The loading of Fe ions on N-doped carbon nanosheets to boost photocatalytic cascade for water disinfection.

The pervasive presence of pathogenic bacteria in water environment poses a serious threat to public health. Here, a photocatalytic cascade was developed to reveal great water disinfection. Firstly, N-doped carbon nanosheets (N-CNSs) about 30-50 nm in size were synthesized by a hydrothermal strategy. It revealed wide-spectrum photocatalysis for H2O2 generation via a typical two-step single-electron process. A Fenton agent (Fe ion) was loaded, N-CNSs-Fe can in-situ convert photocatalytic H2O2 into ·OH with high oxidation potential. Moreover, its Fenton active is three times greater than pure Fe2+ owing to electron enrichment from N-CNSs to Fe for Fe3+/Fe2+ cycle. Further investigation displayed that Fe loading also could decrease bad gap and promote charge separation to boost photocatalysis. In addition, N-CNSs-Fe possesses positive surface potential to exhibit strong interaction with negative bacteria, facilitating the capture. Therefore, the nanocomposite can effectively inactivate E. coli with a lethality rate of 99.7 % under stimulated sunlight irradiation. In addition, it also was employed to treat a complex lake water sample, revealing great antibacterial (95.1 %) and dye-decolored (92.3 %) efficiency at the same time. With novel biocompatibility and antibacterial ability, N-CNSs-Fe possessed great potential for water disinfection.

An Intelligent and Soluble Microneedle Composed of Bi/BiVO4 Schottky Heterojunction for Tumor Ct Imaging and Starvation/Gas Therapy-Promoted Synergistic Cancer Treatment.

Phototherapy and sonodynamic therapy (SDT) are widely used for the synergistic treatment of tumors and have received considerable attention. However, an inappropriate tumor microenvironment, including pH, H2O2, oxygen, and glutathione levels, can reduce the therapeutic effects of synergistic phototherapy and SDT. Here, a novel Bi-based soluble microneedle (MN) is designed for the CT imaging of breast tumors and starvation therapy/gas therapy-enhanced phototherapy/SDT. The optimized Bi/BiVO4 Schottky heterojunction serves as the tip of the MN, which not only has excellent photothermal conversion ability and CT contrast properties, but its heterojunction can also avoid the rapid combination of electrons and hole pairs, thereby enhancing the photodynamic/sonodynamic effects. A degradable MN with excellent mechanical properties is fabricated by optimizing the ratios of poly(vinyl alcohol), poly(vinyl pyrrolidone), and sodium hyaluronate. Glucose oxidase (GOx) and diallyl trisulfide are loaded into the MN to achieve tumor starvation and gas therapy, respectively; And the controlled release of GOx and H2S can be achieved under ultrasound or near-infrared laser irradiation. The in vitro and in vivo results demonstrate that this multifunctional MN can achieve high therapeutic efficacy through starvation therapy/gas therapy-enhanced phototherapy/SDT. The designed multifunctional MN provides a prospective approach for synergistic phototherapy and SDT.

A dual-functional cuprum coordination framework for high proton conduction and electrochemical dopamine detection.

The present study selected 5, 5'-((6-(ethylamino)-1, 3, 5-triazine-2, 4-diyl) bis(azanediyl))diisophthalic acid (H4EATDIA) as ligand and an amino-functionalized cuprum-based MOF (EA-JUC-1000), successfully synthesized by microwave-assisted method, for proton conduction and dopamine sensing applications. In order to enhance the proton-conducting potential of EA-JUC-1000, the Brönsted acid (BA) encapsulated composites (BA@EA-JUC-1000) are dopped into chitosan (CS) to form a series of hybrid membranes (BA@EA-JUC-1000/CS). The impedance results display that the best proton conductivity of CF3SO3H@EA-JUC-1000/CS-8% reaches up to 1.23 × 10-3 S∙cm-1 at 338 K and ~ 98% RH, 2.6-fold than that of CS. Moreover, the EA-JUC-1000 is in-situ combined with reduced graphene oxide (rGO) (rGO/EA-JUC-1000), which makes EA-JUC-1000 have a wide detection range (0.1 ~ 500 µM) and a low limit of detection (50 nM), together with good anti-interference performance, reproducibility and repeatability. In addition, the electrochemical sensing method has been successfully applied to detect DA in bovine serum samples. The dual-functional MOF-based hybrid membrane and composites including proton conduction and DA sensing would provide an example of practical application for MOFs.

Porous Molybdenum Nitride Nanosphere as Carrier-Free and Efficient Nitric Oxide Donor for Synergistic Nitric Oxide and Chemo/Sonodynamic Therapy.

Given its abundant physiological functions, nitric oxide (NO) has attracted much attention as a cancer therapy. The sensitive release and great supply capacity are significant indicators of NO donors and their performance. Here, a transition metal nitride (TMN) MoN@PEG is adopted as an efficient NO donor. The release process starts with H+-triggered denitrogen owing to the high electronegativity of the N atom and weak Mo-N bond. Then, these active NHx are oxidized by O2 and other reactive oxygen species (ROS) to form NO, endowing specific release to the tumor microenvironment (TME). With a porous nanosphere structure (80 nm), MoN@PEG does not require an extra carrier for NO delivery, contributing to ultrahigh atomic utilization for outstanding release ability (94.1 ± 5.6 µM). In addition, it can also serve as a peroxidase and sonosensitizer for anticancer treatment. To further improve the charge separation, MoN-Pt@PEG was prepared to enhance the sonodynamic therapy (SDT) effect. Accordingly, ultrasound (US) further promotes NO generation due to more ROS generation, facilitating in situ peroxynitrite (·ONOO-) generation with great cytotoxicity. At the same time, the nanostructure also degrades gradually, leading to high elimination (94.6%) via feces and urine within 14-day. The synergistic NO and chemo-/sono-dynamic therapy brings prominent antitumor efficiency and further activates the immune response to inhibit metastasis and recurrence. This work develops a family of NO donors that would further widen the application of NO therapy in other fields.

Modulation of defects in metal organic gels to enhance anhydrous proton conduction from subzero to moderate temperature.

Exploitation of solid-state proton-conducting materials with high anhydrous proton conductivity from subzero temperature (<273 K) to moderate temperature (>353 K) is a great challenge. Here, Brönsted acid-dopped zirconium-organic xerogels (Zr/BTC-xerogels) are prepared for anhydrous proton conduction from subzero to moderate temperature. Abundant acid sites and strong H-bonding interactions make the CF3SO3H (TMSA)-introduced xerogel gain high proton conductivity from 9.0 × 10-4 S cm-1 (253 K) to 1.40 × 10-2 S cm-1 (363 K) under anhydrous conditions, which are in the leading level. This provides a new possibility to develop wide-operating-temperature conductors.

Portable smartphone-integrated AuAg nanoclusters electrospun membranes for multivariate fluorescent sensing of Hg2+, Cu2+ and l-histidine in water and food samples.

Detection of heavy metals have been pivotal due to their non-biodegradability and food chain accumulation. Herein, a multivariate ratiometric sensor was developed by in situ integrating AuAg nanoclusters (NCs) into electrospun cellulose acetate nanofibrous membranes (AuAg-ENM) for visual detection of Hg2+, Cu2+ and consecutive sensing of l-histidine (His), which was integrated into a smartphone platform for quantitative on-site detection. AuAg-ENM achieved multivariate detection of Hg2+ and Cu2+ by fluorescence quenching, and subsequent selective recovery of the Cu2+-quenched fluorescence by His, which distinguished Hg2+ and Cu2+ and fulfilled determination of His simultaneously. Notably, AuAg-ENM achieved selective monitoring of Hg2+, Cu2+ and His in water, food and serum samples with high accuracy comparable to ICP and HPLC tests. A logic gate circuit was devised to further explain and promote the application of AuAg-ENM detection by smartphone App. This portable AuAg-ENM provides a promising reference for fabricating intelligent visual sensors for multiple detection.

NIR-II driven photocatalytic hydrogen peroxide-supply on metallic copper-nickel selenide (Cu-Ni0.85Se) nanoparticle for synergistic therapy.

Currently, finite intratumoral H2O2 content has restricted the efficacy of chemodynamic therapy (CDT). Here, Cu-Ni0.85Se@PEG nanoparticles are constructed to display intracellular NIR-II photocatalytic H2O2 supplement. The formation mechanism is explored to discover that H2O2 generation is dominated by photo-excited electrons and dissolved O2 via a typical sequential single-electron transfer process. Both density functional theory calculation and experimental data confirm its metallic feature that endows the great NIR-II absorption and photothermal conversion efficiency (59.6 %, 1064 nm). Furthermore, the photothermal-assisting consecutive interband and intraband transition in metallic catalyst contributes to the high redox capacity and efficient separation/transfer ability of photo-generated charges, boosting H2O2 production under 1064 nm laser irradiation. In addition, Cu-Ni0.85Se@PEG possess mimic peroxidase and catalase activity, leading to in-situ H2O2 activation to produce ∙OH and O2 for the enhanced CDT and hypoxia relief. What's more, the nanomaterials reveal novel biodegradation that is derived from oxidation from insolvable selenide into soluble selenate, resulting in elimination via feces and urine within 2 weeks. Synergistic CDT and photothermal therapy (PTT) further lead to great tumor inhibition and immune response for anti-tumor. The antitumor mechanism and the potential biological process also are investigated by high-throughput sequencing of expressed transcripts (RNAseq). The great treatment performance is responsible for the regulation of related oxidative stress and stimulus genes to induce organelle (mitochondrial) and membrane dysfunction. Besides, the synergistic therapy also can efficiently evoke immune response to further fight against tumor.

Defect-Rich Ni-CoO@PEG Porous Hexagonal Nanosheets: Multi-enzyme and Ultrasound Catalysis for Synergistic Anticancer Treatment.

Given the similarity with photocatalysis, sonodynamic therapy (SDT) can be defined as ultrasonic (US) catalysis. Encouraged by the principles of photocatalysis and defect chemistry, defect-rich nickel (Ni)-doped cobaltous oxide (Ni-CoO@PEG) porous hexagonal nanosheets have been synthesized as a sonosensitizer. The doping of Ni decreases the band gap that is testified by density functional theory to increase the US-generated charges. Under US irradiation, Ni-CoO@PEG nanosheets produce 1O2 as an active species that is determined by dissolved O2 and electrons. Moreover, the doping also brings abundant oxygen vacancies (OV) that not only are in favor of efficient separation of electron-hole but also enhance the interaction toward O2, boosting 1O2 generation. In addition, Ni-CoO@PEG shows robust mimic catalase (CAT) and peroxidase characterization to effectively improve the intratumor O2 content and oxidation stress. What is more, the nanosheets also possess glucose oxidase activity that can consume glucose to elevate the H2O2/acid level and to block the intracellular energy supply. The tandem nanozyme behaviors would further regulate the tumor microenvironment for assisting anticancer treatment. It is noted that Ni-CoO@PEG reveals a novel half-metallic feature endowing great magnetism and magnetic resonance imaging capacity. The above synergistic treatments exhibit outstanding anticancer performance that also evokes antitumor immunity to suppress metastasis and recurrence, efficiently.

l-Arginine-Modified CoWO4 /FeWO4 S-Scheme Heterojunction Enhances Ferroptosis against Solid Tumor.

Ferroptosis has recently attracted much attention as an anti-tumor therapy. Evidence suggests that ferroptosis can induce oxidative stress and accumulation of lethal lipid peroxides in cancer cells, leading to cell damage. However, unsuitable pH, H2 O2 levels, and high glutathione (GSH) expression in the tumor microenvironment hinder the development of ferroptosis-mediated therapy. In this study, an l-arginine (l-arg)-modified CoWO4 /FeWO4 (CFW) S-scheme heterojunction is strategically designed and constructed for ultrasound (US)-triggered sonodynamic- and gas therapy-induced ferroptosis. CFW not only has excellent Fenton-catalytic activity, outstanding GSH consumption capacity, and excellent ability to overcome tumor hypoxia, but its S-scheme heterostructure can also avoid the rapid combination of electron (e) and hole (h+ ) pairs, thereby enhancing the sonodynamic effects. As a precursor of nitric oxide (NO), l-arg is modified on the surface of CFW (CFW@l-arg) to achieve controlled NO release under US irradiation, thereby enhancing ferroptosis. In addition, poly(allylamine hydrochloride) is further modified on the surface of CFW@l-arg to stabilize l-arg and achieve controllable NO release. Both in vitro and in vivo results demonstrate that such a multifunctional therapeutic nanoplatform can achieve high therapeutic efficacy through sonodynamic and gas therapy-enhanced ferroptosis. This designed oncotherapy nanoplatform provides new inspiration for ferroptosis-mediated therapy.

Thermal-Response Proton Conduction in Schiff Base-Incorporated Metal-Organic Framework Hybrid Membranes under Low Humidity Based on the Excited-State Intramolecular Proton Transfer Mechanism.

Stimulus-responsive proton conduction materials have attracted enormous interest as a new kind of "smart material". It is desirable to develop the appropriate stimulus signal and high proton-conducting materials with an excellent proton-conducting switch ratio (γ), but it remains a great challenge. Here, it can be found for the first time that 4-((2-hydroxybenzylidene)amino)benzenesulfonic acid (HBABSA) has obvious thermal isomerization when porous solids act as matrixes at the ambient temperatures, which is different from that in the crystalline state at 77 K. Therefore, we proposed a host-guest metal-organic framework (MOF) composite, namely, MOF-808 incorporated with HBABSA (HBABSA@MOF-808), which has a proton-conducting switch ratio (γ) of 16 between 338 and 343 K due to the thermally induced isomerization of HBABSA molecules in the MOF pores. The strong binding between the keto-type HBABSA and MOF at the relatively low temperatures can efficiently suppress the proton conduction, while the enol-type one provides more mobile protons for conduction at the high temperatures due to the excited-state intramolecular proton transfer mechanism. Further, the HBABSA@MOF-808 as a filler is blended into polyvinyl alcohol and poly(2-acrylamide-2-methyl-1-propane sulfonic acid) to form hybrid membranes. The hybrid membrane with the highest content of the MOF composite displays a high proton conductivity of 5.57 × 10-3 S·cm-1 under 353 K and 57% RH along with a good switch ratio of 5.4. The development of thermal-response proton-conducting MOF materials is opening up a unique pathway for remote control, thermal sensing, intelligent batteries, and other fields.

Hollow CoP@N-Carbon Nanospheres: Heterostructure and Glucose-Enhanced Charge Separation for Sonodynamic/Starvation Therapy.

Sonodynamic therapy (SDT) can be described as ultrasonic (US) catalysis. Adequate charge separation is considered as effective means to promote reactive oxygen species (ROS). Here, hollow CoP@N-carbon@PEG (CPCs@PEG) nanospheres (∼60 nm) are prepared as sonosensitizers, showing greater ROS generation than pure CoP@PEG under US irradiation. Both 1O2 and ·O2- are activation species that are determined by O2 and electrons. The great SDT performance of CPCs@PEG is ascribed to the heterostructure which promotes the separation and transfer for US-generated electrons and holes. In addition, holes can be further captured by endogenous glucose that is in favor of electron aggregation and ROS generation. Moreover, the consumption of glucose would decrease intracellular ATP for starvation therapy. Given the higher oxidation ability of Co3+, CPCs@PEG nanospheres possess catalase (CAT) activity to convert H2O2 into O2 for assisting ROS generation. Moreover, they also can oxidize glutathione (GSH) as a mimic GSH oxidase to break intratumor redox balance, facilitating oxidative stress. More importantly, the nanocomposites reveal good degradation ability dominated by the oxidation from insoluble phosphide into soluble phosphate, accelerating elimination via urine and feces within 14 days. CPCs@PEG nanospheres integrate the above effects not only to reveal great tumor inhibition ability but also to excite immune activation for anticancer.

Z-scheme MoS2/Co3S4@PEG nanoflowers: Intracellular NIR-II photocatalytic O2 production facilitating hypoxic tumor therapy.

Intratumoral hypoxia, which is in favour of cancer cell proliferation, invasion and metastasis, also inhibits photodynamic therapy (PDT) badly. Herein, second near-infrared (NIR-II) photocatalytic O2 production is established to realize hypoxia relief. MoS2/Co3S4@PEG (MSCs@PEG) nanoflowers (100-150 nm) are prepared via a two-step hydrothermal method. These samples possess high NIR-II harvest and photothermal conversion (39.8 %, 1064 nm) ability. That not only reveals photothermal therapy (PTT) but also lifts the thermal energy of nanomaterials to replenish extra energy, making sure the co-excitation of MoS2 (1.14 eV) and Co3S4 (1.40 eV) by low-energy NIR-II (1064 nm, 1.16 eV) laser. The investigation of band structure further displays the Z-Scheme characterization of MSCs heterostructure. These photo-excited holes/electrons hold great redox ability to form O2 (water splitting) and reactive oxygen species (ROS), simultaneously. In addition, MSC-2@PEG can be served to mimic catalase, peroxidase, and glutathione (GSH) oxidase to further boost oxidative stress. It is noted that heterostructure discovers the greater nanozyme activity, attributing to the lower resistance for charge transfer. Moreover, MSC-2@PEG displays a novel biodegradation ability to induce the elimination via urine and faeces within 14 days. Given the superparamagnetic and photothermal effect, the nanocomposite can be used as magnetic resonance and photothermal imaging (MRI and PTI) contrast. Associated with dual-imaging, intracellular O2 supplementation, and synergistic chemotherapy (CDT)/PTT/PDT, MSC-2@PEG possess great tumor inhibition that also efficiently motivates immune response for anticancer.

Hollow Nanooxidase Enhanced Phototherapy Against Solid Tumors.

Although phototherapy has attracted extensive attention in antitumor field in recent years, its therapeutic effect is usually unsatisfactory because of the complexity and variability of the tumor microenvironment (TME). Herein, we report novel CoSn(OH)6@CoOOH hollow carriers with oxidase properties that can enhance phototherapy. Hollow CoSn(OH)6@CoOOH nanocubes (NCs) with a particle size of ∼160 nm were synthesized via a two-step process of coprecipitation and etching. These NCs can react with O2 to generate singlet oxygen without hydrogen peroxide and consume glutathione, and their hollow structure can be utilized to carry drug molecules. After loading indocyanine green (ICG) and 1,2-bis(2-(4,5-dihydro-1H-imidazol-2-yl)propan-2-yl) diazene dihydrochloride (AIPH), the resulting nanosystem (HCIA) exhibited enhanced phototherapy effects through the catalytic activity of oxidase, production of alkyl radicals, and consumption of glutathione. Cell and mouse experiments showed that HCIA combined with near-infrared laser irradiation significantly inhibited the growth of 4T1 tumors. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that PI3K-Akt and MAPK signaling pathways were highly relevant to this therapeutic system. Such hollow NCs with oxidase activity have considerable potential for the design of multifunctional drug delivery vehicles for tumor therapy.

Biodegradation Mn-CoS@carbon di-shell nanoheterostructure with enhanced nanozyme-mediated phototherapy.

The efficacy of phototherapy is dependent on intracellular O2 concentration and NIR harvest. Here, a simple nanoplatform with nanoenzyme mediated phototherapy enhances anticancer capacity. Mn-CoS@carbon (CMS/C) di-shell hollow nanospheres (50 nm) are synthesized successfully through two-step consecutive Kirkendall process. The nanoheterostructure reveals the higher near-infrared (NIR) light absorption and photothermal conversion rate of 66.3% than pure CoS (45.5%), owing to the decreased band gap and multi-reflection of incident light in the hollow structure. And CMS/C reveals the reactive oxygen species (ROS) production and nanoenzyme activities (mimic peroxidase and catalase) that are 6 and 2 times than those of pure CoS. Furthermore, the nanoenzyme exhibits NIR-enhanced abilities to produce more OH and O2 facilitating anticancer. In addition, it also depletes glutathione (mimicking glutathione oxidase), to disturb intracellular redox-homeostasis, boosting the increase of oxidative stress. With grafting bovine serum albumin (BSA) and drug loading, CMS/C@BSA-Dox integrated multi-therapy make the great anticancer effect in vitro and vivo. After that, the nanocomposite could be biodegraded and eliminated via urinary and feces within 14 days. Based on this work, the efficient charge-separation can be designed to reveal high performance nanoenzymes as well as photosensitizers for anticancer.

NIR-II-driven intracellular photocatalytic oxygen-generation on Z-Scheme iron sulfide/cobalt sulfide nanosheets for hypoxic tumor therapy.

Tumor hypoxia not only promotes the proliferation, invasion and metastasis of cancer cells but also seriously hinders photodynamic therapy (PDT). Here, second near-infrared (NIR-II) photocatalytic O2 generation is introduced to relieve hypoxia. FeS2/CoS2@PEG (FCs@PEG) nanosheets (∼80 nm) are prepared with Fe-Co layered double hydroxides (LDHs) as precursor. As-synthesized samples have great NIR-II harvest and photothermal conversion efficiency (50.5 %, 1064 nm). In addition, photothermal effect can elevate the thermal energy of nanocomposite to supply extra energy and to excite FeS2 (1.16 eV) and CoS2 (1.37 eV) simultaneously by low-energy NIR-II (1064 nm, 1.16 eV) irradiation. Band structure is further investigated to discover the Z-Scheme mechanism of FCs@PEG, whose photogenerated charges remains high redox potential to oxidize water forming O2 and to capture O2 producing reactive oxygen species (ROS), respectively. In addition, FC2@PEG enhances peroxidase and catalase activities attributing to the lower resistance for charge transfer in heterostructure. Besides, the nanocomposite also can be used as glutathione oxidase (GSHOD) to deplete GSH and break intracellular redox balance, facilitating oxidative stress. Most importantly, FC2@PEG reveals excellent biodegradation and elimination via feces and urine within 14 D. FCs@PEG integrate magnetic resonance and photothermal imaging (MRI and PTI), O2 in situ supply, and synergistic photothermal therapy (PTT)/PDT/chemotherapy (CDT) to arouse immune response for anticancer.

Plasmonic Bi nanoparticles encapsulated by N-Carbon for dual-imaging and photothermal/photodynamic/chemo-therapy.

In this work, the plasmonic Bi@N-Carbon@PEG-DOX nanocomposites were constructed to integrate the imaging and synergistic therapy in one nanoplatform. Here, Bi nanoparticles were encapsulated into the N-doped carbon nanomaterials via a simple solvothermal method. The accumulated adjacent semimetal Bi nanoparticles in Bi@N­carbon enhanced the local surface plasmon resonance (LSPR) to make the great NIR harvest and high photothermal converting efficiency (52.3%, Bi@C-2). And that also was confirmed by the Finite Difference Time Domain (FDTD) calculation. Moreover, the LSPR would induce the hot charges (polarization charges), which were captured by O2 and H2O molecules to form ROS for photodynamic therapy (PDT). And the heterostructure of Bi and N­carbon further improved the effective segregation of the hot charges, making the 6.9 times ROS production (Bi@C-2) in comparing with pure Bi sample. In view of the ultrahigh X-ray attenuation coefficient of Bi and great photothermal effect, Bi@N-Carbon@PEG possessed the outstanding computerized tomography (CT) and photothermal imaging capacity. Meanwhile, they also exhibited the favourable biodegradation ability, inducing the elimination via urine and feces within 14 day. The integration of the multi-model (CT and Thermal) imaging and the PTT/PDT/chemotherapy makes Bi@N­carbon@PEG-DOX to be a potential candidate for cancer treatment.

A multifunctional hydrogel dressing with antibacterial properties for effective wound healing.

We have developed a multifunctional hydrogel dressing (denoted as dressing-2 : 1) using silver-doped yolk-like nickel sulfide (Ag(8.5%)@NiS2-x), polyacrylamide (PAM), and chitosan (CS). Ag(8.5%)@NiS2-x has tremendous potential in antibacterial applications mainly due to the following advantages: (i) it has excellent optical absorption in the 200-2500 nm range and can be combined with near-infrared laser for photothermal therapy; (ii) it possesses peroxidase characteristic, which can catalyze low-concentration hydrogen peroxide to produce highly effective bactericidal hydroxyl radicals; (iii) silver doping gives it the ability to destroy the inherent components of bacteria. Moreover, the PAM/CS hydrogel can adsorb both bacteria and inflammatory secretions, enhancing the sterilization ability of Ag(8.5%)@NiS2-x and promoting tissue healing. Our work highlights the great potential of dressing-2 : 1 as a multifunctional hydrogel dressing for effective antibacterial wound healing.

High-performance free-standing microbial fuel cell anode derived from Chinese date for enhanced electron transfer rates.

Traditional anode materials have disadvantages like low specific surface area and poor electrical conductivity. Herein, carbonized Chinese dates (CCD) were synthesized as microbial fuel cells (MFC) anodes. The obtained materials exhibited excellent biocompatibility with fast start-up (within one day) and charge transfer (Rct 4.0 Ω). Their porous structure allows efficient ion transport and microbial community succession, favorable for long-term operation. The biomass analysis shows that CCD anodes can load higher weight of biomass. High-throughput sequencing (16S rRNA) discovered that CCD anode can enrich Geobacter spp., with highest abundance of 73.4%, much higher than carbon felt (CF, 39.2%). Benefit from these properties, the MFC with CCD anodes possess a maximum power density of 12.17 W m-3 (1.62 times of commercial carbon felt). In all, the CCD anode exhibits high performance with low cost and easy fabrication, certificating it a promising candidate for an ideal MFC anode material.

NIR-driven intracellular photocatalytic oxygen-supply on metallic molybdenum carbide@N-carbon for hypoxic tumor therapy.

The intracellular O2-supply not only can relieve tumor hypoxia but also enhance the effects of photodynamic therapy (PDT). In this work, metallic Mo2C@N-carbon@PEG nanoparticles were constructed to reveal the near infrared (NIR)-photocatalytic O2 generation and promote photodynamic therapy (PDT). Here, (NH4)6Mo7O24·4H2O nanorods and urea were adopted as resources that were calcined to obtain Mo2C@N-carbon nanoparticles (20 nm). All samples displayed high NIR absorption as well as photothermal conversion efficiency of up to 52.7 % (Mo2C@N-Carbon-3@PEG). The density functional theory calculations demonstrated the metallic characteristic of Mo2C and that the consecutive interband/intraband charge-transition was responsible for the high NIR harvest and redox ability of electron-hole pairs, making the NIR-photocatalytic O2 and reactive oxygen species (ROS) generation. In comparison with the pure Mo2C, the heterostructure displayed twice the performance due to the enhanced charge-segregation between Mo2C and N-carbon. Given the high X-ray absorption coefficient and photothermal ability, the nanocomposite could be used in novel computer tomography and photothermal imaging contrast. Furthermore, the novel biodegradation and metabolism behaviors of nanocomposites were investigated, which were reflected as elimination from the body (mouse) via feces and urine within 14 days. The as-synthesized Mo2C@N-Carbon@PEG nanocomposites integrated the dual-model imaging, intracellular O2-supply, and phototherapy into one nanoplatform, revealing its potential for anti-cancer therapy.

Abundant defects of zirconium-organic xerogels: High anhydrous proton conductivities over a wide temperature range and formic acid impedance sensing.

There exists a challenge to develop solid-state proton conductors with high conductivity not only at high working temperatures (>353 K) but at start-up temperature and even at subzero temperature (<273 K) in cold climates or high-altitude drones. Here we present a series of zirconium-organic xerogels (Zr/Fum-xerogels) with porosity and defectivity, supported by N2 sorption, thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS), exhibiting a high anhydrous proton conductivity over the temperature range of 233 to 433 K. The anhydrous conductivity of Zr/Fum-xerogel-0.04 reaches 5.68 × 10-4 (233 K) and 2.5 × 10-2 S cm-1 (433 K), situating in the leading level of all anhydrous conductors reported to date. Further, the defective effects on acidities and conductive mechanisms of xerogels, especially structural changes of water clusters generated by varying temperatures are investigated by ion exchange capacity (IEC), X-ray photoelectron spectroscopy (XPS), temperature programmed desorption of NH3 (NH3-TPD) and in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The zirconium-organic xerogels with outstanding conducting performance is further implemented as impedance sensor towards formic acid.