Latest ArticlesTiO2-based films are one of the most attractive photocatalysts owing to their highly cost-effective properties. Nevertheless, most TiO2-based photocatalytic films for dye degradation are in the form of robust films (without flexibility), TiO2 coatings on carbon matrix (with leakage risk), or surface-covered TiO2 hybrids (not favorite to contact with external molecules). Therefore, the development of durable and highly efficient TiO2 photocatalytic films for dye degradation is still needed. Here, we fabricated soft photocatalytic hybrid membranes (TANFs) from TiO2 nanotubes (TiNT) and aramid nanofiber (ANF) by a facile vacuum filtration process. The similar morphology and dimension of TiNT and ANF enable them intricately intertwine with each other in the membrane network. Under an appropriate mixing ratio, the TANF exhibited significantly improved optical and mechanical properties. When used for dye degradation, the membrane showed excellent photocatalytic performance and could keep stable activity and integrated state for repeated usage.
Sulfidation of zero-valent iron (ZVI) has attracted broad attention in recent years for improving the sequestration of contaminants from water. However, sulfidated ZVI (S-ZVI) is mostly synthesized in the aqueous phase, which usually causes the formation of a thick iron oxide layer on the ZVI surface and hinders the efficient electron transfer to the contaminants. In this study, an alcohothermal strategy was employed for S-ZVI synthesis by the one-step reaction of iron powder with elemental sulfur. It is found that ferrous sulfide (FeS) with high purity and fine crystallization was formed on the ZVI surface, which is extremely favorable for electron transfer. Cr(Ⅵ) removal experiments confirm that the rate constant of S-ZVI synthesized by the alcohothermal method was 267.1- and 5.4-fold higher than those of un-sulfidated ZVI and aqueous-phase synthesized S-ZVI, respectively. Systematic characterizations proved that Cr(Ⅵ) was reduced and co-precipitated on S-ZVI in the form of a Fe(Ⅲ)/Cr(Ⅲ)/Cr(Ⅵ) composite, suggesting its environmental benignancy.
Metal-organic frameworks (MOFs) combined with specific ligands are highly adaptable smart materials that can respond to external and physiological stimuli. In this study, we introduced a pyridinyl zwitterionic ligand with light/pH dual response into magnetic MOF composite (Fe3O4@ZW-MOF) for enrichment of phosphorylated peptides for the first time. The introduction of the developed ligand gives MOF material dual response properties. Light stimulation affects the generation/disappearance of free radicals of the pyridine derivative, resulting in a change in the charge gradient of the zwitterion, and zwitterion can also regulate the pH of the solution by adding acid or base. Therefore, the reversible capture and release of phosphorylated peptides can be easily achieved by adjusting light and pH. The established phosphorylated peptide enrichment platform exhibits high sensitivity (detection limit of 1 fmol), high selectivity (β-casein: BSA, 1:1000), and good reusability (7 cycles). In addition, the method was applied to the enrichment of phosphorylated peptides in complex systems (non-fat milk and human serum), demonstrating the feasibility of this method for phosphoproteom analysis. In conclusion, the synthesized Fe3O4@ZW-MOF is a promising MOF material, which provides the possibility to advance the application of responsive MOFs materials in proteomics.
Aqueous perfluorooctanoic acid (PFOA) elimination has raised significant concerns due to its persistence and bioaccumulation. Although β-PbO2 plate anodes have shown efficient mineralization of PFOA, it remains unclear whether PFOA can be effectively degraded using β-PbO2 reactive electrochemical membrane (REM). Herein, we assessed the performance of Ti/SnO2-Sb/La-PbO2 REM for PFOA removal and proposed a possible degradation mechanism. At a current density of 10 mA/cm2 and a membrane flux of 8500 (liters per square meter per hour, LMH), the degradation efficiency of 10 mg/L PFOA was merely 8.8%, whereas the degradation efficiency of 0.1 mg/L PFOA increased to 96.6%. Although the porous structure of the β-PbO2 REM provided numerous electroactive sites for PFOA, the generated oxygen bubbles in the pores could block the pore channels and adsorb PFOA molecules. These hindered the protonation process and significantly impeded the degradation of high-concentration PFOA. Quenching experiments indicated that •OH played dominant role in PFOA degradation. The electrical energy per order to remove 0.1 mg/L PFOA was merely 0.74 Wh/L, which was almost an order of magnitude lower than that of other anode materials. This study presents fresh opportunities for the electrochemical degradation of low-concentration PFOA using β-PbO2 REM.
Developing low-loading single-atom catalysts with superior catalytic activity and selectivity in formaldehyde (HCHO) oxidation at room temperature remains challenging. Herein, ZrO2 nanoparticles coupled low-loading Ir single atoms in N-doped carbon (Ir1-N-C/ZrO2) was prepared. The optimal Ir1-N-C/ZrO2 with 0.25 wt% Ir loading delivers the high HCHO removal and conversion efficiency (> 95%) at 20 ℃, which is higher than that over Ir1-N-C with the same Ir loading. The specific rate can reach 1285.6 mmol gIr−1 h−1, surpassing the Ir based catalysts reported to date. Density functional theory calculation results and electron spin resonance spectra indicate that the introduction of ZrO2 nanoparticles modulate the electronic structure of the Ir single atoms, promoting O2 activation to •O2–. Moreover, the Ir-C-Zr channel is favorable for the dissociation of •O2– to active oxygen atom (*O), and further accelerates the transformation of HCHO and intermediates (dioxymethylene and formates) to CO2 and H2O. This work provides a facile strategy to design low-loading single-atom catalysts with high catalytic activity toward HCHO oxidation.
In recent years, the application of smartphone in various fields has received great attention, and it has become a promising tool in virus detection, data processing and data exchange. During the rapid spread of COVID-19 around the world, many traditional detection methods have been combined with smartphone to assist in the analysis and detection of the novel coronavirus (SARS-CoV-2), including electrochemistry, fluorescence and colorimetry. With the gradual development of artificial intelligence (AI), the combination of AI and smartphone to analyze SARS-CoV-2 was also the focus of research. Based on the summary of the traditional methods combined with smartphone to detect SARS-CoV-2 virus, in addition to AI-based data processing, AI algorithms are also employed for SARS-CoV-2 detection itself. This review discussed both strategies and focused on the application of the former. The combination of AI algorithm and smartphone to detect SARS-CoV-2 has high accuracy, which is more conducive to meeting the needs of portable detection. In addition, the classification of SARS-CoV-2 virus samples in biological fluids such as blood and saliva was also discussed. Finally, this paper briefly discussed the limitations of using smartphone analysis to detect SARS-CoV-2, as well as the prospect and future development of virus detection. In conclusion, the detection methods based on smartphone and AI algorithms show great potential in the detection of SARS-CoV-2 and can be a valuable complement to traditional analysis methods.
Cobalt-based phosphides show excellent hydrogen evolution reaction (HER) performance, however, improving the intrinsic activity and stability of it in alkaline electrolyte still remains a challenge. Herein, CoRuOH/Co2P/CF with heterojunction structure was developed by means of molten salt and rapid hydrolysis (30 s). The OH− from rapid surface hydrolysis of Co2P as a hydrogen adsorption site can facilitate the formation of thin CoRuOH layer as a water dissociation site, which may bring out better synergistic effect for alkaline HER. Moreover, the covering of CoRuOH can improve the stability of Co2P for HER. When drives at 100 mA/cm2, it only requires overpotential of 81 mV in 1.0 mol/L KOH (25 ℃). Even at higher current density (1000 mA/cm2), CoRuOH/Co2P/CF can also operate stability for at least 100 h. When coupling with NiFe-LDH/IF in a two-electrode system, the voltage of NiFe-LDH/IF(+) || CoRuOH/Co2P/CF(−) at 1000 mA/cm2 is merely 1.77 V with 100 h, demonstrating great potential for water splitting. The implementation of this work provides a new strategy and reference for the further improvement of transition metal phosphides as HER electrocatalysts.
Dynamic DNA nanotechnology plays a significant role in nanomedicine and information science due to its high programmability based on Watson-Crick base pairing and nanoscale dimensions. Intelligent DNA machines and networks have been widely used in various fields, including molecular imaging, biosensors, drug delivery, information processing, and logic operations. Encoders serve as crucial components for information compilation and transfer, allowing the conversion of information from diverse application scenarios into a format recognized and applied by DNA circuits. However, there are only a few encoder designs with DNA outputs. Moreover, the molecular priority encoder is hardly designed. In this study, we introduce allosteric DNAzyme-based encoders for information transfer. The design of the allosteric domain and the recognition arm allows the input and output to be independent of each other and freely programmable. The pre-packaged mode design achieves uniformity of baseline dynamics and dynamics controllability. We also integrated non-nucleic acid molecules into the encoder through the aptamer design of the allosteric domain. Furthermore, we developed the 2-n encoder and the Endo Ⅳ-assisted priority encoder inspired by immunoglobulin's molecular structure and effector patterns. To our knowledge, the proposed encoder is the first enzyme-free DNA encoder with DNA output, and the priority encoder is the first molecular priority encoder in the DNA reaction network. Our encoders avoid complex operations on a single molecule, and their simple structure facilitates their application in complex DNA circuits and biological scenarios.
Pyrite-type sulfides (PTS) exhibit promising intrinsic activities for oxygen reduction and evolution reactions (ORR/OER). However, their poor electrical conductivities may limit the charge transfer rate to inevitably lower activity. Here, yolk-shell structured cobalt-pyrite nanospheres (CoS2 YSS) are prepared and modified with amino groups as nucleation sites for coupling highly-conductive needle-like nitrogen-doped carbon via a facile solvothermal method (CoS2 YSS@NC). The as-marked CoS2 YSS@NC-0.5 shows a gap between yolk and shell, and an obvious exterior layer of grafted NC, which can provide an integrated structure, an interior place, and three exposed surfaces on CoS2. CoS2 YSS@NC-0.5 reveals higher ORR activity (half-wave potential of 0.88 V) and methanol resistance than commercial Pt/C. Due to in-situ formation of highly-active CoOOH, CoS2 YSS@NC-0.5 shows a better overpotential (244 mV at 10 mA/cm2) and Tafel slope (135 mV/dec) than RuO2. Zinc-air battery with CoS2 YSS@NC-0.5 air-cathode exhibits good open circuit potential (1.44 V), specific capacity (772.5 mAh/g) and cycling stability. Needle-like NC layer coated on the yolk-shell structure of CoS2 effectively lowers the charge transfer resistance to obtain extraordinary ORR/OER activities. It indicates that the integration of highly-conductive carbon onto pyrite-type sulfides is an effective strategy to acquire durable bifunctional ORR/OER catalysts.
Herein, we unveil the intelligent detection of multiple catechol isomers in complex environments utilizing both laser-induced graphene (LIG) and artificial neural network (ANN). The large scale-up manufacturing of LIG-based sensors (LIGS) with three-electrode configuration on polyimide (PI) is achieved by direct laser-writing and screen-printing technologies. Our LIGS shows excellent electrochemical performance toward catechol isomers, i.e., hydroquinone (1, 4-dihydroxybenzene, HQ), catechol (1, 2-dihydroxybenzene, CT), and resorcinol (1, 3-dihydroxybenzene, RC), with a low limit of detection (LOD) (CC, 0.079 µmol/L; HQ, 0.093 µmol/L; RC, 1.18 µmol/L). Moreover, the ANN model is developed for machine-intelligent to predict concentrations of catechol isomers under an interfering environment via a single LIGS. Using six unique parameters extracted from the differential pulse voltammetry (DPV) response, the machine learning-based regression provides a coefficient of correlation with 0.998 and is able to correctly predict the total and individual concentrations in complex river samples. Hence, this work provides a guide for the preparation and application of LIGS via facile and cost-efficient mass production and the development of an intelligent sensing platform based on the ANN model.
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62662699(Operation and Technical Support)
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
