The need for technological innovation in competitive sports is crucial for self-monitoring and smart decision making. In this work, we demonstrate how intelligent sports and smart decision making can be achieved in cricket and boxing using lithium-modified zinc titanium oxide (LZTO) nanofibers based on piezoelectric nanogenerators (PENGs) and triboelectric nanogenerators (TENGs). Zinc titanium oxide (ZTO) nanofibers synthesized using electrospinning followed by a calcination technique are modified with lithium to increase the output of the nanogenerator. An optimized PENG is fabricated using 25 wt % loading of LZTO (d 33 = 214 pm/V) in a poly(vinylidene fluoride) (PVDF) matrix as a double-layered structure and yields an open-circuit voltage (V oc) of 35 V and a short-circuit current (I sc) of 1.6 μA by manual tapping. To fabricate the TENG, Kapton and LZTO are used as negative and positive tribolayers, while Cu and adhesive polymer tape are used as the electrode and spacer, respectively. Furthermore, a hybrid nanogenerator (HNG) is fabricated by combining the PENG and TENG to produce a rectified voltage, current, and power density of up to 75 V, 3.2 μA, and 240 μW/cm2, respectively. These HNGs are integrated with a punching bag and demonstrated to differentiate among the six types of punches in boxing. Furthermore, PENGs are used in cricket to monitor the number of balls middled on the bat during practice and the contact of the ball with the bat and stumps for smart decision making. All kinds of lab-scale testing are done for these applications, which pave a way for exploring the frontiers in nanogenerator applications in sports as maintenance-free and self-powered sensing technology.

For high-energy-density supercapacitors, two-dimensional (2D) MXenes are being increasingly explored due to their inherent conductivity and excellent chemical properties. However, MXenes failed to achieve high power density and exceptional stability. Addressing this, we report the fabrication of an asymmetric supercapacitor with nickel MXene (cathode) and nitrogen (N), sulfur (S), and phosphorus (P) self-doped biomassderived activated carbon (anode). Detailed structural and chemical characterization studies reveal layered nanosheets in NiMX caused due to solvothermal etching cum exfoliation and unique micro− mesopore distribution in the optimized Euphorbia milii plant leafderived heteroatom self-doped activated carbon (EMAC-700) because of KOH activation. NiMX and EMAC-700 delivered high capacitances of 474.3 and 575.8 F/g, respectively, at 1 A/g with a 6 M KOH electrolyte. This is attributed to the pseudonature of NiMX and the presence of heteroatoms and the large surface area (2349 m 2 /g) of EMAC-700, facilitating fast electrolytic ion transfer. Finally, an asymmetric device with NiMX//EMAC configuration in 6 M KOH delivered a 152.6 F/g cell capacitance at 0.5 A/g under 0−1.5 V. Additionally, an ultrahigh energy density of 47.6 W h/kg at a 375 W/kg power density was achieved along with an 81.7% capacitance retention after 30,000 cycles at 15 A/g, signifying its potential for next-generation energy storage applications.

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