Latest ArticlesRapid carrier recombination and slow charge transfer dynamics have significantly reduced the performance of photocatalytic hydrogen production. Construction of heterojunctions via utilizing the sulfur-edge and metal-edge sites of metal sulfide semiconductor for improving photocatalytic activity remains a significant challenge. Herein, a novel ZnIn2S4/MnS S-scheme heterojunction was prepared by hydrothermal synthesis to accelerate charge carrier transfer for efficient photocatalysis. Notably, ZnIn2S4/MnS exhibited excellent photocatalytic hydrogen evolution activity (7.95 mmol g−1 h−1) under visible light irradiation (≥420 nm), up to 4.7 times higher than that of pure ZnIn2S4. Additionally, cycling experiments showed that ZM-2 remained high stability after four cycles. Density-functional theory (DFT) calculations and in situ XPS results confirm the formation of S-scheme heterojunction, indicating that the tight interfacial contact between ZnIn2S4 and MnS with the presence of Mn-S bonds (the unsaturated Mn edges of MnS and the uncoordinated S atoms in the edge of ZnIn2S4) promoted faster charge transfer. Besides, the unsaturated S atom on the surface of MnS is an active site with strong H+ binding ability, which can effectively reduce the overpotential or activation barrier for hydrogen evolution. This study illustrates the critical influence of the interfacial Mn-S bond on the ZnIn2S4/MnS S-scheme heterojunction to achieve efficient photocatalytic hydrogen production and provides relevant guidance for carrying out rational structural/interfacial modulation.
Carbon emissions from wastewater treatment contribute to global warming and have received widespread attention. It is necessary to seek low-carbon wastewater treatment technologies. Microbial fuel cells (MFC) and osmotic microbial fuel cells (OsMFC) are low-carbon technologies that enable both wastewater treatment and energy recovery. In this study, MFC and OsMFC were used to treat sulfamethoxazole (SMX) wastewater, and direct carbon emissions during operation was calculated. The highest SMX removal rate can reach about 40%. Simultaneously, the CH4 emission factor was significantly reduced to <6 g CO2/kg of chemical oxygen demand. The accumulation of SMX-degrading bacteria competed with methanogens for carbon source utilization, leading to a significant decrease in the relative abundance of methanogens. It is hoped that this study can provide a sustainable approach to antibiotic wastewater treatment and promote the development of low-carbon wastewater treatment technologies.
Broadband photothermal and photoacoustic agents in the near-infrared (NIR) biowindow are of significance for cancer phototheranostics. In this work, PtCu nanosheets with an average lateral size of less than 10 nm are synthesized as NIR photothermal and photoacoustic agents in vivo, which show strong light absorption from NIR-Ⅰ to NIR-Ⅱ biowindows with the photothermal conversion efficiencies of 20.4% under 808 nm laser and 32.7% under 1064 nm laser. PtCu nanosheets functionalized with folic acid-modified thiol-poly(ethylene glycol) (SH-PEG-FA) present good biocompatibility and 4T1 tumor-targeted effect, which give high-contrast photoacoustic imaging and efficient photothermal ablation of 4T1 tumor in both NIR-Ⅰ and NIR-Ⅱ biowindows. Our work significantly broadens applications of noble metal-based nanomaterials in the fields of cancer phototheranostics by rationally designing their structures and modulating their physicochemical properties.
Protein damage repair and prevention are important objectives in skin care industry. Skin protein damage or modifications such as glycation, carbonylation or oxidation, have a significant impact on its function, therefore directly influencing various skin functions or properties including skin appearance. However, there is a lack of comprehensive methods to visualize and assess the protein damage. In this article, we present a three-channel imaging approach to simultaneously visualize and quantitatively evaluate protein oxidation, protein glycation and carbonylation in a full-thickness skin model. We successfully visualized and quantified the impact of the multiple stimuli (ultraviolet radiation A (UVA) and/or methylglyoxal) as well as treatment effect of positive control (vitamins C and E) with this method. Our findings indicate that multiple stimuli exhibit synergistic effects on protein damage. Furthermore, we evaluated a unique combination of skin care ingredients which demonstrated an excellent efficacy in resisting protein damage. Further research revealed that three ingredients of the combination upregulate autophagy in cells, which may contribute to remove damaged proteins and maintain protein quality homeostasis. This method provides a holistic assessment of protein damages and can be employed to evaluate the impact of various stimuli or to assess the efficacy of skin care ingredients in mitigating such damage.
Conventional hydrometallurgy recycling process for treating wasted lithium-ion batteries (LIBs) typically results in the consumption of large amounts of corrosive leachates. Recent research on reusable leachate is expected to significantly improve the economic and environmental benefits, but is usually limited to specific and unique chemical reactions which could only apply to one type of metal elements. Herein, we report the co-extraction of multiple metal elements can be extracted without adding precipitates by mixed crystal co-precipitation, which enables the reusability of the leachate. We show that an oxalic acid (OA): choline chloride (ChCl): ethylene glycol (EG) type DES leachate system can leach transition metals from wasted LiNixCoyMn1-x-yO2 (NCM) cathode materials with satisfactory efficiency (The time required for complete leaching at 120 ℃ is 1.5 h). The transition metals were then efficiently extracted (with a recovery efficiency of over 96% for all elements) by directly adding water without precipitants. Noteworthy, the leachate can be efficiently recovered by directly evaporating the added water. The successful realization of reusability of leachate for the synergistic extraction of multiple elements relies on the regulation of the mixed crystal co-precipitation coefficient, which is realized by rationally design the reaction condition (composition of leachate, temperature and time) and induces the extraction of originally soluble manganese element. Our strategy is expected to be generally applicable and highly competent for industrial applications.
Even the sulfur cathode in lithium-sulfur (Li-S) battery has the advantages of high theoretical energy density, wide source of raw materials, no pollution to the environment, and so on. It still suffers the sore points of easy electrode collapse due to large volume expansion during charge and discharge and low active materials utilization caused by the severe shuttle effect of lithium polysulfides (LiPSs). Therefore, in this work, ramie gum (RG) was extracted from ramie fiber degumming liquid and used as the functional binder to address the above problems and improve the Li-S battery's performance for the first time. Surprisingly, the sulfur cathode using RG binder illustrates a high initial capacity of 1152.2 mAh/g, and a reversible capacity of 644.6 mAh/g after 500 cycles at 0.5 C, far better than the sulfur cathode using polyvinylidene fluoride (PVDF) and sodium carboxymethyl cellulose (CMC) binder. More importantly, even if the active materials loading increased to as high as 4.30 mg/cm2, the area capacity is still around 3.1 mAh/cm2 after 200 cycles. Such excellent performances could be attributed to the abundant oxygen- and nitrogen-containing functional groups of RG that can effectively inhibit the shuttle effect of LiPSs, as well as the excellent viscosity and mechanical properties that can maintain electrode integrity during long-term charging/discharging. This work verifies the feasibility of RG as an eco-friendly and high-performance Li-S battery binder and provides a new idea for the utilization of agricultural biomass resources.