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P-doped g-C3N4 has been successfully synthesized using hexachlorocyclotriphosphazene, a low cost and environmentally benign compound, as phosphorus source, and guanidiniumhydrochloride as g-C3N4 precursor, via a thermally induced copolymerization route.

While stretchable micro‐supercapacitors (MSCs) have been realized, they have suffered from limited areal electrochemical performance, thus greatly restricting their practical electronic application. Herein, a facile strategy of 3D printing and unidirectional freezing of a pseudoplastic nanocomposite gel composed of Ti3C2Tx MXene nanosheets, manganese dioxide nanowire, silver nanowires, and fullerene to construct intrinsically stretchable MSCs with thick and honeycomb‐like porous interdigitated electrodes is introduced. The unique architecture utilizes thick electrodes and a 3D porous conductive scaffold in conjunction with interacting material properties to achieve higher loading of active materials, larger interfacial area, and faster ion transport for significantly improved areal energy and power density. Moreover, the oriented cellular scaffold with fullerene‐induced slippage cell wall structure prompts the printed electrode to withstand large deformations without breaking or exhibiting obvious performance degradation. When imbued with a polymer gel electrolyte, the 3D‐printed MSC achieves an unprecedented areal capacitance of 216.2 mF cm−2 at a scan rate of 10 mV s−1, and remains stable when stretched up to 50% and after 1000 stretch/release cycles. This intrinsically stretchable MSC also exhibits high rate capability and outstanding areal energy density of 19.2 µWh cm−2 and power density of 58.3 mW cm−2, outperforming all reported stretchable MSCs.

Skin-mountable and transparent devices are highly desired for next-generation electronic applications but are susceptible to unexpected ruptures or undesired scratches, which can drastically reduce the device lifetime. Developing wearable and transparent materials with healable function that can recover their original functionality after mechanical damage under mild and noninvasive repairing operation is thus imperative. Herein, we demonstrate that the incorporation of ultrasmall quantities of plasmonic silver nanoparticle (AgNP)@MXene nanosheet hybrids to serve as photothermal fillers in waterborne elastic polyurethane enables high transparency as well as effective light-triggered healing capabilities for wearable composite coatings. The AgNP@MXene hybrid functions as a highly effective photon captor, energy transformer, and molecular heater due to the amalgamation of (1) ultrahigh photothermal conversion efficiency, high thermal conductivity, and structural properties of MXene, (2) the outstanding plasmonic effect of AgNPs, and (3) the synergistic effects from their hybrids. The resulting wearable composite coating with ultralow loading of plasmonic AgNP@MXene hybrids (0.08 wt % or 0.024 vol %) can produce a significant temperature increase of ∼111 ± 2.6 °C after the application of 600 mW cm–2 light irradiation for 5 min, while maintaining a high optical transmittance of ∼83% at a thickness of ∼60 μm. This local temperature increase can rapidly heal the mechanical damage to the composite coating, with a healing efficiency above 97%.

The construction of intramolecular donor-acceptor conjugated copolymers have been devised for years to enhance the mobility of charge carriers in organic photovoltaic field, however surprisingly, similar strategies have not been reported in polymeric photocatalytic systems for promoting the separation of charge carriers. Graphitic carbon nitride (g-C 3 N 4 ) is an emerging polymeric visible-light photocatalyst with high stability but still low photocatalytic efficiency. Here we prepared a series of g-C 3 N 4 -based intramolecular donor-acceptor copolymers, i.e., aromatics-incorporated g-C 3 N 4 , via nucleophilic substitution/addition reactions.The copolymer showed remarkably enhanced and stable visible-light photocatalytic hydrogen evolution performance. The intramolecular charge transfer transition is firstly proposed to explain the photocatalytic activity of g-C 3 N 4 -baed photocatalysts under long wavelength-light irradiation.

A solar-thermal water evaporation structure that can continuously generate clean water with high efficiency and good salt rejection ability under sunlight is highly desirable for water desalination, but its realization remains challenging. Here, a hierarchical solar-absorbing architecture is designed and fabricated, which comprises a 3D MXene microporous skeleton with vertically aligned MXene nanosheets, decorated with vertical arrays of metalorganic framework-derived 2D carbon nanoplates embedded with cobalt nano particles. The rational integration of three categories of photothermal materials enables broadband light absorption, efficient light to heat conversion, low heat loss, rapid water transportation behavior, and much-improved corrosion and oxidation resistance. Moreover, when assembling with a hydrophobic insulating layer with hydrophilic channel, the MXene-based solar absorber can exhibit effective inhibition of salt crystallization due to the ability to advect and diffuse concentrated salt back into the water. As a result, when irradiating under one sun, the solar-vapor conversion efficiency of the MXene-based hierarchical design can achieve up to ≈93.4%, and can remain over 91% over 100 h to generate clean vapor for stable and continuous water desalination. This strategy opens an avenue for the development of MXenebased solar absorbers for sustainable solar-driven desalination.

Graphite-C3N4/Bi2WO6 composites with enhanced response to visible light and remarkably enhanced selective CO2 photoreduction to CO were synthesized and demonstrated to be promising photocatalysts for CO2 photoconversion.

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