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With the gradually increasing requirement for freshwater, capacitive deionization (CDI) as a burgeoning desalination technique has gained wide attention owing to its merits of easy operation, high desalination efficiency, and environmental friendliness. To enhance the desalination performance of CDI, different CDI architectures are designed, such as membrane CDI, hybrid CDI, and flow-electrode CDI. However, these CDI systems have their own drawbacks, such as the high cost of membranes, capacity limitation of carbon materials and slurry blockage, which severely limit their practical application. Notably, rocking-chair CDI (RCDI) composed of symmetric electrode materials delivers excellent desalination performance because of its special dual chamber structure, which can not only break through the capacity limitations of carbon materials, but also deliver a continuous desalination process. Although RCDI showcases high promise for efficient desalination, few works systematically summarize the advantages and applications of RCDI in the desalination field. This review offers a thorough analysis of RCDI, focusing on its electrode materials, structure designs and desalination applications. Furthermore, the desalination performances of RCDI and other CDI architectures are compared to demonstrate the advantages of RCDI and the prospect of RCDI is elucidated.

Covalent organic frameworks (COFs) with customizable geometry and redox centers are an ideal candidate for supercapacitors and hybrid capacitive deionization (HCDI). However, their poor intrinsic conductivity and micropore-dominated pore structures severely impair their electrochemical performance, and the synthesis process using organic solvents brings serious environmental and cost issues. Herein, a 2D redox-active pyrazine-based COF (BAHC-COF) was anchored on the surface of graphene in a solvent-free strategy for heterointerface regulation. The as-prepared BAHC-COF/graphene (BAHCGO) nanohybrid materials possess high-speed charge transport offered by the graphene carrier and accelerated electrolyte ion migration within the BAHC-COF, allowing ions to effectively occupy ion storage sites inside BAHC. As a result, the BAHCGO//activated carbon asymmetric supercapacitor achieves a high energy output of 61.2 W h kg−1and a satisfactory long-term cycling life. More importantly, BAHCGO-based HCDI possesses a high salt adsorption capacity (SAC) of 67.5 mg g−1and excellent long-term desalination/regeneration stability. This work accelerates the application of COF-based materials in the fields of energy storage and water treatment.

The open NASICON framework and high reversible capacity enable Na3V2(PO4)3(NVP) to be a highly promising cathode candidate for sodium-ion batteries (SIBs). Nevertheless, the unsatisfied cyclic stability and degraded rate capability at low temperatures due to sluggish ionic migration and poor conductivity become the main challenges. Herein, excellent sodium storage performance for the NVP cathode can be received by partial potassium (K) substitution and multiwalled carbon nanotube (MWCNT) cross-linking to modify the ionic diffusion and electronic conductivity. Consequently, the as-fabricated Na3–xKxV2(PO4)3@C/MWCNT can maintain a capacity retention of 79.4% after 2000 cycles at 20 C. Moreover, the electrochemical tests at −20 °C manifest that the designed electrode can deliver 89.7, 73.5, and 64.8% charge of states, respectively, at 1, 2, and 3 C, accompanied with a capacity retention of 84.3% after 500 cycles at 20 C. Generally, the improved electronic conductivity and modified ionic diffusion kinetics resulting from K doping and MWCNT interconnecting endows the resultant Na3–xKxV2(PO4)3@C/MWCNT with modified electrochemical polarization and improved redox reversibility, contributing to superior performance at low temperatures. Generally, this study highlights the potential of alien substitution and carbon hybridization to improve the NASICON-type cathodes toward high-performance SIBs, especially at low temperatures.

• A dual-strategy, F substitution, and the construction of three-dimensional nitrogen-doped conductive frameworks were employed for the NVP cathode. • The optimized NVP cathode demonstrates excellent electrochemical performance at both room and low temperatures. • The structure characterization and density functional calculations demonstrate its increased crystal stability and improved ionic/electronic conductivity. Benefitting from its unique NASICON-type framework, the Na 3 V 2 (PO 4) 3 (NVP) cathodes have aroused extensive interest and have been deemed as the promising cathode candidate for sodium-ion batteries (SIBs). Unfortunately, the poor electronic conductivity, combined with the undesirable volume variations, seriously hinders the practical application of NVP cathode, especially at low temperatures. Herein, a dual-strategy, F substitution accompanied by V vacancies and the construction of three-dimensional (3D) nitrogen-doped carbonaceous frameworks (NC), were employed for the NVP cathode (F-NVP/C@3DNC). The former can remarkably decrease the particle size and enhance Na+ migration capability, increasing the ionic conductivity. Meanwhile, the electronic connection and effective buffering can be obtained from the latter, strengthening the electrode integrity. Consequently, up to 100 cycles at 0.1 A g–1, a reversible capacity of 113.8 mAh g–1, approaching the theoretical value (117 mAh g–1), is demonstrated, accompanied by impressive capacity retentions at 1.0 (93.75% after 4800 cycles) and 20.0 A g–1 (92.7% after 1000 cycles). More importantly, even at –20 °C, a superior specific capacity (102.6 mAh g–1 after 100 cycles at 0.1 A g–1) and high capacity retention (86.6% at 20.0 A g–1 up to 1000 cycles) can still be obtained simultaneously. Significantly, the design of F-NVP/C@3DNC provides insights for the fabrication of polyanion cathodes for applications at low temperatures with modified structure stability and reaction kinetics. [Display omitted] [ABSTRACT FROM AUTHOR]

Flexible battery with a smart electrochromic function of changing color in the electrochemical process reveals great application potentials in the field of intelligent electronics. However, Ni//Zn battery with an electricity visual alerting function has seldom been reported by now. Herein, we designed a flexible Ni//Zn battery, assembled by the NiCo bimetallic hydroxide/Ni/indium tin oxide (NiCo BH/Ni/ITO) flexible electrode with an electrochromic feature. By optimizing the thickness of the middle Ni layer, the NiCo BH/Ni/ ITO electrode shows a coloration efficiency of 59.89 cm2C−1and a capacity of 7.15 µA h cm−2at a current density of 0.1 mA cm−2. Correspondingly, the flexible electrochromic Ni//Zn battery shows a high energy density of 12.69 µW h cm−2at a power density of 160 µW cm−2, outperforming those of transparent flexible supercapacitors and electrochromic batteries reported in literatures. Moreover, the flexible electrochromic Ni//Zn battery displays reversible color change during charging and discharging processes, rendering it a novel function to monitor the battery residual electricity by visual inspection.

As an emerging carbon-based material, carbon quantum dots (CQDs) have shown unstoppable prospects in the field of bionic electronics with their outstanding optoelectronic properties and unique biocompatible characteristics. In this study, a novel CQD-based memristor is proposed for neuromorphic computing. Unlike the models that rely on the formation and rupturing of conductive filaments, it is speculated that the resistance switching mechanism of CQD-based memristors is due to the conductive path caused by the hybridization state transition of the sp2carbon domain and sp3carbon domain induced by the reversible electric field. This avoids the drawback of uncontrollable nucleation sites leading to the random formation of conductive filaments in resistive switching. Importantly, it illustrates that the coefficient of variation (CV) of the threshold voltage can be as low as −1.551% and 0.083%, which confirms the remarkable uniform switching characteristics. Interestingly, the Pavlov's dog reflection as an important biological behavior can be demonstrated by the samples. Finally, the accuracy recognition rate of MNIST handwriting can reach up to 96.7%, which is very close to the ideal number (97.8%). A carbon-based memristor based on a new mechanism presented provides new possibilities for the improvement of brain-like computing.

Two‐dimensional layered material Ti3C2TxMXene is considered an excellent capacitive deionization (CDI) electrode material due to its two‐dimensional structure and high conductivity. However, the self‐stacking of MXene limits its structural stability and effective ion accommodation in CDI field. In this work, Ti3C2TxMXene/polypyrrole (PPy) is synthesized by in situ polymerization of conductive PPy on the surface of Ti3C2TxMXene nanosheets. The hybrid not only effectively alleviates the self‐stacking of MXene to improve the structure stability, but also combines the high conductivity of MXene and the excellent electrochemical capacity of PPy. Therefore, when used as HCDI electrode, Ti3C2TxMXene/PPy displays an excellent desalination performance including a high desalination capacity of 50.64 mg g−1, a superior desalination rate of 16.5 mg g−1min−1and excellent cycling stability. Ti3C2Tx/PPy should be a very promising electrode material for highly efficient desalination.

Solar-driven interfacial evaporation (SIE) has emerged as a promising technology owing to its enhanced heat and mass transfer characteristics when compared to conventional volumetric solar evaporation. The optimization of porous structures is recognized as a critical determinant in facilitating innovative heat and mass transfer processes within SIE systems. However, existing literature offers limited insights into the nuanced impact of distinct pore types on the efficacy of SIE functionality. In this comprehensive review, we delineate the foundational attributes of porous materials, encompassing various pore classifications, structural characteristics, and physicochemical properties. Furthermore, we provide recent advancements in the fabrication techniques of porous evaporators and investigate pivotal factors essential for optimizing SIE performance. These factors encompass strategies for augmenting light absorption efficiency, proficient heat management, effective water/steam transportation, and judicious salt elimination. Moreover, we collate seminal studies elucidating the ramifications of pore structure modifications or variations on the resultant functionality of SIE systems. The enhancement of SIE performance is conceptualized within the framework of a “structure-function-performance” paradigm. Finally, we deliberate on pertinent challenges confronting the practical implementation of porous materials in SIE applications and propose prospective avenues for further research aimed at elucidating the intricate role of porous structures in advancing SIE technology.

A hollow tubular NiCo LDH@AgNW with improved conductivity and enhanced redox kinetics for high power density Ni//Zn battery.

• A Sn-based coordination polymer with high electrical conductivity was fabricated. • The Sn-DHTPA was evaluated as an anode material for LIBs. • High capacity, ultrafast Li storage and good cycling performance were achieved. • The lithium storage mechanism was studied by a series of ex-situ characterizations. Recently, Coordination Polymers (CPs) have been widely utilized as energy storage materials for reversible Lithium-Ion Batteries (LIBs) benefiting from their tunable building blocks and adjusted electrochemical properties. However, the unsatisfied electrochemical behavior of CPs with poor conductivity and sluggish ion transport kinetics is still a bottle-neck for their large-scale energy storage applications in LIBs. Herein, we display the rational fabrication of a conductive Sn-based coordination polymer (Sn-DHTPA) via judiciously choosing suitable building units. The Sn-DHTPA is employed as anode for LIBs, exhibiting superior reversible storage capacity of 1142.6 mA h g−1 at 0.1 A g−1 after 100 cycles and impressive rate storage capability of 287.7 mA h g−1 at 20 A g−1. More importantly, a robust cycling performance of 205.5 mA h g−1 at an extra-high current density of 20 A g−1 are observed without remarkable capacity-fading up to 1000 cycles. The behavior superiority of Sn-DHTPA is related to its advanced architecture with abundant lithium storage sites, high electrical conductivity and rapid lithium transport. A series of ex-situ characterizations reveal that the impressive lithium storage capacity is contributed by the redox active sites of both the aromatic linker and metal center related to in-situ generated metallic nanoparticles dispersed in the skeleton. [Display omitted] [ABSTRACT FROM AUTHOR]

High ultraviolet (UV) stability and low dark current (I dark) are necessary for high-quality perovskite photodetectors (PDs). TiO 2 thin film is known as effective electron-transport-layer (ETL) for perovskite devices. However, common spin-coated TiO 2 ETLs endow many surface defects and have strong UV photocatalytic effect to decompose perovskite materials, resulting in inferior stability of devices. In this work, TiO 2 bilayer film (Bi-TiO 2) has been fabricated by combining spin-coating and atomic-layer-deposition process and its positive effects on UV stability and I dark of Cs 2 AgBiBr 6 -based PDs have been revealed for the first time. It is demonstrated that Bi-TiO 2 possesses fewer surface defects and smoother morphology with type Ⅱ band alignment, which is beneficial to suppress photocatalytic activity of TiO 2 and reduce carrier recombination at the interface. After accelerated strong UV aging treatment, the PD with Bi-TiO 2 maintains excellent performance, whereas the PD with spin-coated TiO 2 film dramatically deteriorate with on-off ratio drops from ∼102 to ∼2. Besides, the I dark of PD remarkably decreases from ∼10−8 A to ∼10−10 A after bilayer optimization. Furthermore, we have integrated the corresponding PDs into a self-built imaging system adopting diffuse reflection mode. This work suggests a feasible approach to fabricate TiO 2 /Cs 2 AgBiBr 6 -based PDs with remarkable UV tolerance for imaging applications. [ABSTRACT FROM AUTHOR]

Confirming the electrochemical mechanism of Na-ion storage process in expanded graphite anode and achieving a superior reversible capacity of 100 mAh g−1after 2600 cycles at 1 A g−1for Na-ion battery.

The synthesis of high-performance porous carbon materials viacarbonization of environment-friendly biomass fits perfectly with the concepts of sustainability and green chemistry. Herein, we report lignocellulose-derived porous carbon materials and their high capacitive deionization (CDI) performance, achieving a high salt adsorption capacity of 12.5 mg g-1and good cycling stability. The preparation of porous carbon materials viadirect carbonization of lignocellulose provides a number of advantages, including cost-effectiveness, high production yields, and environment-friendliness, which are ideal for industrial application of CDI. This work not only suggests novel insights to design and prepare high-performance carbon materials but also highlights the significance of green chemistry using nature-provided biomass materials to synthesize porous carbon materials.This work not only provides a new route to design and prepare high-performance carbon materials by pyrolysis of lignocellulose in a nitrogen atmosphere but also highlights the significance of green synthetic chemistry and naturally-developed biomass materials.

The exploration of new carbon materials to overcome the rapid performance decay of common carbon materials in oxygenated saline water (i.e., natural saline water) is the biggest challenge for the industrial application of the capacitive deionization (CDI) technology. In this work, we first report the layer-by-layer motif synthesis of 3D interconnected metal–organic framework (MOF) tubes and the derived nitrogen–iron-doped carbon tubes (3D-FeNC tubes) by using continuous polymeric fibers as templates. The elaborately designed 3D-FeNC tubes exhibit multiple advantages, including fast ionic diffusion (originating from the 1D hollow structure of the tubes), efficient electronic pathways and abundant active sites (arising from the 3D interconnected carbon frameworks), which are beneficial for enhancing the oxygen reduction ability. As a consequence, the as-prepared 3D-FeNC tubes exhibit an unprecedented CDI performance in oxygenated saline water with an exceptional salt adsorption capacity of 40.70 mg g−1and ultrahigh capacity retention of 93.82% even after 200 cycles, highlighting the significance of morphological control and the benefits of hollow structured materials.

Sodium-ion batteries (SIBs) often face performance limitations under stringent conditions, such as low temperatures and overcharge/overdischarge scenarios, primarily due to the inadequacies of cathode materials. Nickel hexacyanoferrate (NiHCF) has emerged as a promising candidate due to its zero-strain ion-insertion characteristic and efficient ionic diffusion pathways. However, its practical application is hindered by inadequate ionic and electronic conductivity. In this study, we address these challenges by enhancing the electronic conductivity of NiHCF through the incorporation of multi-walled carbon nanotubes (MWCNTs). This strategic integration not only leverages NiHCF’s zero-strain ion-insertion property but also significantly improves electron and ion transport. As a result, the modified NiHCF/MWCNT composite demonstrates superior electrochemical performance, exhibiting enhanced robustness and efficiency, making it suitable for large-scale energy storage applications. Under a current density of 10Ag-1at 25 ℃, the NiHCF/MWCNT composite maintains stable cycling for up to 5000 cycles, with a notable specific capacity of 59.33 mAh g-1. Even at -20 ℃, it continues to deliver robust cycling for 5000 cycles at 10Ag-1. Remarkably, after overcharging to 4.25V and overdischarging to 1.2V at both 25 ℃ and -20 ℃, the NiHCF/MWCNT electrode still maintains robust cycling performance. This advancement not only addresses the current limitations of electrode materials under extreme conditions but also offers a scalable and practical approach to improving sustainable energy storage technologies.

Metal–organic frameworks (MOFs) with high porosity and a regular porous structure have emerged as a promising electrode material for supercapacitors, but their poor electrical conductivity limits their utilization efficiency and capacitive performance. To increase the overall electrical conductivity as well as the efficiency of MOF particles, three-dimensional networked MOFs are developed via using preprepared conductive polypyrrole (PPy) tubes as the support for in situ growth of MOF particles. As a result, the highly conductive PPy tubes that run through the MOF particles not only increase the electron transfer between MOF particles and maintain the high effective porosity of the MOFs but also endow the MOFs with flexibility. Promoted by such elaborately designed MOF–PPy networks, the specific capacitance of MOF particles has been increased from 99.2 F g–1for pristine zeolitic imidazolate framework (ZIF)-67 to 597.6 F g–1for ZIF–PPy networks, indicating the importance of the design of the ZIF–PPy continuous microstructure. Furthermore, a flexible supercapacitor device based on ZIF–PPy networks shows an outstanding areal capacitance of 225.8 mF cm–2, which is far above other MOFs-based supercapacitors reported up to date, confirming the significance of in situ synthetic chemistry as well as the importance of hybrid materials on the nanoscale.

New families of materials that may potentially replace dominant carbon electrodes have emerged as a major research hotspot in the field of capacitive deionization (CDI). Here, we report a metal–organic framework (MOF)/polypyrrole (PPy) hybrid, in which conductive PPy nanotubes that are running through each MOF particle have the potential to increase the overall bulk electrical conductivity, thus promoting such a system as a good CDI electrode material. Consequently, the MOF/PPy hybrid shows a high desalination capacity of 11.34 mg g−1, which is amongst those of state-of-the-art CDI electrodes. Moreover, the MOF/PPy hybrid also shows a superior desalination performance for brackish water and good cycling stability, far exceeding typical carbon-based benchmarks. This is the first example of CDI electrodes derived from direct MOF-based materials, highlighting the potential of these hybrid systems as promising materials beyond traditional carbon electrodes.

Brackish water desalination using capacitive deionization (CDI) offers a promising solution to solve water scarcity. Activated carbons are frequently utilized as commercial electrode materials for CDI, however some limitations in their performance have prevented the practical implementation of CDI. The development of mesostructured carbons that can exceed the performance of commercial activated carbons is highly desirable. Herein, we report the first preparation of carbon nano-polyhedra with three-dimensional (3D) open highly ordered mesostructures as electrode materials for CDI. Owing to their nano-polyhedral structure with 3D open, highly ordered and well-interconnected mesochannels, the obtained mesoporous carbon materials possess large surface area for ion adsorption and shortened pathways for ion diffusion, giving rise to a high desalination capacity of 14.58 mg g−1, fast desalination rate, and stable cycling ability. More importantly, the desalination capacity of our mesoporous carbon nano-polyhedra is the highest among all mesoporous carbon-based CDI electrodes reported to date. It is believed that our mesoporous carbon nano-polyhedra would be promising for practical CDI application.

As a hole transport layer, PEDOT:PSS usually limits the stability and efficiency of perovskite solar cells (PSCs) due to its hygroscopic nature and inability to block electrons. Here, a graphene-oxide (GO)-modified PEDOT:PSS hole transport layer was fabricated by spin-coating a GO solution onto the PEDOT:PSS surface. PSCs fabricated on a GO-modified PEDOT:PSS layer exhibited a power conversion efficiency (PCE) of 15.34%, which is higher than 11.90% of PSCs with the PEDOT:PSS layer. Furthermore, the stability of the PSCs was significantly improved, with the PCE remaining at 83.5% of the initial PCE values after aging for 39 days in air. The hygroscopic PSS material at the PEDOT:PSS surface was partly removed during spin-coating with the GO solution, which improves the moisture resistance and decreases the contact barrier between the hole transport layer and perovskite layer. The scattered distribution of the GO at the PEDOT:PSS surface exhibits superior wettability, which helps to form a high-quality perovskite layer with better crystallinity and fewer pin holes. Furthermore, the hole extraction selectivity of the GO further inhibits the carrier recombination at the interface between the perovskite and PEDOT:PSS layers. Therefore, the cooperative interactions of these factors greatly improve the light absorption of the perovskite layer, the carrier transport and collection abilities of the PSCs, and especially the stability of the cells.

A high-quality perovskite film with interconnected perovskite grains was obtained by incorporating terephthalic acid (TPA) additive into the perovskite precursor solution. The presence of TPA changed the crystallization kinetics of the perovskite film and promoted lateral growth of grains in the vicinity of crystal boundaries. As a result, sheet-shaped perovskite was formed and covered onto the bottom grains, which made some adjacent grains partly merge together to form grains-interconnected perovskite film. Perovskite solar cells (PSCs) with TPA additive exhibited a power conversion efficiency (PCE) of 18.51% with less hysteresis, which is obviously higher than that of pristine cells (15.53%). PSCs without and with TPA additive retain 18 and 51% of the initial PCE value, respectively, aging for 35 days exposed to relative humidity 30% in air without encapsulation. Furthermore, MAPbI3film with TPA additive shows superior thermal stability to the pristine one under 100 °C baking. The results indicate that the presence of TPA in perovskite film can greatly improve the performance of PSCs as well as their moisture resistance and thermal stability.

Currently sodium-ion batteries (SIBs) as energy storage technology have attracted lots of interest due to their safe, cost-effective, and nonpoisonous advantages. However, many challenges remain for development of SIBs with high specific capacity, high rate capability, and long cycle life. Therefore, CuS as an important earth-abundant, low-cost semiconductor was applied as anode of SIBs with ether-based electrolyte instead of conventional ester-based electrolyte. By incorporating reduced graphene oxide (RGO) into CuS nanosheets and optimizing the cutoff voltage, it is found that the sodium-ion storage performance can be greatly enhanced using ether-based electrolyte. The CuS-RGO composites deliver an initial Coulombic efficiency of 94% and a maximum specific capacity of 392.9 mAh g–1after 50 cycles at a current density of 100 mA g–1. And a specific capacity of 345 mAh g–1is kept after 450 cycles at a current density of 1 A g–1. Such an excellent electrochemical performance is ascribed to the conductive network construction of CuS-RGO composites, the suppression of dissolved polysulfide intermediates by using ether-based electrolyte, and the avoidance of conversion-type reaction by optimizing the cutoff voltage.

The performance characteristics of polymer solar cells (PSCs) incorporated with AgAl and Ag nanostructures and MoO3spacer layers were investigated. The power conversion efficiency (PCE) of PSCs is sensitive to the nominal thicknesses of the AgAl nanostructures and the MoO3spacer layer. The PCE of a PSC with a 3-nm-thick layer of AgAl nanostructures and a 1-nm-thick MoO3isolation layer reached 9.79%, which is higher than the PCE (8.55%) of the reference PSC without metal nanostructures. Compared to PSCs with Ag nanostructures, PSCs with AgAl nanostructures showed better stability and still retained 60% of their initial PCE values after aging for 120 days in air without encapsulation. The enhanced stability of the PSCs is attributed to the formation of AlOx, which can inhibit the diffusion of Ag atoms into the neighboring layer. The localized surface plasmonic resonance (LSPR) effect of AgAl nanostructures was retained by inserting an only 1-nm-thick MoO3spacer layer between the metal nanostructures and the metal electrode. Our work has demonstrated that using AgAl alloy instead of Ag as plasmonic nanostructures is a better strategy for improving the performance of PSCs, especially in terms of the stability of the cells.

This article reports a systematic study of how Au atoms nucleate and grow on Pd icosahedral seeds with a multiply twinned structure. By manipulating the reduction kinetics, we obtained Pd–Au bimetallic nanocrystals with two distinct shapes and structures. Specifically, Pd@Au core–shell icosahedra were formed when a relatively fast reduction rate was used for the HAuCl4precursor. At a slow reduction rate, in contrast, the nucleation and growth of Au atoms were mainly confined to one of the vertices of a Pd icosahedral seed, resulting in the formation of a Au icosahedron by sharing five adjacent faces with the Pd seed. The same growth pattern was observed for Pd icosahedral seeds with both sizes of 32 and 20 nm. We have also investigated the effects of other kinetic parameters, including the concentration of reducing agent and reaction temperature, on the growth pathway undertaken by the Au atoms. We believe that the mechanistic insights obtained from this study can be extended to other systems, including the involvement of different metals and/or seeds with different morphologies.

The BIEF and “ion reservoir” at the heterogeneous interface, combining with the crosslinking pathways, enables the desired WS2/Ti3C2Txheterojunction with robust reaction kinetics and excellent sodium storage performance at both room and low temperatures.

The performance and air stability of inverted polymer solar cells (PSCs) were greatly improved using a combination of LiF-modified ITO cathode and a MoO3/AgAl alloy anode. The power conversion efficiency (PCE) of PSCs with AgAl contact reached 9.4%, which is higher than that of the cells with Ag (8.8%) and Al electrode (7.6%). The PCE of AgAl-based PSCs can further increase up to 10.3% through incorporating an ultrathin LiF-modified ITO. AgAl-based cells also exhibit a superior stability compared to the cells with Ag and Al contacts. PCE of the AgAl-based cells without encapsulation remains 78% of its original value after the cells were aged for 380 days in air. The presence of a LiF-modified ZnO interlayer between ITO and the organic active layer improves the charge collection. The improvement in PCE and stability of the AgAl-based cells is primarily attributed to the formation of AlOxat the MoO3/AgAl interface, preventing Ag diffusion and improving the built-in potential across the active layer in the cells.

Semiconductor photocatalysis has attracted tremendous attention due to its potential in environmental remediation, clean energy production and chemical reaction technology. Pursuing high efficiencies is a core task in the field. One of the major factors in photocatalysis is the limited light absorption of photocatalysts in the incident solar spectrum. In this treatise, we will survey recent advancements in light-conversion phosphor-based composites including up-conversion, down-conversion, and long afterglow phosphor-based composites for photocatalysis.

The carbon nanotube and carbon nanofibre (CNT–CNF) composite films are synthesized on different graphite substrate by low-pressure and low-temperature chemical vapor deposition. Scanning electron microscopy measurement and N2adsorption experiment show that CNT–CNF composite films have network structure with optimal pore size distribution, which is beneficial to capacitive deionization. Atomic force microscopy result indicates that there is a strong correlation between the surface roughness of graphite and their thickness. Furthermore, the electrosorptive performance in salt solutions by employing as-grown CNT–CNF composite film is studied and found that the properties of the graphite substrate play a vital role in electrosorptive performance of CNT–CNF composite films by influencing their network structures.

TiO2at the nanoscale perform well in the UV photocatalytic application depending on the particle size; a combination of TiO2and Au may improve the situation. TiO2–Au composites are thus synthesized and examined in the UV photocatalytic reduction of Cr(VI). Results show that the photocatalytic efficiency of TiO2–Au reaches 91% in Cr(VI) reduction compared with the pure TiO2(83%) under UV light irradiation. The increased light absorption intensity in a broader spectral range as well as the rate of electron-hole pair recombination in TiO2with the addition of Au shall be responsible for the enhanced photocatalytic ability of the composite.

AbstractThe carbon nanotube and carbon nanofibre (CNT–CNF) composite films are synthesized on different graphite substrate by low-pressure and low-temperature chemical vapor deposition. Scanning electron microscopy measurement and N2adsorption experiment show that CNT–CNF composite films have network structure with optimal pore size distribution, which is beneficial to capacitive deionization. Atomic force microscopy result indicates that there is a strong correlation between the surface roughness of graphite and their thickness. Furthermore, the electrosorptive performance in salt solutions by employing as-grown CNT–CNF composite film is studied and found that the properties of the graphite substrate play a vital role in electrosorptive performance of CNT–CNF composite films by influencing their network structures.

ABSTRACTTiO2at the nanoscale perform well in the UV photocatalytic application depending on the particle size; a combination of TiO2and Au may improve the situation. TiO2–Au composites are thus synthesized and examined in the UV photocatalytic reduction of Cr(VI). Results show that the photocatalytic efficiency of TiO2–Au reaches 91% in Cr(VI) reduction compared with the pure TiO2(83%) under UV light irradiation. The increased light absorption intensity in a broader spectral range as well as the rate of electron-hole pair recombination in TiO2with the addition of Au shall be responsible for the enhanced photocatalytic ability of the composite.

SnO2quantum dots (QDs) were successfully synthesized viaa microwave-assisted reaction of a SnO2precursor in an aqueous solution using a microwave system. The morphology, structure and photocatalytic performance in the degradation of methylene blue (MB) were characterized by scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction spectroscopy, UV-vis absorption/reflectance spectroscopy and electrochemical impedance spectroscopy, respectively. The results show that the SnO2QDs synthesized at a pH value of 5 exhibit an optimal photocatalytic performance with a MB degradation rate of 90% at 240 min under visible light irradiation due to their easier adsorption of pollutants, higher visible light absorption and lower electron–hole pair recombination.

AbstractMembrane capacitive deionization (MCDI) is a promising technology for desalination with the potential of lowering energy consumption and treatment cost. In this paper, batch mode experiments were carried out to evaluate the charge efficiency of the MCDI process. Specifically, charge efficiency is a very functional tool to examine the double layer structure inside of porous electrode. The results show that the charge efficiency in MCDI is a function of both cell voltage and solution conductivity. Specifically, it was found that the charge efficiency was proportional to cell voltage while inversely to solution conductivity. The maximum charge efficiency (0.55) in MCDI was far less than one, indicating the high transient resistivity between membrane and carbon electrodes.

AbstractZnO sheets have been synthesized via microwave-assisted reaction of ZnO precursor in aqueous solution using a CEM microwave system. Their morphologies, crystal structures and photocatalytic performances in the reduction of Cr(VI) were characterized using scanning electron microscopy, transmission electron microscopy, X-ray diffraction spectroscopy and UV-vis absorption spectrophotometer, respectively. Results show that ZnO sheets synthesized in 5 min time scale exhibits a optimal photocatalytic performance in the reduction of Cr(VI) with removal efficiency of 81% under UV irradiation due to the maximal intensity of light absorption and the minimal probability of electron-hole pair recombination.

ZnO sheets have been synthesized via microwave-assisted reaction of ZnO precursor in aqueous solution using a CEM microwave system. Their morphologies, crystal structures and photocatalytic performances in the reduction of Cr(VI) were characterized using scanning electron microscopy, transmission electron microscopy, X-ray diffraction spectroscopy and UV-vis absorption spectrophotometer, respectively. Results show that ZnO sheets synthesized in 5 min time scale exhibits a optimal photocatalytic performance in the reduction of Cr(VI) with removal efficiency of 81% under UV irradiation due to the maximal intensity of light absorption and the minimal probability of electron-hole pair recombination.

Membrane capacitive deionization (MCDI) is a promising technology for desalination with the potential of lowering energy consumption and treatment cost. In this paper, batch mode experiments were carried out to evaluate the charge efficiency of the MCDI process. Specifically, charge efficiency is a very functional tool to examine the double layer structure inside of porous electrode. The results show that the charge efficiency in MCDI is a function of both cell voltage and solution conductivity. Specifically, it was found that the charge efficiency was proportional to cell voltage while inversely to solution conductivity. The maximum charge efficiency (0.55) in MCDI was far less than one, indicating the high transient resistivity between membrane and carbon electrodes.

ZnO–reduced graphene oxide (RGO)–carbon nanotube (CNT) composites were successfully synthesized viamicrowave-assisted reduction of a graphite oxide dispersion in zinc nitrate solution with a CNT suspension. Their photocatalytic performance in the degradation of methylene blue was investigated and the results show that the CNTs play an important role in the enhancement of the photocatalytic performance and the ZnO–RGO–CNT composite with 3.9 wt% CNTs achieves a maximum degradation efficiency of 96% under UV light irradiation for 260 min as compared with ZnO–RGO (88%) due to the increased light absorption and the reduced charge recombination with the introduction of CNTs.

Graphene was synthesized by the modified Hummers method and a hydrazine reduction process. The obtained graphene was characterized by various diagnostic techniques, such as scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). A layer of transparency crumpled film was obtained with an interlayer spacing of 0.37 nm. The two typical peaks of 3415 and 1091 cm−1correlated to OH and CO were observed from the FTIR spectrum. The samples showed an enhanced thermal stability promoting the way for the research and the applications of graphene.

A CdS/CdSe quantum-dot (QD)-cosensitized TiO2film has been fabricated using a microwave-assisted chemical bath deposition technique and used as a photoanode for QD-sensitized solar cells. The technique allows a direct and rapid deposition of QDs and forms a good contact between QDs and TiO2films. The photovoltaic performance of the as-prepared cell is investigated. The results show that the performance of the CdS/CdSe-cosensitized cell achieves a short-circuit current density of 16.1 mA cm–2and a power conversion efficiency of 3.06% at one sun (AM 1.5 G, 100 mW cm–2), which is comparable to the one fabricated using conventional successive ionic layer adsorption and reaction technique.

A membrane capacitive deionization (MCDI) device, which combines ion-exchange membranes and carbon nanotube and carbon nanofiber (CNT-CNF) film electrodes, has been developed to investigate the selective electrosorption of different cations and anions. The CNT-CNF films are synthesized by low pressure and low temperature thermal chemical vapor deposition. The experimental results show that multivalent cations and anions are better adsorbed from aqueous solution and for cations or anions with same charge, the one with smaller hydrated radius will be more effectively removed.

A membrane capacitive deionization (MCDI) device, which combines ion-exchange membranes and carbon nanotube and carbon nanofiber (CNT-CNF) film electrodes, has been developed to investigate the selective electrosorption of different cations and anions. The CNT-CNF films are synthesized by low pressure and low temperature thermal chemical vapor deposition. The experimental results show that multivalent cations and anions are better adsorbed from aqueous solution and for cations or anions with same charge, the one with smaller hydrated radius will be more effectively removed.

Sensitized-type solar cells based on TiO2photoanodes and CdS quantum dots (QDs) as sensitizers have been studied. CdS QDs are grown on TiO2films, utilizing one-step microwave assisted chemical bath deposition (MACBD) method. This method allows a facile and rapid deposition and integration between CdS QDs and TiO2films. The photovoltaic performances of the cells fabricated using CdS precursor solutions with different concentrations are investigated. The results show that the cell based on MACBD deposited TiO2/CdS electrode achieves a maximum short circuit current density of 7.20 mAcm-2and power conversion efficiency of 1.18 % at one sun (AM 1.5G, 100 mW cm-2), which is comparable to the ones prepared using conventional techniques.

Abstract

The extremely high catalytic efficiency of undercoordinated noble metal adatoms is indeed fascinating, but its chemical and electronic origin remains yet puzzling. Incorporating the BOLS correlation theory [Sun, C. Q. Prog. Solid State Chem.2007, 35, 1] into the high-resolution XPS measurements [Baraldi, A.; et al. New J. Phys. 2007, 9, 143; Bianchettin, L.; et al. J. Chem. Phys.2008, 128, 114706] has affirmed the BOLS expectations that the broken bonds induce local strain and quantum trapping in addition to polarization of the otherwise conductive half-filled s-shell charge by the tightly- and densely-trapped inner electrons of the adatoms. Both the trapped and polarized states would be detectable from the density-of-states evolution of the valence and the core bands. The trapped states have been discovered at the bottom edges of Pt(5d106s0) 4f7/2and Rh 3d5/2bands, and the polarized states only present at the upper edge of Rh(4d85s1) 3d5/2. It is suggested that the quantum trapping increases the electroaffinity and the polarization does oppositely. Therefore, the Rh adatom serves as a donor and the Pt adatom as an acceptor in the process of catalytic reaction.