02330nas a2200241   4500008004100000022001400041245010300055210006900158260000800227300001100235490000700246520150900253653001701762653002801779653002401807653001401831653002601845653002601871100002501897700002001922700002101942856012501963       2026                        eng d  a1861-472800aFacile synthesis of fluoride-free mxene nanosheets as an efficient anode for lithium-ion capacitor0 aFacile synthesis of fluoridefree mxene nanosheets as an efficien  cJAN  ae705620 v213 a<p>
	MXenes are a promising class of two-dimensional (2D) nanomaterials known for their exceptional metallic conductivity and adjustable surface chemistry. However, the current state-of-the-art synthesis methods rely on the chemical etching of MAX phase (e.g., Ti3AlC2) with HF or fluoride-based compounds, leading to fluorine-terminated MXenes. These MXenes suffer from poor stability in ambient conditions, restricting their applications, particularly in lithium-ion-based batteries and capacitors (LIBs and LICs). In this study, we present a two-step method to produce fluorine-free MXene, addressing the stability issues of MXene in aqueous dispersions and relatively improved performance in LICs. Specifically, an efficient etching process employing hydroiodic acid (HI) with vinegar is used for the selective removal of the A layer from the MAX phase, resulting in F-free exfoliated MXenes (HVM). The HVM shows an outstanding electrical conductivity of 388 S cm(-1), maintaining high stability in aqueous dispersions over two weeks. HVM as electrode shows significantly enhanced Li+ ion storage capabilities, delivering a discharge capacity of 295 mAh g(-1) over 500 cycles at 1 A g(-1), substantially outperforming MXenes derived from F-based etching approaches. Furthermore, the HI-vinegar etching mechanism introduces unique surface functionalities that provide HVM superior cycling stability and rate capability, enabling more stable, high-performance MXene-based energy storage devices.</p>
10a2D materials10aElectrical conductivity10afluoride-free MXene10aHVM anode10aLithium-ion capacitor10alithium-ion diffusion1 aPawar, Meenakshi, D.1 aShinde, Dhanraj1 aShelke, Manjusha  uhttps://library.ncl.res.in/content/facile-synthesis-fluoride-free-mxene-nanosheets-efficient-anode-lithium-ion-capacitor02418nas a2200241   4500008004100000022001400041245010900055210006900164260000900233300001100242490000800253520160500261653002101866653002101887653002601908653001001934653002101944653001601965100002501981700002202006700002102028856012702049       2026                        eng d  a2352-152X00aMolecularly engineered PW12@Polypyrrole/MXene composite for high-energy, high-rate lithium-ion capacitor0 aMolecularly engineered PW12PolypyrroleMXene composite for highen  cFEB   a1201650 v1483 a<p>
	Due to inherent differences in the charge storage mechanisms of anode and cathode in a hybrid lithium-ion capacitor (LIC), a significant kinetic balance exists, necessitating the need to improve the ion/electron transfer capability of anode materials. In this study, we have developed a ternary pseudocapacitive composite comprising redox-active phosphotungstic acid nanoclusters (PW12) anchored to polypyrrole nanofibers (PPy), which are further decorated with Ti3C2Tx MXene (PW12@PPy/Ti3C2Tx) synthesized via an in-situ polymerization strategy. Here, Ti3C2Tx MXene serves as a conductive scaffold for PW12 wrapped PPy nanofibers, promoting efficient electron/ion transport. Simultaneously, the incorporation of PW12-anchored PPy nanofibers effectively mitigates the natural tendency of MXene to restack, thus preserving its layered structure. The PW12@PPy/Ti3C2Tx hybrid composite material delivers a high specific capacity of 767 mAh g-1 at 0.1 A g-1 after 100 cycles and a promising cycling stability of 280 mAh g-1 at 1 A g-1 up to 600 cycles. Moreover, an assembled LIC device using PW12@PPy/Ti3C2Tx as anode with nitrogen-doped sucrose carbon (NSC) as cathode demonstrates the highest energy density of 125 Wh kg-1 and maximum power density of 17,058 W kg-1. The device also maintains good cycling stability of 78.4 % capacity retention after 10,000 cycles at 1 A g-1. These results highlight a promising pathway for designing MXene-based hybrid composites with enhanced lithium storage performance, effectively addressing the kinetic mismatch challenges in LIC anode applications.</p>
10aFull cell device10aLi ion diffusion10aLithium-ion capacitor10aMXene10apolyoxometalates10apolypyrrole1 aPawar, Meenakshi, D.1 aPandey, Priyanshi1 aShelke, Manjusha  uhttps://library.ncl.res.in/content/molecularly-engineered-pw12polypyrrolemxene-composite-high-energy-high-rate-lithium-ion