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[Display omitted] • The photoresponsive microcapsules were prepared via a one-step method. • The coordination polymer assembled to form nanofibers at the interface. • The nanofibers, as emulsifiers, exhibited a Janus structure. • The microcapsules can be used as photocontrolled microreactors. In recent decades, stimuli-responsive microcapsules have attracted increasing attention due to their potential applications as microreactors for drug delivery, catalytic reactions, etc.; however, the complicated preparation process and the difficulty of size fixation and recycling need to be addressed. In this work, we developed a one-step preparation method to fabricate photoresponsive microcapsules based on the interfacial self-assembly of an azopyridine coordination polymer. The coordination of silver ions and ligands was performed in situ at an oil–water interface, and the coordination polymer self-assembled into nanofibers, which stabilized the Pickering emulsion and produced water-in-oil microcapsules. Additionally, microcapsules with a uniform size were prepared based on a microfluidic process. Both the crystal structure and the Janus surface of nanofibers were determined to elucidate the mechanism of self-assembly and interface stabilization. When the microcapsules were irradiated with 365 nm UV light, the cis isomerization of the azo group in the coordination polymer led to the disassembly and dissolution of the nanofibers, resulting in fusion of the microcapsules and demulsification of the Pickering emulsion. Conversely, visible light and heating triggered the trans isomerization of the azopyridine coordination polymer and thus caused regeneration of the nanofibers and recovery of the microcapsules. Finally, microcapsules encapsulating several reactants were employed in the pH-indicator discoloration reaction and the enzyme-catalyzed decomposition of H 2 O 2 to demonstrate their feasibility as photocontrolled microreactors. This kind of photoresponsive microcapsule with one-step preparation and good recyclability might have potential applications in the field of microreactors. [ABSTRACT FROM AUTHOR]

[Display omitted] • CM-CNT/graphene electrode was directly constructed by core-sheath 3D printing. • Electrode features hierarchical pores and highly interconnected conductive network. • Electrode enables adequate channel and pathway for ultrafast ion/electron transport. • Pseudocapacitor exhibits prominent stability and electrochemical performance. Pseudocapacitance holds great promise for energy density improvement of supercapacitors. However, how to enable a pseudocapacitor with combined feature of high mass loading of pseudocapacitive material, efficient ion/electron transport, as well as facile and scalable manufacturing, still remains a significant challenge. Herein, we demonstrated an efficient and scalable extrusion-based core-sheath 3D printing strategy for directly and controllably constructing pseudocapacitive carbon nanotube (CNT)- MoS 2 (CM)-CNT/graphene electrode, with high mass loading up to 55% and uniform distribution of MoS 2 , hierarchically porous configuration and highly interconnected conductive network framework built by coupling graphene scaffold located in shell layer and CNTs situated in core layer. The unique architecture featuring adequate channels and pathways can act as a "superhighway" for ultrafast ion diffusion and electron transport throughout the entire device, thereby enabling fast kinetics of Faradaic reactions and abundant availability of electrochemical active sites. A symmetric pseudocapacitor assembled with 3D-printed electrode and in situ electrospun poly(vinylidene fluoride) (PVDF) nanofiber separator delivered high specific capacitance (558 mF cm−2) and energy density (49 µWh cm−2), remarkable cycling stability (87% after 8000 cycles), and superior capacity even at large electrode thickness. This work has shed light on new strategies for designing and fabricating high-performance pseudocapacitors toward future uses. [ABSTRACT FROM AUTHOR]