo-assisted electrocatalytic property for methanol oxidation.

Photochemical oxidation is an effectively renewable method for fouled electrode in electrochemical detection of organic pollutant, while the renewable ability is subjected by the surface-bound radicals of electrode. Herein, ultrathin two-dimensional (2D) Bi2WO6 nanosheets are rationally applied to detect sulfamethoxazole (SMX) antibiotic. Ultrathin 2D Bi2WO6 nanosheets electrode shows efficient detection ability and a nice photochemical renewable ability under light illumination. Crystal phase analysis, radical analysis, surface observation and pollutant degradation performance reveal that active radicals are chiefly responsible for the outstanding photochemical regeneration ability of ultrathin 2D Bi2WO6 nanosheets. Our work provides an advanced and stable electrochemical monitoring approach and an efficient, simple and low-cost photochemical oxidation sensor for SMX detection.

Vision navigation has non-contact, high-precision and low-cost characteristics compared with other navigation method. This paper proposes a vision navigation method for planar moving platform in known scene based on two 2D-3D correspondences. Taking account of the arbitrary direction of camera and the relative pose between the camera and the platform, we propose a linear solver with unique solution, whose minimal number of requirement correspondences is 2 and can cope with arbitrary number of correspondences bigger than 2 directly. Our method is evaluated on both synthetic data and real-world data. The experimental results demonstrate that our method is high-accuracy and fast for vision navigation of planar moving platform.

Indoor photovoltaics (IPVs) are receiving great attention because they can power the wireless microelectronic devices needed for Internet of Things (IoTs) applications. Many polymer acceptors have been designed and synthesized for solar cell applications. In this manuscript, we study the application of three polymer acceptors in all-polymer indoor photovoltaic devices. The polymer acceptors containing boron-nitrogen coordination bond (B←N) have medium bandgap of 1.8–1.9 eV and proper the lowest unoccupied molecular orbital energy level (ELUMO) and the highest occupied molecular orbital energy level (EHOMO) alignment and consequently are very suitable for IPV application. Under fluorescent lamp illumination at the brightness of 2000 lux, the devices based on the polymer acceptors containing B←N unit show the open-circuit voltage of 1.08 V and a power conversion efficiency (PCE) of 23.2%. This performance is much higher than that of other imide-based polymer acceptors with small bandgap and wide absorption spectrum.

Progress in micro/nano-electro-mechanical system (M/NEMS) and microelectronics technologies urgently require the synchronous development of the micro/nano energy storage systems. Herein, a novel patterned Si/TiN/Ge electrode is fabricated on the Si substrate surface by the facile femtosecond-laser direct writing and the microelectronic thin film deposition techniques. The surface-engraved Si/TiN/Ge electrode displays superior cyclability and rate capability when evaluated as anode for lithium ion microbatteries (LIMBs). The patterned TiN interlayer can act as an effective buffer layer to optimize the Li ions storage in the Si substrate, and the introduction of the Ge nanocomposites would further enhance the areal capacity, thus eventually bring the improved electrochemical performance. Moreover, the Li ions storage behaviours are experimentally investigated from the post morphologies of all the cycled electrodes, and theoretically studied by the COMSOL Multiphysics simulations and the first principles calculations. These results would shed light on the new strategy to design and exploit other high-performance Si based LIMBs.

Metal–organic segments (MOSs) have been controllably synthesized to composite with Si nanorod (NR) arrays as electrodes in lithium ion batteries (LIBs). These kinds of MOSs are suggested to be derived from solution species such as [Zn(C4H6N2)Ac]+, [Zn(C4H6N2)2Ac]+ and [Zn(C3H4N2)(C4H6N2)Ac]+ as detected by electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS). It is found that solution concentration and growth time have significant effects on the MOS coating around Si NRs. The uniform coating of MOSs around Si NRs has been successfully produced at relatively low solution concentrations or for shorter growth time, which was proved to be helpful to enhance the capacity of the composite electrode up to ∼1.1 mA h cm−2 at a current density of 10 μA cm−2 and ∼0.5 mA h cm−2 on increasing the current density to 50 μA cm−2. Furthermore, at an even higher current density of 200 μA cm−2 (vs. initial 10 μA cm−2) the composite electrodes still can maintain more than 50% of the initial capacities. While, given a higher solution concentration or longer reaction time, large ZIF-61 crystals, a kind of metal–organic framework (MOF), would form on the top of Si NRs. Unlike MOSs, large ZIF-61 crystals fail to cover the Si NR homogeneously, and consequently the capacities of ZIF-61/Si NR composite electrodes are much lower than those of MOS/Si NR electrodes. This work not only demonstrates a simple method for Si surface modification to enhance its corresponding electrochemical performance, but also provides a potential general strategy for the coating of different surfaces by the cross-linking of metal nodes and organic ligands.

Triarylboranes that exhibit p-π* conjugation serve as versatile building blocks to design n-type organic/polymer semiconductors. A series of new molecular acceptors based on triarylborane is reported here. These molecules are designed with a boron atom that bears a bulky 2,4,6-tri-tert-butylphenyl (Mes*) substituent at the core and strong electron-withdrawing 2-(3-oxo-2,3-dihydroinden-1-ylidene)malononitrile (IC) units as the end-capping groups that are linked to the core by bithiophene bridges. Butyl or butoxy groups are introduced to the bithiophene units to tune the optoelectronic properties. These molecules show nearly planar backbones with highly localized steric hindrance at the core, low LUMO/HOMO energy levels, and broad absorption bands spanning the visible region, which are all very desirable characteristics for use as electron acceptors in organic solar cell (OSC) applications. The attachment of butyl groups to the bithiophene bridges brings about a slightly twisted backbone, which in turn promotes good solubility and homogeneous donor/acceptor blend morphology, whereas the introduction of butoxy groups leads to improved planarity, favorable stacking in the film state, and a greatly reduced band gap. OSC devices based on these molecules exhibit encouraging photovoltaic performances with power conversion efficiencies reaching up to 4.07 %. These results further substantiate the strong potential of triarylboranes as the core unit of small molecule acceptors for OSC applications.

The surface passivation of Ge(100) and Ge(111) anodes in Ge–air batteries with different doping types and concentrations is analyzed by density function theory (DFT) calculations. Compared with Ge(111) anodes, the surface passivation is restrained on Ge(100) anodes as they have larger binding energies with GeO2 layers. Meanwhile, doping would hinder the formation of a GeO2 layer on Ge anodes, especially for p-type doping, like B. The dissimilarities of the electrostatic potential differences and projected local density of states between the p-type Ge(100)/GeO2 and Ge(111)/GeO2 also reveal the origins of their distinct performances in Ge–air batteries. Furthermore, the I–V curves show that the Ge(100)/GeO2/Ge(100) device has a higher current than the Ge(111)/GeO2/Ge(111) device. This work would help to fundamentally comprehend the different electrochemical properties of Ge–air batteries with different orientations and doping and provide guidelines for the design of Ge anodes in Ge–air batteries.

Introducing cow manure compost as an amendment in landfill-leachate-contaminated soils is proved to be an effective technique for the immobilization of Cd in this study. Landfill-leachate-contaminated soil was collected from an unlined landfill in China and amended with a different blending quantity of cow manure compost (0, 12, 24, 36, and 48 g per 200 g soil), which was made by mixing cow manure and chaff at a ratio of 1/1 and maturing for 6 months. pH values of five different blending quantity mixtures increased by 0.2-0.4, and the organic matter levels increased by 2.5-7%, during a remediation period of 5 weeks. Four fractions of Cd named exchangeable Cd, reducible Cd, oxidizable Cd, and residual Cd in soil were respectively analyzed by a sequential extraction procedure. Introducing the cow manure compost application resulted in more than 40% lower exchangeable Cd but a higher concentration of oxidizable Cd in soils, and mass balance results showed nearly no Cd absorption by applied material, indicating that transformation of exchangeable Cd into oxidization forms was the main mechanism of Cd immobilization when cow manure compost was used as an amendment. The Pearson correlation showed that increasing of pH values significantly improved the efficiency of Cd immobilization, with a correlation coefficiency of 0.940 (p0.05). This is the first attempt at heavy metal immobilization in landfill-leachate-contaminated soil by cow manure compost, and findings of this work can be integrated to guide the application.Addition of cow manure compost (CMC) was effective in reducing exchangeable Cd in landfill-leachate-contaminated soils (LLCS). The immobilization effect of Cd was mainly assigned to the redistribution of labile soil Cd. Organic matter (OM) and pH value increased with CMC application. The pH values were more sensitive to Cd immobilization efficiency. It was proved that CMC can be safely and effectively used for the restoration of LLCS.

Functionalized graphene is prepared by an efficient and facile approach via diazo chemistry. The modification is observed spectroscopically, and improvements in the solubility and reactivity will expedite the application of graphene.

Perovskite solar cells are some of the most promising photovoltaic devices and they have experienced extraordinary progress in efficiency and fabricating technologies. Herein, we explore the effect of Co-doped NiOx hole transport layers on the electronic structure and photovoltaic properties of PSCs, which were deposited onto FTO substrates via DC magnetron sputtering at room temperature. Appropriate Co-doping can slightly regulate the optical band gap and the Fermi level position, leading to an increased potential cell performance. By virtue of continuously adjusting the power loaded onto the Co target, we can obtain the optimal atomic ratio of the Co:NiOx hole transport layer, and the PSC based on Co:NiOx exhibited a 25% higher efficiency than its undoped counterparts (from 9.46% to 12.61%). Therefore, these results demonstrate that Co is an appropriate dopant and the PSCs based on Co:NiOx layers have a good performance.

The adsorption and diffusion properties of Li/Na on the Si nanowire (NW) with substrate are analyzed by the density functional theory (DFT) calculations. The Li/Na prefers to adsorb on the corner of the Si NW with substrate and the adsorption energies on different sites vary from −1.32 eV to −0.74 eV. The diffusion pathways and corresponding energy barriers of lithium/sodium on the Si substrate and sidewall of the Si NW are calculated by the nudged elastic band (NEB) method. Moreover, when Li/Na moves around the Si NW, the Si NW would bend with the maximum displacement of ~0.76 A. Finally, the energy barriers are 0.61–0.81 eV when Li/Na diffuses across the Si NW, indicating the Si NW may be applied as anodes in both lithium and sodium ion batteries. This work would help to investigate the Li/Na adsorption and diffusion properties on various nanowires with substrates and provide guidelines for the design of Si anodes in sodium ion batteries.

In situ degradation of organic contaminants by Pd and electro-generated H2 and O2 overcomes the drawbacks to traditional Fenton process, and conducting heterogeneous catalyst of FeMgAl layered double hydrotalcite (LDH) further improved the efficiency and stability. Using bisphenol A (BPA) as the model contaminants, 90% removal can be achieved with 1200 mg/L Pd/Al2O3 and FeMgAl-2. The reusability was satisfying due to the very limited leaching of Fe ions at 0.1 ppm level. FeMgAl also amplified the window of pH for Pd-catalyzed in situ advanced oxidation processes (AOPs) from 3 by homogenous Fe(II) to 3–7 by FeMgAl LDH. The COD of landfill leachate effluent of the MBR system removed by about 52.3% by this system by the initial pH was 5. Characterizations revealed the distinguishing features associated with LDH structure such as large surface area, good stability, basic character, and strong linage among active sites were accounted for the remarkable performances over a wide pH window. Five reactive intermediates were observed and multiple degradation pathways were proposed in Pd-catalyzed in situ AOP for the first time. Interestingly, because of the unique role of Pd catalyst, these degradation pathways were clearly distinguished from traditional Fenton or Fenton-like AOPs and may provide a new approach of in situ heterogeneous AOPs for refractory contaminants in future.

Municipal solid waste (MSW) leachate contains various refractory pollutants that pose potential threats to both surface water and groundwater. This paper established a novel catalytic oxidation process for leachate treatment, in which OH is generated in situ by pumping both H2 and O2 in the presence of Pd catalyst and Fe2+. Volatile fatty acids in the leachate were removed almost completely by aeration and/or mechanical mixing. In this approach, a maximum COD removal of 56.7% can be achieved after 4 h when 200 mg/L Fe2+ and 1250 mg/L Pd/Al2O3 (pH 3.0) are used as catalysts. After oxidation, the BOD/COD ratio in the proposed process increased from 0.03 to 0.25, indicating that the biodegradability of the leachate was improved. By comparing the efficiency on COD removal and economical aspect of the proposed Pd-based in-situ process with traditional Fenton, electro-Fenton and UV-Fenton for leachate treatments, the proposed Pd-based in-situ process has potential economic advantages over other advanced oxidation processes while the COD removal efficiency was maintained.

3D micro/nanobatteries in high energy and power densities are drawing more and more interest due to the urgent demand of them in integrating with numerous micro/nanoscale electronic devices, such as smart dust, miniaturized sensors, actuators, BioMEMS chips, and so on. In this study, the electrochemical performances of 3D hexagonal match-like Si/Ge nanorod (NR) arrays buffered by TiN/Ti interlayer, which are fabricated on Si substrates by a cost-effective, wafer scale, and Si-compatible process are demonstrated and systematically investigated as the anode in sodium-ion batteries. The optimized Si/TiN/Ti/Ge composite NR array anode displays superior areal/specific capacities and cycling stability by reason of their favorable 3D nanostructures and the effective conductive layers of TiN/Ti thin films. Sodium-ion insertion behaviors are experimentally investigated in postmorphologies and elemental information of the cycled composite anode, and theoretically studied by the first principles calculation upon the adsorption and diffusion energies of sodium in Ge unit cell. The preferential diffusion of sodium in Ge structure over in Si lattice is evidently proved. The successful configuration of these distinctive wafer-scale Si-based Na-ion micro/nanobattery anodes can provide insight into exploring and designing new Si/Ge-based electrode materials, which can be integrated into micro-electronic devices as on chip power systems in the future.

Because of either thermal/chemical instability or high optical loss in noble metal nanostructures, searching for alternative plasmonic materials is becoming more and more urgent, considering the practical biosensing applications under various extreme conditions. In this work, titanium nitride (TiN), a low-loss metal-like material with both excellent thermal and excellent chemical stabilities, was proposed to composite with Ag hollow nanosphere (HNS) nanostructures as an effective surface-enhanced Raman scattering (SERS) substrate to realize both highly sensitive and highly stable molecular detection. Because of the multiple-mode local surface plasmon resonance around the spherical composite nanospheres and the "gap effect" derived from the ultrasmall nanogaps within the precisely controlled plasmonic arrays, an intensively enhanced local field was successfully induced on this SERS substrate. Combined with the unique charge transferring process between Ag and TiN, a synergistically enhanced SERS sensitivity involving both physical and chemical mechanisms was achieved. Especially, with the isolation of TiN, a time-durable Raman detection on these TiN-Ag HNS arrays was accomplished, showing great potential for practical applications.

Connected and airbag isolated Si-Ge nanorod (NR) arrays in different configurations have been fabricated on wafer scale Si substrates as anodes in micro-lithium ion batteries (LIBs), and the impacts of configurations on electrochemical properties of the electrodes were investigated experimentally and theoretically. It is demonstrated that the Si inner cores can be effectively protected by the connected Ge shells and contribute to the enhanced capacity by ∼68%, derived from an activation process along with the amorphization of the crystalline lattice. The first-principles calculations further verify the smaller forces on the Si layers at the atomic level during the restricted volume expansion with the covering of Ge layers. This work provides general guidelines for designing other composites and core-shell configurations in electrodes of micro-LIBs to accomplish higher capacities and longer cycle lives.

The rapid development of numerous microscale electronic devices, such as smart dust, micro or nano bio-sensors, medical implants and so on, has induced an urgent demand for integratable micro or nano battery supplies with high energy and power densities. In this work, 3D hexagonal bottle-like Si/Ge composite nanorod (NR) array electrodes with good uniformity and mechanical stability potentially used in micro or nano rechargeable Li-ion batteries (LIBs) were fabricated on Si substrates by a cost-effective, wafer scale and Si-compatible process. The optimized Ge nano-islands coated Si NR composite arrays as anode materials exhibit superior areal capacities and cycling performances by virtue of their favourable structural and improved conductivity features. The unique Si-based composite electrode in nanostructures can be technically and fundamentally employed to configurate all-solid-state Li-ion micro-batteries as on-chip power systems integrated into micro-electronic devices such as M/NEMS devices or autonomous wireless microsystems.