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We report a facile approach to construct Co@NiFe-LDH heterostructure catalyst with superior OER and Zn–air performance. DFT calculations revealed that Fe site is the OER active center, while forming heterostructure upshifts the Fe d-band center.

With the rapid development of economy, the past decades have experienced more and more severe energy depletion and environmental pollution issues, hence it is urgent to develop more environmental-friendly energy devices, such as fuel cells, metal-air batteries, water electrolysis and so on. However, such devices have long been suffering from the sluggish reaction kinetics and high energy barriers, plus the conventional electrocatalysts used in these devices mostly are noble-metal-based materials, such as Pt/C, IrO2, and RuO2. These noble-metal-based electrocatalysts possess significant disadvantages such as high price, limited reserves, and undesirable stability, and these factors together hinder their large-scale industrial application and the inhomogeneity of the catalyst structure at the atomic level also impose great challenges to disclose the underlying catalytic mechanism. Noble metal nanoclusters, as a promising type of electrocatalyst with definitive composition and structure, have been attracting increasingly research efforts. This review aims to summarize the recent achievements of molecular metal nanoclusters employed in electrocatalytic processes, with particular elaboration on oxygen reduction reaction (ORR), hydrogen evolution reaction (HER), oxygen evolution reaction (OER), as well as to unravel the catalytic mechanism and establish the relationship between its structure and functionality. Specifically, the size effect, the metal core configuration, charge effect, size effect, ligand effect, and metal-ligand binding motifs of the metal clusters that would impact the electrocatalytic performance are comprehensively discussed. In the end, the outlook and perspective including challenges and opportunities are proposed. We anticipate this review would be beneficial for gaining a deeper understanding of engineering nanoclusters for electrocatalysis and to expand its application in electrocatalysis.

Although CRISPR/Cas9-mediated gene editing is widely applied to mimic human disorders, whether acute manipulation of disease-causing genes in the brain leads to behavioral abnormalities in non-human primates remains to be determined. Here we induced genetic mutations in MECP2, a critical gene linked to Rett syndrome (RTT) and autism spectrum disorders (ASD), in the hippocampus (DG and CA1–4) of adolescent rhesus monkeys (Macaca mulatta) in vivo via adeno-associated virus (AAV)-delivered Staphylococcus aureus Cas9 with small guide RNAs (sgRNAs) targeting MECP2. In comparison to monkeys injected with AAV-SaCas9 alone (n = 4), numerous autistic-like behavioral abnormalities were identified in the AAV-SaCas9-sgMECP2-injected monkeys (n = 7), including social interaction deficits, abnormal sleep patterns, insensitivity to aversive stimuli, abnormal hand motions, and defective social reward behaviors. Furthermore, some aspects of ASD and RTT, such as stereotypic behaviors, did not appear in the MECP2 gene-edited monkeys, suggesting that different brain areas likely contribute to distinct ASD symptoms. This study showed that acute manipulation of disease-causing genes via in vivo gene editing directly led to behavioral changes in adolescent primates, paving the way for the rapid generation of genetically engineered non-human primate models for neurobiological studies and therapeutic development.

Shape-memory biomaterials, especially those stable against degradation, are attractive for applications in the biomedical fields, such as artificial bone scaffold material, artificial blood vessel ...

Developing high-performance catalysts for oxygen evolution reaction (OER) is critical for the widespread applications of clean and sustainable energy through electrochemical devices such as zinc-air batteries and (photo)electrochemical water splitting. Constructing heterostructure and oxygen vacancies have demonstrated great promises to boost the OER performance. Herein, we report a facile strategy to fabricate hetero-structured NiFe2 O4 /Ni3 S4 nanorods, where NiFe2 O4 can be derived from Fe-based metal-organic frameworks (MOFs). The NiFe2 O4 /Ni3 S4 catalyst exhibited excellent OER performance, evidenced by an overpotential value of 357 mV at the current density of 20 mA cm-2 , and a small Tafel slope of 87.46 mV dec-1 in 1 M KOH, superior to the benchmark IrO2 catalyst. Moreover, NiFe2 O4 /Ni3 S4 outperformed with regard to long-term durability for OER than IrO2 . Such outstanding OER performance is mainly accounted by the interface between NiFe2 O4 and Ni3 S4 , and the presence of rich oxygen vacancies. When employed as air-cathode in zinc-air batteries, the NiFe2 O4 /Ni3 S4 decorated battery had a high round-trip efficiency of 62.1% at 10 h, and possessed long-term stability of >50 h. This study may pave the way for fabricating non-noble-metal-based cost-effective, efficient and durable electrocatalysts for OER, zinc-air batteries, and beyond.

Bi2S3 is a n-type (negative type) semiconductor that has a narrow band gap and an ideal band edge position for hydrogen generation. However, high charge recombination rate, low photoelectrochemical (PEC) efficiency and poor stability are of major concerns of Bi2S3 as a photoelectrode. Herein, we report an efficient Vanadium-rich Bi2S3 nanowires (atomic ratio of V to Bi is 1/22) that have been prepared on fluorine-doped tin oxide (FTO) substrate by an in-situ solution-processed reaction with BiVO4 film as precursor. The resulting V-rich photoelectrode demonstrates notably high charge separation efficiency and fast charge transport with respect to pristine Bi2S3 nanowires. As a result, the photocurrent density of ca. 10 mA·cm−2 at -0.2 V vs Ag/AgCl is obtained under visible light illumination. In addition, V-rich Bi2S3 generates IPCE (incident photocurrent-to-current conversion efficiency) of 50% at 460 nm and 45% at 760 nm, demonstrating a 2.0 and 2.8-fold increase, respectively, when compared with pristine Bi2S3. This enhancement is probably due to increased light absorption, less charge recombination, and faster charge transfer. More importantly, in contrast to pristine Bi2S3 sample that suffers detrimental photocorrosion in sulfide containing electrolyte, V-rich Bi2S3 nanowires retain 84.6% of its initial photocurrent over the course of 1 h. These findings are expected to shed light on engineering high-performance and robust metal sulfide materials for photoelectrochemical application.

Binary transition metal selenides have been more promising than single transition metal selenides as anode materials for sodium-ion batteries (SIBs). However, the controlled synthesis of transition metal selenides, especially those derived from metal-organic-frameworks with well-controlled structure and morphology is still challenging. In this paper, highly porous NiCoSe4 @NC composite microspheres were synthesized by simultaneous carbonization and selenization of a Ni-Co-based metal-organic framework (NiCo-MOF) and characterized by scanning electron microscopy, transition electron microscopy, X-Ray diffraction, X-Ray photoelectron spectroscopy and electrochemical techniques. The rationally engineered NiCoSe4 @NC composite exhibits a capacity of 325 mAh g-1 at a current density of 1 A g-1 , and 277.8 mAh g-1 at 10 A g-1 . Most importantly, the NiCoSe4 @NC retains a capacity of 293 mAh g-1 at 1 A g-1 after 1500 cycles, with a capacity decay rate of 0.025 % per cycle.

We report an efficient and environment-friendly method of synthesizing biodegradable, shape memory polyurethanes via a catalyst-free polymerization process. Two different polyurethanes (poly(PCL-1,4-butanediol-urethane) PCBU and poly(PCL-5,5′,6,6′-tetrahydroxy-3,3,3′,3′-tetramethyl-1,1′-spirobisindane-urethane) PCTU) were composed by the soft segment of polycaprolactone diol and the hard segment of non-planar ring structure/hexamethylene diisocyanate. The polyurethane products obtained were confirmed by FTIR spectroscopy and Atomic Force Microscopy (AFM). PCTU and PCBU exhibited a shape fixation rate of 99.3% and 91.1% and shape recovery rate of 98.3% and 85.1%, respectively during a triple-shape memory procedure. Notably, these PUs had superior biodegradability in buffer solution without enzyme catalysis and the biodegradation weight loss ratio of the PCBU reached 48% within 3 months in the buffer solution.

Increasing the voltage window of an electrode material is effective for improving the energy density of aqueous symmetric supercapacitors. Herein, a novel aqueous symmetric supercapacitor equipped with a high cell voltage window of 2.6 V was assembled by P-doped TiO2 nanotube arrays on a Ti sheet. The arrays exhibit a wide potential range of about 1.2 V as the cathode, and a stable wide potential range of 1.4 V as the anode was also obtained. These wide potential windows in the cathode and anode render the symmetric supercapacitor with a very large working voltage window reaching 2.6 V, and thus a high volumetric energy density (1.65 mW h cm−3). These results suggest that P-doped TiO2 nanotube arrays can be promising candidates for energy storage devices.

Solar energy-driven interfacial water evaporation is a promising energy utilization technology in the field of seawater desalination and water purification. However, the accumulation of salt on the heating surface severely impairs the water evaporation performance and long-time stability. Herein, we demonstrate a new kind of photothermal paper comprising a high-temperature-resistant paper made from ultralong hydroxyapatite nanowires and glass fibers and black nickel oxide (NiO) nanoparticles for solar energy-driven desalination. Owing to the high photothermal conversion ability, fast water transportation in the air-laid paper, and good heat insulation, the hydrophilic HN/NiO photothermal paper can achieve efficient, stable and recyclable water evaporation performance. In addition, a Janus HN/NiO photothermal paper based on hydrophobic sodium oleate-modified ultralong hydroxyapatite nanowires has been developed, and it has a high water evaporation efficiency of 83.5% under 1 kW m-2 irradiation. In particular, with the bottom hydrophobic ultralong hydroxyapatite nanowire layer and water-transporting channels in the air-laid paper to facilitate salt exchange, the as-prepared Janus evaporator exhibits no salt accumulation on the surface, high performance and long-time stable desalination using simulated seawater (3.5 wt% NaCl). Furthermore, the Janus evaporator with the hydrophobic ultralong hydroxyapatite nanowire substrate can be extended to support other photothermal materials such as black titanium oxide (Ti2O3) and Ketjen black carbon. The as-prepared Janus HN/Ti2O3 and Janus HN/KB photothermal paper also exhibit salt-resistant desalination function. The as-prepared Janus salt-resistant photothermal paper with efficient, stable and recyclable merits has great potential in solar energy-driven desalination and water purification.

High-efficiency recoverable catalytic magnetite microgel particles, comprising a magnetic Fe3O4 nanoparticle (NP) core with a thermo-sensitive poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) polymer shell, were synthesized through a four-step procedure. The preparation route involved the following steps: (1) preparation of Fe3O4 NPs through a hydrothermal method; (2) attachment of double-bond functionalization to the surface of the NPs; (3) self-initiated photo-grafting and photopolymerization (SIPGP) of a monomer of 2-(dimethylamino) ethyl methacrylate (DMAEMA); (4) anchoring of Au onto Fe3O4@PDMAEMA magnetic microgel particles. Perfect surface functionalization was characterized by dynamic light scattering (DLS), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), and transmission electron microscopy (TEM). The Fe3O4@PDMAEMA–Au microgel particles exhibited excellent thermally adjustable catalytic activity for the typical reduction of 4-nitrophenol (4-NP). In addition, the Fe3O4@PDMAEMA–Au catalyst was responsive to an external magnetic field, allowing the microgel particles to be easily separated and recovered from water after the catalytic reaction. This type of novel smart microgel nanocatalyst has the potential to be applied as a high-performance, sustainable, catalytic system in the field of chemical synthesis, micromotors, and bio-molecule immobilization.

The direct transformation of external energy into mechanical work by the self-propelled motor inspires and promotes the development of miniaturized machines. Several strategies have been utilized to realize the self-driven motion, but in some cases multiple power sources are needed, and this would complicate the operation in diverse environments. In this regard, the dual-mode self-propelled system based on a single power source is highly desirable. In this work, single-light-actuated dual-mode propulsion at the liquid/air interface is realized by using flexible, superhydrophobic, and thermostable photothermal paper made from flexible ultralong hydroxyapatite nanowires, titanium sesquioxide (Ti2O3) particles, and poly(dimethylsiloxane) coating. The superhydrophobic surface enables the thermostable photothermal paper to float on the water surface spontaneously and significantly reduces the drag force. In the usual situation, the heat power produced by the photothermal effect is utilized to trigger the Marangoni propulsion. While the Marangoni effect is quenched in water containing the surfactant, the propulsion mode can be directly switched into the vapor-enabled propulsion mode by simply increasing the light power density. Particularly, the light-driven motion in a linear, curvilinear, or rotational manner can be realized by designing the self-propelled machines with appropriate shapes by using the processable photothermal paper. It is expected that the as-prepared dual-mode self-propelled, flexible, superhydrophobic, and thermostable photothermal paper-based devices have promising applications in various fields such as microrobots, biomedicine, and environmental monitoring.

Oxygen vacancy engineering is effective for improving the photoelectrochemical (PEC) performance of electrodes. However, such a protocol has not yet shown impressive success for ZnO photoanodes due...

Solar energy-driven water evaporation is a promising technique for clean water regeneration to tackle the world-wide water scarcity problem. Previous studies have revealed the important role of the bilayer structure in the solar energy-driven water evaporation, the top layer is the photothermal material, and the bottom porous material is used for water transportation and heat insulation. Herein, a new kind of the bilayer aerogel composed of hydrophilic ultralong hydroxyapatite (HAP) nanowire aergel and hydrophobic carbon nanotube (CNT) coating has been developed and demonstrated as a highly efficient self-floating evaporator for solar energy-driven photothermal water purification. The hydrophilic and highly porous HAP nanowire aerogel with a low thermal conductivity ensures excellent thermal management and high water evaporation rate, and the CNT coating layer enables highly efficient solar light absorption and energy conversion. With these structural merits, the as-prepared HAP/CNT bilayer aerogel has a high water evaporation rate of 1.34 kg m−2 h−1 and high water evaporation efficiency of 89.4% under solar light irradiation at a power density of 1 kW m−2. Additionally, the high-performance water purification function of the HAP/CNT bilayer aerogel is demonstrated by producing clean water from the actual seawater and simulated wastewater. The experimental results demonstrate the promising potential of the as-prepared HAP/CNT bilayer aerogel for high-performance solar energy-driven photothermal clean water regeneration.

Information protection is particularly important for secure communication between parties, avoiding the leakage of secret information to unknown parties. Among various strategies used for information protection in the previous reports in the literature, security inks made from photoluminescent materials are the most widely investigated. The security inks suffer from the drawbacks such as lack of universality on various substrates. In this work, we provide a promising new complement to the security ink-based protection techniques. We report a kind of portable photoluminescent chalk made from lanthanide-doped ultralong hydroxyapatite nanowires, which can directly write the covert information at anytime and anyplace on arbitrary surfaces and substrates including paper sheets, metals, fabrics, plastics, woods, walls, foams, leaves, and even human body. The as-written original information cannot be recognized under the ambient light, but it is readable upon exposure to the ultraviolet light. In this work, the dual and triple encryption strategies are also provided for the high-level information protection. It is expected that the versatile, convenient, and user-friendly strategy demonstrated herein is promising for the on-site secret information protection.

Security inks based on photoluminescent materials are mostly investigated for security applications, such as information encryption and decryption, anti-counterfeiting, and data storage. Although they are invisible to the naked eye under ambient light, they can be detected under ultraviolet or near-infrared light. Herein, a new kind of secret paper made from network-structured ultralong hydroxyapatite nanowires and cellulose fibers has been developed. White vinegar, a common cooking ingredient, is used as an invisible security ink. Covert information on the secret paper written with white vinegar is totally invisible under natural light, but it can be decrypted and clearly read after exposure to fire; the response time to fire is short (

Stimulus-responsive actuators that can respond to the external stimuli and convert external energy into dynamic movement behaviors are highly desired for many applications. Among various driving sc...

A dinuclear cobalt-based pillar-layered-like metal–organic frameworks (MOFs), namely [Co2(TPPA)(sdba)2]n (1) has been synthesized hydrothermally (TPPA = tris(4-(pyridin-4-yl)phenyl)amine, H2sdba = 4,4′-sulfonyldibenzoic acid). MOF 1 features a two-fold interpenetrated CdSO4-type (cds) network. MOF 1 can be used as an electrode material for supercapacitors, the maximum specific capacitance is 75.7 F g−1 at current density 0.5 A g−1, while the maximum specific capacitance of the Co3O4 material with sheet-like nanoporous structure by calcination of 1 at 500 °C achieved 118.6 F g−1 at current density of 0.5 A g−1. The above two materials have excellent recycling stability, their capacitance retention can be kept at 94% and 97% after 3000 cycles at 1 A g−1 in 3 M KOH electrolyte, respectively. In addition, MOF 1 also displays photocatalytic activity for the decomposition of RhB under UV irradiation, approximately 94% of RhB was decomposed after 60 min.

Graphitic carbon nitride (g-C3 N4 ) has been widely explored as a photocatalyst for water splitting. The anodic water oxidation reaction (WOR) remains a major obstacle for such processes, with issues such as low surface area of g-C3 N4 , poor light absorption, and low charge-transfer efficiency. In this work, such longtime concerns have been partially addressed with band gap and surface engineering of nanostructured graphitic carbon nitride (g-C3 N4 ). Specifically, surface area and charge-transfer efficiency are significantly enhanced through architecting g-C3 N4 on nanorod TiO2 to avoid aggregation of layered g-C3 N4 . Moreover, a simple phosphide gas treatment of TiO2 /g-C3 N4 configuration not only narrows the band gap of g-C3 N4 by 0.57 eV shifting it into visible range but also generates in situ a metal phosphide (M=Fe, Cu) water oxidation cocatalyst. This TiO2 /g-C3 N4 /FeP configuration significantly improves charge separation and transfer capability. As a result, our non-noble-metal photoelectrochemical system yields outstanding visible light (>420 nm) photocurrent: approximately 0.3 mA cm-2 at 1.23 V and 1.1 mA cm-2 at 2.0 V versus RHE, which is the highest for a g-C3 N4 -based photoanode. It is expected that the TiO2 /g-C3 N4 /FeP configuration synthesized by a simple phosphide gas treatment will provide new insight for producing robust g-C3 N4 for water oxidation.

Two Zn2+-based luminescent metal–organic frameworks containing the same components, {[Zn(TIPA)pim0.5]2H2O·NO3}n (1) and {[Zn(TIPA)(pim)]3H2O}n (2) have been synthesized based on a π-electron rich semi-rigid triangular ligand TIPA (TIPA = tris(4-(1H-imidazol-1-yl)-phenyl)amine and H2pim = pimelic acid). 1 is a two-fold interpenetrating 3D framework containing four chiral (10,3)-a subnets, and 2 is merely a 2D + 2D → 2D entangled network, although they were synthesized from the same starting materials. A photoluminescence investigation revealed that the emissions of 1 and 2 entirely originate from the intraligands charge transfer transitions (π → π*). Metal–organic framework 1 can be applied as a dual functional chemical sensor for nitroaromatic (NAC) compounds and antibiotics detection with a high sensitivity and quick response. In addition, the effective detection of nitroaromatic compounds and antibiotics was rationalized by the density functional theory (DFT) calculation of the energy bands of the NAC compounds and antibiotics, which revealed that a photoinduced electron transfer mechanism is largely responsible for the sensing of nitroaromatic compounds, and the resonance energy transfer is largely responsible for the exclusive sensing of ofloxacin (OFX).

Tubular hematite with high-concentration, uniform doping is regarded as a promising material for photoelectrochemical water oxidation. However, the high-temperature annealing commonly used for activating doped hematite inevitably causes deformation of the tubular structure and an increase in the trap states. In the present work, Sn-doped tubular hematite on fluorine-doped tin oxide (FTO) is successfully obtained at 750 °C from a Sn-coated FeOOH tube precursor. Sn/P codoping, which is rarely considered for hematite, is also achieved via a gas phase reaction in phosphide atmosphere. The tubular morphology allows the dopant to diffuse from both the inner and outer surfaces, thus decreasing the doping profile in the radial direction. The even distribution of Sn and P synergetically increases the carrier density of hematite by one order of magnitude, which shortens the width of the depletion layer to ca. 2.3 nm (compared with 19.3 nm for the pristine sample) and leads to prolonged carrier lifetime and efficient charge separation. In addition, this codoping protocol does not introduce additional surface trap states, as evidenced by the increased charge injection efficiency and surface kinetic analysis using intensity modulated photocurrent spectroscopy (IMPS). As a result, the morphology- and doping-engineered hematite exhibits photocurrents of 0.9 mA cm-2 at 1.23 V and 3.8 mA cm-2 at 2.0 V vs. RHE under AM 1.5 G illumination (100 mW cm-2) in 1.0 M NaOH, representing 4.5-fold and 4.8-fold enhancements, respectively, compared with the photocurrents of undoped hematite. The present method is shown to be effective for preparing multi-element-doped hematite nanotubes and may find broad application in the development of other nanotubular photoelectrodes with or without doping for efficient and robust water oxidation.

Poor charge separation is the main factor that limits the photocatalytic hydrogen generation efficiency of organic conjugated polymers. In this work, a series of linear donor–acceptor (D–A) type oligomers are synthesized by a palladium-catalyzed Sonogashira–Hagihara coupling of electron-deficient diborane unit and different dihalide substitution sulfur functionalized monomers. Such diborane-based A unit exerts great impact on the resulting oligomers, including distinct semiconductor characters with isolated lowest unoccupied molecular orbital (LUMO) orbits locating in diborane-containing fragment, and elevated LUMO level higher than water reduction potential. Relative to A-A type counterpart, the enhanced dipole polarization effect in D–A oligomers facilitates separation of photogenerated charge carriers, as evidenced by notably prolonged electron lifetime. Owing to π–π stacking of rigid backbone, the oligomers can aggregate into an interesting 2D semicrystalline nanosheet (≈2.74 nm), which is rarely reported in linear polymeric photocatalysts prepared by similar carbon–carbon coupling reaction. Despite low surface area (30.3 m2 g−1), such ultrathin nanosheet D–A oligomer offers outstanding visible light (λ > 420 nm) hydrogen evolution rate of 833 µmol g−1 h−1, 14 times greater than its A-A analogue (61 µmol g−1 h−1). The study highlights the great potential of using boron element to construct D–A type oligomers for efficient photocatalytic hydrogen generation. © 2021 Wiley-VCH GmbH

Developing high-performance catalysts for oxygen evolution reaction (OER) is critical for the widespread applications of clean and sustainable energy through electrochemical devices such as zinc-air batteries and (photo)electrochemical water splitting. Constructing heterostructure and oxygen vacancies have demonstrated great promises to boost the OER performance. Herein, we report a facile strategy to fabricate hetero-structured NiFe

Although CRISPR/Cas9-mediated gene editing is widely applied to mimic human disorders, whether acute manipulation of disease-causing genes in the brain leads to behavioral abnormalities in non-human primates remains to be determined. Here we induced genetic mutations in MECP2, a critical gene linked to Rett syndrome (RTT) and autism spectrum disorders (ASDs), in the hippocampus (DG and CA1–4) of adolescent rhesus monkeys (Macaca mulatta) in vivo via adeno-associated virus (AAV)-delivered Staphylococcus aureus Cas9 with sgRNAs targeting MECP2. In comparison to monkeys injected with AAV-SaCas9 alone (n = 4), numerous autistic-like behavioral abnormalities were identified in the AAV-SaCas9-sgMECP2-injected monkeys (n = 7), including social interaction deficits, abnormal sleep patterns, insensitivity to aversive stimuli, abnormal hand motions and defective social reward behaviors. Furthermore, some aspects of ASDs and RTT, such as stereotypic behaviors, did not appear in the MECP2 gene-edited monkeys, suggesting that different brain areas likely contribute to distinct ASD symptoms. This study showed that acute manipulation of disease-causing genes via in vivo gene editing directly led to behavioral changes in adolescent primates, paving the way for the rapid generation of genetically engineered non-human primate models for neurobiological studies and therapeutic development.

Vapor generation using solar energy is emerging as an efficient technology for wastewater purification and seawater desalination to relieve global water crisis. However, salt deposition on the evaporation surface seriously impairs the long-term steady water evaporation performance. Herein, the flexible salt-rejecting photothermal paper comprising reduced graphene oxide (rGO) and ultralong hydroxyapatite nanowires (HNs) has been developed for high-performance solar energy-driven water evaporation and stable desalination of seawater. The rGO/HN photothermal paper has advantages such as the hierarchical porous structure, interconnected channels, high mechanical strength, high efficiencies of solar light absorption and photothermal conversion, fast water transportation, and good heat insulation and salt-rejecting properties. Furthermore, the hydrophilicity and hydrophobicity of the rGO/HN photothermal paper can be adjusted by regulating the thermal treatment time. The water evaporation rate and energy efficiency of the hydrophilic rGO/HN photothermal paper are 1.48 kg m-2 h-1 and 89.2%, respectively, under 1 sun illumination (1 kW m-2). The hydrophobic rGO/HN photothermal paper shows a long-time stable water evaporation and salt-rejecting performance in the process of seawater desalination. The flexible salt-rejecting rGO/HN photothermal paper can produce clean water from wastewater and seawater with high rejection rates of organic dyes, metal ions, and salt ions, and it is promising for applications in water purification and seawater desalination.

Binary transition metal selenides have been more promising than single transition metal selenides as anode materials for sodium-ion batteries (SIBs). However, the controlled synthesis of transition metal selenides, especially those derived from metal-organic-frameworks with well-controlled structure and morphology is still challenging. In this paper, highly porous NiCoSe

The frequent occurrence of oil spilling and industrial oily wastewater have serious negative effects on the marine ecosystem and human health. For this reason, high performance, effective, and cont...

Herein, we report a new kind of highly flexible hydroxyapatite nanowire (HAPNW)-based layered catalytic paper with a high thermal stability, excellent fire resistance, and high catalytic efficiency for continuous flow catalysis. A simple process has been developed for preparing and loading gold nanoparticles (AuNPs) on the fire-resistant HAPNW paper to obtain the HAPNW/AuNP layered catalytic paper. Oleic acid molecules adsorbed on the surface of HAPNWs can effectively reduce Au(III) ions to Au nanoparticles in situ in aqueous solution in the absence of an additional reducing reagent at room temperature. The size and weight percentage of AuNPs and surface hydrophilicity/hydrophobicity of the HAPNW/AuNP layered catalytic paper can be controlled. Benefiting from the nanoporous network and nanowire-based layered structure, the HAPNW/AuNP layered catalytic paper exhibits high catalytic activity for continuous flow reactions when the aqueous solution flows through the paper. Additionally, the HAPNW/AuNP layered catalytic paper can be easily recycled. Importantly, the HAPNW/AuNP layered catalytic paper shows excellent nonflammable properties and high catalytic stability after heat treatment. The HAPNW/AuNP layered catalytic paper has a high catalytic efficiency (100%), good recyclability, long-term stability, and high thermal stability in the continuous flow catalytic reduction of 4-nitrophenol. Furthermore, the catalytic degradation of organic dyes is also investigated. The HAPNW/AuNP layered catalytic paper is promising for applications in water treatment and high-temperature catalysis. In addition, the fire-resistant HAPNW-based paper can be used as an excellent support for various catalysts to prepare other kinds of catalytic paper for many applications.

Rapid cleanup of crude oil spills is a worldwide challenge because heavy oil components (>103 mPa·s) are difficult for removal by conventional porous oil sorbents due to their inherent high viscosities. In this work, we took advantage of the photothermal effect by using sunlight as the energy source to heat heavy oil components for significantly reducing their viscosities to achieve a fast crude oil cleanup. A carbon nanotube (CNT) modified lignin-based polyurethane foam was fabricated as a photothermal sorbent that exhibited outstanding adsorption capacity for heavy oil. The modified foam achieved nearly full sunlight absorption (97%) with its surface temperature reaching up to 90.3 °C within 500 s owing to the excellent photothermal effect of CNTs. The resulting solar heating effectively reduced the viscosity of the heavy oil, which enabled the modified foam to quickly adsorb more than six times (6.34 ± 0.27 g/g) of its weight of crude oil within 6 min under one sun illumination (1.00KW/m2). Meanwhile, the lignin-based foam adsorbents were degradable in alkaline environments and CNTs can be recovered from the same condition. They could reach a degradation efficiency of 88.03% in 2 mol/L NaOH aqueous solution at 80 °C for 10 h, and the degradation rate was as high as 6.25 mg/h. Given the novel structural design, excellent environmental friendliness, rapid oil adsorption rate, and high oil adsorption capacity, this work provides a promising solution for addressing catastrophic large-area viscous crude oil spills.

Zinc oxide is regarded as a promising candidate for application in photoelectrochemical water oxidation due to its higher electron mobility. However, its instability under alkaline conditions limits its application in a practical setting. Herein, we demonstrate an easily achieved wet-chemical route to chemically stabilize ZnO nanowires (NWs) by protecting them with a thin layer Fe2 O3 shell. This shell, in which the thickness can be tuned by varying reaction times, forms an intact interface with ZnO NWs, thus protecting ZnO from corrosion in a basic solution. The reverse energetic heterojunction nanowires are subsequently activated by introducing an amorphous iron phosphate, which substantially suppressed surface recombination as a passivation layer and improved photoelectrochemical performance as a potential catalyst. Compared with pure ZnO NWs (0.4 mA cm-2 ), a maximal photocurrent of 1.0 mA cm-2 is achieved with ZnO/Fe2 O3 core-shell NWs and 2.3 mA cm-2 was achieved for the PH3 -treated NWs at 1.23 V versus RHE. The PH3 low-temperature treatment creates a dual function, passivation and catalyst layer (Fe2 PO5 ), examined by X-ray photoelectron spectroscopy, TEM, photoelectrochemical characterization, and impedance measurements. Such a nano-composition design offers great promise to improve the overall performance of the photoanode material.

Graphitic carbon nitride (g-C3N4) has been widely studied as a metal-free photocatalyst, leading to some excellent results; however, the rapid recombination of photogenerated charge carriers substantially limits its performance. Here, we establish two types of g-C3N4-based heterojunction (type II and nonmediator assisted Z-scheme) photoanodes on a transparent conducting substrate via coupling with rod-like and nanoparticulate WO3, respectively. In these composites, g-C3N4 film grown by electrophoretic deposition of exfoliated g-C3N4 serves as the host or guest material. The optimized type II WO3/g-C3N4 composite exhibits an enhanced photocurrent of 0.82 mA cm-2 at 1.23 V vs. RHE and an incident photo-to-current conversion efficiency (IPCE) of 33% as compared with pure WO3 nanorods (0.22 mA cm-2 for photocurrent and 15% for IPCE). Relative to pure g-C3N4 film (with a photocurrent of several microampere and an IPCE of 2%), a largely improved photocurrent of 0.22 mA cm-2 and an IPCE of 20% were acquired for the Z-scheme g-C3N4/WO3 composite. The enhancement can be attributed to accelerated charge separation in the heterointerface because of the suitably aligned band gap between WO3 and g-C3N4, as confirmed by optical spectroscopy and ultraviolet photoelectron spectroscopy (UPS) analysis. The photocatalytic process and mechanism of the g-C3N4-based heterojunctions are proposed herein, which potentially explain the origin of the enhanced photoelectrochemical performance. This achievement and the fundamental information supplied here indicate the importance of rationally designing heterojunction photoelectrodes to improve the performance of semiconductors. This is particularly important for materials such as pure g-C3N4 and WO3, as their photoactivities are strongly restricted by high recombination rates.

Viral vector transfection systems are among the simplest of biological agents with the ability to transfer genes into the central nervous system. In brain research, a series of powerful and novel gene editing technologies are based on these systems. Although many viral vectors are used in rodents, their full application has been limited in non-human primates. To identify viral vectors that can stably and effectively express exogenous genes within non-human primates, eleven commonly used recombinant adeno-associated viral and lentiviral vectors, each carrying a gene to express green or red fluorescence, were injected into the parietal cortex of four rhesus monkeys. The expression of fluorescent cells was used to quantify transfection efficiency. Histological results revealed that recombinant adeno-associated viral vectors, especially the serotype 2/9 coupled with the cytomegalovirus, human synapsin I, or Ca2+/calmodulin-dependent protein kinase II promoters, and lentiviral vector coupled with the human ubiquitin C promoter, induced higher expression of fluorescent cells, representing high transfection efficiency. This is the first comparison of transfection efficiencies of different viral vectors carrying different promoters and serotypes in non-human primates (NHPs). These results can be used as an aid to select optimal vectors to transfer exogenous genes into the central nervous system of non-human primates.

Rational design and constructing multifunctional electrocatalysts featuring with low cost and high efficiency is critical for promoting the implement of sustainable energy devices such as water splitting and zinc air batteries. Herein, we report a facile means to prepare a selenide/sulfide hetero-structured NiCo2Se4/NiCoS4 catalyst for oxygen evolution reaction (OER), hydrogen evolution reaction (HER), overall water splitting (OWS), and Zn-air batteries (ZABs). The NiCo2Se4/NiCoS4 heterostructure showed excellent OER and HER performance, evidenced by the small overpotential of 248 mV and 180 mV @ 10 mA cm−2 for OER and HER, and superior long-term stability to the benchmark IrO2 and Pt/C catalyst for OER and HER, respectively. It also exhibited a potential of 1.660 V @ 10 mA cm−2 in the practical OWS test, close to the Pt/C + IrO2 catalyst. Furthermore, when employed as air-cathode catalyst for ZABs, the NiCo2Se4/NiCoS4 modified battery exhibited the narrow charge-discharge voltage gap of 0.98 V @ 50 mA cm−2 and a maximal specific capacity of 693.17 mA h g−1, outperforming the IrO2 counterpart. Such excellent performance can be attributed to the advantageous structural merit of the NiCo2Se4 nanoflowers, and especially the heterostructure interfaces created in NiCo2Se4/NiCoS4, which significantly boosted the catalytic synergistic effects. This study can offer a new avenue to design and prepare abundant-element-based cost effective, efficient and durable electrocatalysts with multifunctionalities that hold great promises to be applied in electrochemical devices.

A variety of biological materials in natural organisms supply a rich source of structural design guidelines and inspirations for the construction of advanced structural materials with excellent mechanical properties. In this work, inspired by the natural nacre and human bone, a kind of flexible macroscopic ribbon fiber made from highly ordered alignment of ultralong hydroxyapatite (HAP) nanowires and sodium polyacrylate (PAAS) with a "brick-and-mortar" layered structure has been developed by a scalable and convenient wet-spinning method. The quasi-long-range orderly liquid crystal of one-dimensional ultralong hydroxyapatite nanowires is employed and spun into the continuous flexible macroscopic ribbon fiber. In this work, highly ordered ultralong HAP nanowires act as the hard "brick" and PAAS acts as the soft "mortar", and the nacre-mimetic layered architecture is obtained. The as-prepared flexible macroscopic HAP/PAAS ribbon fiber exhibits superior mechanical properties, and the maximum tensile strength and Young's modulus are as high as 203.58 ± 45.38 MPa and 24.56 ± 5.35 GPa, respectively. In addition, benefiting from the excellent flexibility and good knittability, the as-prepared macroscopic HAP/PAAS ribbon fiber can be woven into various flexible macroscopic architectures. Additionally, the as-prepared flexible macroscopic HAP/PAAS ribbon fiber can be further functionalized by incorporation of various functional components, such as magnetic and photoluminescent constituents. The as-prepared flexible macroscopic HAP/PAAS ribbon fiber has potential applications in various fields such as smart wearable devices, optical devices, magnetic devices, and biomedical engineering.

Graphitic carbon nitride (g-C

Developing high surface area nanostructured electrodes with fast charge separation is one of the main challenges for exploring cupric oxide (CuO)-based photocathodes in solar-driven hydrogen production applications. Herein, brand new 1D branched CuO nanowire arrays have been achieved on fluorine-doped tin oxide-coated glass (FTO) through a two-step wet chemical redox reaction. X-ray diffraction patterns, Raman spectra and X-ray photoelectron spectroscopy confirm the pure phase characteristic of the resulting branched CuO. In addition to the enlarged surface area of this advanced functional structure as compared with that of the 1D wire trunk, the charge injection and separation have been improved by rationally controlling the density of defects and size of branches. As a result, the optimized branched CuO exhibits photocurrent as high as 3.6 mA·cm−2 under AM 1.5G (100 mW·cm−2) illumination and 3.0 mA·cm−2 under visible light (λ > 420 nm) at 0.2 V vs. RHE in 0.5 M Na2SO4, which are 2.8- and 3.0-fold greater than those of 1D wire samples, respectively. In addition, the solution-processed approach established herein seems quite favourable for large-scale and low-cost manufacturing.

Six metal complexes were synthesized by the reaction of Co(II), Ni(II) nitrate with the first ligand of Glycylglycine (Gly-gly) and the second ligand of 2,2′-bipyridine (2,2′-bpy)/4,4′-bipyridine (4,4′-bpy)/1,10-phenanthroline (Phen) in water solution (pH = 8.0–8.2). The compositions of these complexes were characterized by elemental analysis, thermal gravimetric analysis-differential thermal analysis (TG/DTA), infrared spectral (IR) method, and nuclear magnetic resonance (1H NMR) method. The superoxide dismutase (SOD)-like activities and the interaction with human serum albumin (HSA) of these complexes were investigated. The results showed that all of the Co(II), Ni(II) complexes had the composition of [M(Gly-gly)(2,2′-bpy/Phen)(H2O)]·2H2O and [M2(Gly-gly)2(4,4′-bpy)(H2O)4]·4H2O. Meanwhile, the IC50 of the complexes was about 0.327–0.564 μM that means the complexes have good SOD-like activities. The fluorescence spectra showed that these complexes could combine with HSA and be delivered by HSA molecules in human blood.

Oriented, Crystalline Anatase TiO2 Nanorods on Transparent Conducting Electrodes Dong-Dong Qin,† Ying-Pu Bi,‡ Xin-Jian Feng, Wei Wang, Greg D. Barber, Ting Wang,† Yu-Min Song,† Xiao-Quan Lu,† and Thomas E. Mallouk* †Key Lab of Bioelectrochemistry and Environmental Analysis of Gansu, College of Chemistry and Chemical Engineering, The Northwest Normal University, Lanzhou, Gansu 730070, People’s Republic of China Department of Chemistry and Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, United States ‡National Engineering Research Center for Fine Petrochemical Intermediates, Lanzhou Institute of Chemical Physics, Chinese Acadamy of Sciences, Lanzhou, Gansu 730000, People’s Republic of China Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Acadamy of Sciences, Suzhou, Jiangsu 215123, People’s Republic of China

Sn-doped hematite films were electrochemically deposited on a fluorine-doped tin oxide substrate for use as an anode for photoelectrochemical water oxidation. A high photocurrent of ∼2.8 mA cm−2 at 1.24 V vs. RHE and a conversion efficiency of 0.24% are achieved.

Zinc oxide is regarded as a promising candidate for application in photoelectrochemical water oxidation due to its higher electron mobility. However, its instability under alkaline conditions limits its application in a practical setting. Herein, we demonstrate an easily achieved wet-chemical route to chemically stabilize ZnO nanowires (NWs) by protecting them with a thin layer Fe

Graphitic carbon nitride (g-C

Photoelectrochemical water splitting directly converts solar energy to chemical energy stored in hydrogen, a high energy density fuel. Although water splitting using semiconductor photoelectrodes has been studied for more than 40 years, it has only recently been demonstrated using dye-sensitized electrodes. The quantum yield for water splitting in these dye-based systems has, so far, been very low because the charge recombination reaction is faster than the catalytic four-electron oxidation of water to oxygen. We show here that the quantum yield is more than doubled by incorporating an electron transfer mediator that is mimetic of the tyrosine-histidine mediator in Photosystem II. The mediator molecule is covalently bound to the water oxidation catalyst, a colloidal iridium oxide particle, and is coadsorbed onto a porous titanium dioxide electrode with a Ruthenium polypyridyl sensitizer. As in the natural photosynthetic system, this molecule mediates electron transfer between a relatively slow metal oxide catalyst that oxidizes water on the millisecond timescale and a dye molecule that is oxidized in a fast light-induced electron transfer reaction. The presence of the mediator molecule in the system results in photoelectrochemical water splitting with an internal quantum efficiency of approximately 2.3% using blue light.

The controlled growth of highly ordered, [211]-oriented FeOOH nanowire arrays on various substrates, such as Pt, W, Ti, and fluoride-doped tin oxide (FTO) glass, was achieved by a solvothermal method in aqueous acetonitrile solutions at 80-120 degrees C, following by annealing to form alpha-Fe2O3 nanowires with their [110] direction perpendicular to the substrate. Adjusting the reaction pH and temperature enables control of the nanowire length. In particular, the pH has a dramatic effect on the nanowire growth, with low pH resulting in the growth of longer wires because of the acid-catalyzed hydrolysis of acetonitrile. Photoactive hematite was prepared by diffusing Ti or Sn into the nanowires during thermal annealing. Processing parameters that influenced the photoelectrochemical performance of these nanowire arrays, including the annealing regime, temperature, and length of nanowires, are discussed in detail. The Ti- and Sn-doped one-dimensional [110)-oriented alpha-Fe2O3 nanowire arrays provide an effective pathway for electron transport, demonstrating increased photocurrents, up to 1.3 mA/cm(2) under air mass 1.5 global (AM 1.5G) illumination, in photoelectrochemical water oxidation.

Efficient utilization of abundant solar energy for clean water generation is considered a sustainable and environment friendly approach to mitigate the global water crisis. For this purpose, this study reports a flexible fire-resistant photothermal paper by combining carbon nanotubes (CNTs) and fire-resistant inorganic paper based on ultralong hydroxyapatite nanowires (HNs) for efficient solar energy-driven water steam generation and water purification. Benefiting from the structural characteristics of the HN/CNT photothermal paper, the black CNT surface layer exhibits a high light absorbability and photothermal conversion capability, the HN-based inorganic paper acts as a thermal insulator with a high temperature stability, low thermal conductivity, and interconnected porous structure. By combining these advantages, high water evaporation efficiencies of 83.2% at 1 kW m-2 and 92.8% at 10 kW m-2 are achieved. In addition, the HN/CNT photothermal paper has a stable water evaporation capability during recycling and long-time usage. The promising potential of the HN/CNT photothermal paper for efficient production of drinkable water from both actual seawater and simulative wastewater samples containing heavy metal ions, dyes, and bacteria is also demonstrated. The highly flexible HN/CNT photothermal paper is promising for application in highly efficient solar energy-driven seawater desalination and wastewater purification.