Robust and Elastic Bioinspired MXene‐Coated Foams with Enhanced Energy Storage and Conversion Capabilities

• Published in: Advanced materials technologies Vol. 8; no. 8
• Main Authors: Jiang, Degang, Bacal, Christine Jurene O., Usman, Ken Aldren S., Zhang, Jizhen, Qin, Si, Hegh, Dylan, Lei, Weiwei, Liu, Jingquan, Razal, Joselito M.
• Format: Journal Article
• Language: English
• Published: 24.04.2023
• Subjects: compressible supercapacitors; elastic foams; MXene foams; PEI/PDA coatings; steam generation
• ISSN: 2365-709X; 2365-709X
• DOI: 10.1002/admt.202201611

Constructing highly porous structures using Ti3C2Tx MXene provides a promising strategy toward achieving low density, high specific surface area, and shorter ion/molecule transport paths. However, the weak MXene‐MXene or MXene‐substrate interactions hinder the development of ultra‐robust and elastic MXene‐based architectures. To address this issue, a bio‐inspired strategy is developed to effectively adhere the MXene nanosheets onto melamine foam via covalent and hydrogen bonding interactions through polyethyleneimine/polydopamine‐modification. The enhanced interactions contribute to high MXene loading (≈94 wt.%) and reversible compressibility even after 10 000 compression/release cycles at 80% strain. The compressible supercapacitor device assembled from this foam exhibits high energy storage capability (119 F g−1 at 2 mV s−1) with capacitance retention of ≈93% after 1000 compression/release cycles at 50% strain. Moreover, the presence of polydopamine and MXene enable the absorption of light in the UV–Vis and near‐IR regions, respectively, inducing photothermal conversion functionality, with an evaporation rate of ≈1.5 kg m−2 h−1 and ≈89% solar evaporation efficiency under one sun illumination. It is envisaged that this bio‐inspired chemical modification offers a versatile strategy for the assembly of MXene nanosheets onto different substrates for various applications, such as electromagnetic interference shielding, energy storage, and conversion. An ultra‐robust and elastic MXene based foam is fabricated by using a facial and bioinspired template strategy, which demonstrates high MXene loading (≈93.6 wt.%) and reversible compressibility even after 10 000 compression/release cycles at high strain of 80%. Given these superior attributes, the as‐prepared foam can be used for compressible supercapacitors or steam generation applications.