Latest ArticlesAlthough lithium-ion batteries (LIBs) currently dominate a wide spectrum of energy storage applications, they face challenges such as fast cycle life decay and poor stability that hinder their further application. To address these limitations, element doping has emerged as a prevalent strategy to enhance the discharge capacity and extend the durability of Li-Ni-Co-Mn (LNCM) ternary compounds. This study utilized a machine learning-driven feature screening method to effectively pinpoint four key features crucially impacting the initial discharge capacity (IC) of Li-Ni-Co-Mn (LNCM) ternary cathode materials. These features were also proved highly predictive for the 50th cycle discharge capacity (EC). Additionally, the application of SHAP value analysis yielded an in-depth understanding of the interplay between these features and discharge performance. This insight offers valuable direction for future advancements in the development of LNCM cathode materials, effectively promoting this field toward greater efficiency and sustainability.
Industrial high-current-density oxygen evolution catalyst is the key to accelerating the practical application of hydrogen energy. Herein, Co9S8/CoS heterojunctions were rationally encapsulated in S, N-codoped carbon ((Co9S8/CoS)@SNC) microleaf arrays, which are rooted on S-doped carbonized wood fibers (SCWF). Benefiting from the synergistic electronic interactions on heterointerfaces and the accelerated mass transfer by array structure, the obtained self-supporting (Co9S8/CoS)@SNC/SCWF electrode exhibits superior performance toward alkaline oxygen evolution reaction (OER) with an ultra-low overpotential of 274 mV at 1000 mA/cm2, a small Tafel slope of 48.84 mV/dec, and ultralong stability up to 100 h. Theoretical calculations show that interfacing Co9S8 with CoS can upshift the d-band center of the Co atoms and strengthen the interactions with oxygen intermediates, thereby favoring OER performance. Furthermore, the (Co9S8/CoS)@SNC/SCWF electrode shows outstanding rechargeability and stable cycle life in aqueous Zn-air batteries with a peak power density of 201.3 mW/cm2, exceeding the commercial RuO2 and Pt/C hybrid catalysts. This work presents a promising strategy for the design of high-current-density OER electrocatalysts from sustainable wood fiber resources, thus promoting their practical applications in the field of electrochemical energy storage and conversion.
Mn-based P2-type oxides are considered as promising cathodes for Na-ion batteries; however, they face significant challenges, including structural degradation when charged at high cutoff voltages and structural changes upon storing in a humid atmosphere. In response to these issues, we have designed an oxide with co-doping of Cu and Al which can balance both cost and structural stability. The redox reaction of Cu2+/3+ can provide certain charge compensation, and the introduction of Al can further suppress the Jahn-Teller effect of Mn, thereby achieving superior long-term cycling performance. The ex-situ XRD testing indicates that Cu/Al co-doping can effectively suppress the phase transition of P2-O2 at high voltage, thereby explaining the improvement in electrochemical performance. DFT calculations reveal a high chemical tolerance to moisture, with lower adsorption energy for H2O compared to pure Na0.67Cu0.25Mn0.75O2. A representative Na0.67Cu0.20Al0.05Mn0.75O2 cathode demonstrates impressive reversible capacities of 148.7 mAh/g at 0.2 C, along with a remarkable capacity retention of 79.1% (2 C, 500 cycles).
Developing effective strategy for constructing the electrocatalysts enable tri-functional electrocatalytic activity of hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is the premise to achieve both the zinc-air battery (ZAB) and overall water splitting. Herein, we utilize density functional theory to calculate the cobalt nitride (CoxN, x = 1, 2, 4, 5.47) system, revealing that the Co5.47N maybe exhibits a tri-functional activity due to the diverse valence states and high-density d-electron state of Co site. Furthermore, the electron of Co site is further delocalized by the electronic compensation effect of vanadium nitride (VN), thus improving the intermediates absorption and electrocatalytic activity. Accordingly, the Co5.47N/VN heterojunction is designed and synthesized via an electrospinning and a subsequent pyrolysis route. As expected, it displays excellent HER, OER, and ORR activity in alkaline electrolyte, which can be applied to assemble ZAB with a high power density of 207 mW/cm2 and overall water splitting system only requires a lower voltage of 1.53 V to achieve 10 mA/cm2. The electron regulation effect of VN makes the Co valence state decrease in the reduction reaction whereas increase in the oxidization reaction as evidenced by quasi-operando XPS analyses. Importantly, two ZABs connected in series could drive overall water splitting, indicating the potential application in renewable energy technologies.
Green synthesis of drugs is of paramount importance for current public health and a prerequisite to new drugs exploiting. Nowadays, novel strategies of disease diagnosis and therapies are in blooming development as remarkable advances have been achieved which are all highly depended on drug development. Under the current requirements to high production capacity and novel synthesis methods of drugs, green synthesis based on strategies with different ways of empowering, advanced catalysts and unique reaction equipment are attracting huge attention and of great challenging. Higher quality products and environmentally friendly synthesis conditions are becoming more and more important for manufacturing process which has new requirements for catalyst materials and synthesis processes. Polyoxometalates (POMs) are class of transition metals-oxygen clusters with precise molecular structures and superior physicochemical properties which have made longstanding and important applications upon research community of functional materials, catalysis and medicine. In this review, the recent advances of polyoxometalates based strategies for green synthesis of drugs are summarized including POMs based catalysts, alternative reaction equipment based novel synthesis protocols. The significance of POMs to pharmaceutical and industrial field is highlighted and the related perspective for future development are well discussed.
Solid-state electrolytes (SSEs), as the core component within the next generation of key energy storage technologies - solid-state lithium batteries (SSLBs) - are significantly leading the development of future energy storage systems. Among the numerous types of SSEs, inorganic oxide garnet-structured superionic conductors Li7La3Zr2O12 (LLZO) crystallized with the cubic Ia3d space group have received considerable attention owing to their highly advantageous intrinsic properties encompassing reasonable lithium-ion conductivity, wide electrochemical voltage window, high shear modulus, and excellent chemical stability with electrodes. However, no SSEs possess all the properties necessary for SSLBs, thus both the ionic conductivity at room temperature and stability in ambient air regarding cubic garnet-based electrolytes are still subject to further improvement. Hence, this review comprehensively covers the nine key structural factors affecting the ion conductivity of garnet-based electrolytes comprising Li concentration, Li vacancy concentration, Li carrier concentration and mobility, Li occupancy at available sites, lattice constant, triangle bottleneck size, oxygen vacancy defects, and Li-O bonding interactions. Furthermore, the general illustration of structures and fundamental features being crucial to chemical stability is examined, including Li concentration, Li-site occupation behavior, and Li-O bonding interactions. Insights into the composition-structure-property relations among cubic garnet-based oxide ionic conductors from the perspective of their crystal structures, revealing the potential compatibility conflicts between ionic transportation and chemical stability resulting from Li-O bonding interactions. We believe that this review will lay the foundation for future reasonable structural design of oxide-based or even other types of superionic conductors, thus assisting in promoting the rapid development of alternative green and sustainable technologies.
Listeria monocytogenes (LM) is a dangerous foodborne pathogen for humans. One emerging and validated method of indirectly assessing LM in food is detecting 3-hydroxy-2-butanone (3H2B) gas. In this study, the synthesis of 3-(2-aminoethylamino) propyltrimethoxysilane (AAPTMS) functionalized hierarchical hollow TiO2 nanospheres was achieved via precise controlling of solvothermal reaction temperature and post-grafting route. The sensors based on as-prepared materials exhibited excellent sensitivity (480 Hz@50 ppm), low detection limit (100 ppb), and outstanding selectivity. Moreover, the evaluation of LM with high sensitivity and specificity was achieved using the sensors. Such stable three-dimensional spheres, whose distinctive hierarchical and hollow nanostructure simultaneously improved both sensitivity and response/recovery speed dramatically, were spontaneously assembled by nanosheets. Meanwhile, the moderate loadings of AAPTMS significantly improved the selectivity of sensors. Then, the gas-sensing mechanism was explored by utilizing thermodynamic investigation, Gaussian 16 software, and in situ diffuse reflectance infrared transform spectroscopy, illustrating the weak chemisorption between the -NH- group and 3H2B molecules. These portable sensors are promising for real-time assessment of LM at room temperature, which will make a magnificent contribution to food safety.
Efficient electrocatalysts for oxygen reduction reaction (ORR) show significant importance for advancing the performance and affordability of proton exchange membrane fuel cells and other energy conversion devices. Herein, PtCo3 nanoalloys dispersed on a carbon black support, were prepared using ultrafast Joule heating method. By tuning the heating modes, such as high-temperature shock and heating for 2 s, two kinds of PtCo3 nanoalloys with varying crystallinities were obtained, referred to as PtCo3HTS (average size of 5.4 nm) and PtCo3HT-2 s (average size of 6.4 nm), respectively. Impressively, PtCo3HTS exhibited superior electrocatalytic ORR activity and stability (E1/2 = 0.897 V vs. RHE and 36 mV negative shift after 50, 000 cycles), outperforming PtCo3HT-2 s (E1/2 = 0.872 V and 16.2 mV negative shift), as well as the commercial Pt/C (20 wt%) catalyst (E1/2 = 0.847 V and 21.0 mV negative shift). The enhanced ORR performance of PtCo3HTS may be attributed to its low crystallinity, which results in an active local electronic structure and chemical state, as confirmed by X-ray diffraction (XRD) and X-ray absorption fine structure (XAFS) analyses. The ultrafast Joule heating method showed great potential for crystallinity engineering, offering a promising pathway to revolutionize the manufacturing of cost-effective and environmentally friendly catalysts for clean energy applications.
Photodynamic therapy (PDT) has emerged as a promising approach for tumor treatment due to its non-invasiveness and high selectivity. However, the off-target activation of phototoxicity and the limited availability of tumor-specific biomarkers pose challenges for effective PDT. Here, we present the development of a novel ratiometric near-infrared-Ⅱ (NIR-Ⅱ) fluorescent organic nanoprobe, BTz-IC@IR1061, which responds specifically to hypochlorite (HClO) within tumors. This nanoprobe allows ratiometric fluorescence imaging to monitor and guide activated tumor PDT. BTz-IC@IR1061 nanoparticles were synthesized by codoping the small molecule dye BTz-IC, which generates reactive oxygen species (ROS), with the commercial dye IR1061. The presence of HClO selectively activates the fluorescence and photodynamic properties of BTz-IC while destroying IR1061, enabling controlled release of ROS for tumor therapy. We demonstrated the high selectivity of the nanoprobe for HClO, as well as its excellent photostability, photoacoustic imaging capability, and photothermal effects. Furthermore, in vivo studies revealed effective tumor targeting and remarkable tumor growth inhibition through tumor-activated PDT. Our findings highlight the potential of BTz-IC@IR1061 as a promising tool for tumor-specific PDT, providing new opportunities for precise and controlled cancer therapy.
Shape control of nickel sulfide (NiS2) catalysts is beneficial for boosting their catalytic performances, which is vital to their practical application as a class of advanced non-noble electro-catalysts. However, precisely controlling the formation kinetics and fabricate ultrathin NiS2 nanostructures still remains challenge. Herein, we provide an injection rate-mediated method to fabricate ultrathin NiS2 nanocages (HNCs) with hierarchical walls, high-density lattice defects and abundant grain boundaries (GBs). Through mechanism analysis, we find the injection rate determines the concentration of S2− in the steady state and thus control the growth pattern, leading to the formation of NiS2 HNCs at slow etching kinetics and NiCo PBA@NiS2 frames at fast etching kinetics, respectively. Benefiting from the ultrathin and hierarchical walls that minimize the mass transport restrictions, the high-density lattice defects and GBs that offer abundant unsaturated reaction sites, the NiS2 HNCs exhibit obviously enhanced electrocatalytic activity and stability toward OER, with overpotential of 255 mV to reach 10 mA/cm2 and a Tafel slope of 27.44 mV/dec, surpassing the performances of NiCo PBA@NiS2 frames and commercial RuO2.