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The wide range of pressure detection and the exceptional linearity are essential performance parameters for flexible pressure sensors, enabling them to adapt to diverse scenarios and acquire information accurately. However, currently available "ultra‐wide range" piezoresistive sensors lack an optimal solution that effectively balances sensing properties, device thickness, and process cost. This study proposes a distinctive approach by introducing a Janus conductive structure assembled with dual resistive sensitive layers. The design allows for a pressure‐induced staged transformation of the current transport path, effectively mitigating variations and saturation in sensor resistance over a wide pressure range. The resulting piezoresistive sensor demonstrates an unprecedented detection range of 0–3800 kPa, showcasing remarkable sensitivity of 4.11 kPa−1 and outstanding linearity of 99.9% within the range of 0–1000 kPa. Additionally, the sensor boasts a thickness of only ≈200 µm, made possible through the utilization of a cellulose nanofibers material matrix. These performance achievements stand at the forefront when compared to existing reports. This research explores the potential applications of these sensors and extended arrays in the domains of human health and motion monitoring. It investigates their utility in gait analysis for assisted posture correction, as well as in the assessment and rehabilitation of gait instability. [ABSTRACT FROM AUTHOR]

Lignin‐carbohydrate complexes (LCC) underpin the comprehensive properties of natural wood. Facile restoration of LCC analogues in paper is challenging because of the charge repulsion between negatively charged lignin and pulp fibrils. A camouflage strategy is discovered to prepare positively charged lignosulfonate–polyamide‐epichlorohydrin complex (LPC) nanoparticles, which are effectively incorporated in pulp through the "LPC–pulp" attraction instead of "lignosulfonate–pulp" repulsion. Water‐resistant LPC paper sheets are prepared in ≈20 min without pressurization. They exhibit high tensile strength (41 MPa), surviving boiling water treatment for 14 days, on par with the strength of pristine paper and certain plastics in a dry state. The camouflage strategy applies to various pulps and processing technologies, as exemplified by a paper separator showing exceptional electrolyte wettability and rate capability in lithium‐ion batteries. This work establishes advanced cellulose valorization with combined strength, water stability, and tailored microstructures replacing petroleum polymers in engineering and energy implications. [ABSTRACT FROM AUTHOR]

Flexible broadband photodetectors based on 2D MoS2 have gained significant attention due to their superior light absorption and increased light sensitivity. However, pristine MoS2 has absorption only in visible and near IR spectrum. This paper reports a paper-based broadband photodetector having ZnS-MoS2 hybrids as active sensing material fabricated using a simple, cost effective two-step hydrothermal method wherein trilayer MoS2 is grown on cellulose paper followed by the growth of ZnS on MoS2. Optimization in terms of process parameters is done to yield uniform trilayer MoS2 on cellulose paper. UV sensing property of ZnS and broadband absorption of MoS2 in visible and IR, broadens the range from UV to near IR. ZnS plays the dual role for absorption in UV and in the generation of local electric fields, thereby increasing the sensitivity of the sensor. The fabricated photodetector exhibits a higher responsivity toward the visible light when compared to UV and IR light. Detailed studies in terms of energy band diagram are presented to understand the charge transport mechanism. This represents the first demonstration of a paper-based flexible broadband photodetector with excellent photoresponsivity and high bending capability that can be used for wearable electronics, flexible security, and surveillance systems, etc. [ABSTRACT FROM AUTHOR]

Cellulose paper (CP)-based asymmetrical thin film supercapacitors (ATFSCs) have been considered to be a novel platform for inexpensive and portable devices as the CP is low-cost, lightweight, and can be rolled or folded into 3D configurations. However, the low energy density and poor cycle stability are serious bottlenecks for the development of CP-based ATFSCs. Here, sandwich-structured graphite/Ni/Co2NiO4-CP is developed as positive electrode and the graphite/Ni/AC-CP as negative electrode for flexible and high-performance ATFSCs. The fabricated graphite/Ni/Co2NiO4-CP positive electrode shows a superior areal capacitance (734 mF/cm2 at 5 mV/s) and excellent cycling performance with ≈97.6% Csp retention after 15 000 cycles. The fabricated graphite/Ni/AC-CP negative electrode also exhibits large areal capacitance (180 mF/cm2 at 5 mV/s) and excellent cycling performance with ≈98% Csp retention after 15 000 cycles. The assembled ATFSCs based on the sandwich-structured graphite/Ni/Co2NiO4-CP as positive electrode and graphite/Ni/AC-CP as negative electrode exhibit large volumetric Csp (7.6 F/cm3 at 5 mV/s), high volumetric energy density (2.48 mWh/cm3, 80 Wh/kg), high volumetric power density (0.79 W/cm3, 25.6 kW/kg) and excellent cycle stability (less 4% Csp loss after 20 000 cycles). This study shows an important breakthrough in the design and fabrication of high-performance and flexible CP-based electrodes and ATFSCs. [ABSTRACT FROM AUTHOR]