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2D conductive metal–organic frameworks (2D c‐MOFs) naturally possess high active sites, large specific surface areas, and fast ion transport for energy‐storage devices. However, the intelligent exploration of 2D c‐MOFs for the emerging flexible transparent supercapacitors (FTSCs) with excellent photoelectric property and electrochemical activity is rarely implemented. Herein, 2D conductive ultrathin Cu3(HHTP)2 (HHTP = 2,3,6,7,10,11‐hexahydroxytriphenylene) film is synthesized on the indium tin oxide/polyethylene terephthalate (ITO/PET) substrate for flexible transparent conductive electrodes (FTCEs) through the layer‐by‐layer assembly method. The interconnected conductive frameworks possess the cooperative superiority of low internal resistance, fast electrolyte ion diffusion, and quick electron transfer. Cu3(HHTP)2‐15/ITO/PET FTCEs show high photoelectric property of T550 nm = 82.2% and Rs = 49.1 Ω sq−1, and high areal capacitance (CA) of 1700 µF cm−2. The corresponding symmetrical FTSCs (T550 nm = 62.1%) exhibit excellent CA of 939.2 µF cm−2 at the current density of 7 µA cm−2, superior rate capability (63.9% at 150 µA cm−2), long‐term cycling stability (85% after 3000 cycles), and mechanical flexibility under different bending angles. This work provides key insights into the design and synthesis of 2D c‐MOF films for flexible transparent energy‐storage devices.

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provides the accurate and real-time external information for machine. [9] The materials of flexible sensor should comply with the following criteria: i) excellent flexibility to match human tissue, ii) high and stable conductivity to rapidly and reliably respond the signals, iii) tight adhesion to human body surface, iv) safety and nontoxic to contact with the human body. Hydrogel is a kind of highly hydrophilic 3D network gel, which are like human tissues in structure and composition. [10] For example, our research group has prepared a 3D porous cellulose hydrogel to realize a highly sensitive flexible strain sensor. [11] Tao et al. fabricated a micropyramid-patterned double-network ionic organ hydrogels for flexible sensor to detect subtle pressure changes. [12] They are desirable to satisfy the requirement of flexible sensor by the unique properties including flexibility, extreme precision, high durability, and skin-friendliness by the adjusted structure and components. At present, it is limited to the development of a single function in wearable HMI electronics. However, it is still a challenge to develop multifunction hydrogel with excellent properties for high-precision flexible strain sensor to achieve precise control in wearable HMI electronics.The personal thermal management (PTM) technology provides specific temperature control and health monitoring for various novel interactive ways of wearable HMI electronics, and effectively improve practicality and user experience. [13,14] As one of the representative categories, photothermal conversion technology converts light energy into thermal energy by reflection and absorption, which conforms to the concept of energy saving and has been applied in PTM technology. [15,16] Nowadays, flexible hydrogels with excellent photothermal property have been obtained by introducing photothermal conversion agents (i.e., carbon nanomaterials, [17] organic materials, [18] metal materials, [19] and semiconductor materials [20] ) into the matrix.As a new type of 2D transition metal carbides and nitrides, MXene has exhibited prominent photothermal conversion performance due to the profits from high light absorption and the localized surface plasmon resonance (LSPR) effect. [21,22] Accordingly, MXene hydrogel is one of the suitable candidates for flexible photothermal materials, which can be used in the Wearable human-machine interaction (HMI) is an advanced technology that realizes operations, collaborations, and interactions between human and machines in a co-located or coordinated way. As the core component of wearable HMI electronics, the flexible sensor is desirable to be intelligent, accurate, collaborative, and multifunctional for the feedback control. Here, the multifunctional MXene/polyacrylic acid (PAA) hydrogel is prepared by radical polymerization. As a flexible strain sensor, it exhibits high sensitivity (gauge factor ≈4.94), wide detection range (0-1081%) and stable signal output for 500 cycles. It can also monitor human movement and operate manipulator in real tim...