Triboelectric nanogenerator (TENG) devices have gotten great attention in wearable power sources and physiological monitoring. However, the complicated assembling and the molding processing retard their applications. Here, 3D-printed TENGs (3DP-TENGs) are designed and readily fabricated by a single integrated process without additional assembling steps. The TENGs contain poly(glycerol sebacate) (PGS) and carbon nanotubes (CNTs) as the two electrification components. Conductive CNTs also serve as electrodes. Elastic PGS matrix makes TENGs intrinsically responsive to biomechanical motions leading to robust energy outputs. The hierarchical porous structure of the 3DP-TENG results in higher output efficiency than traditional molded microporous TENG counterparts. TENGs with different 3D shapes are readily fabricated for different applications. The 3DP-TENG insole efficiently harvests biomechanical energy to drive electronics. A ring-shaped TENG acts as a self-powered sensor to monitor the motion of fingers. Furthermore, the use of bio-based and biodegradable PGS matrix combining with efficient recycle of CNTs makes 3DP-TENGs favorable from sustainable perspective. This work provides a new strategy to design and tailor 3D TENGs that will be very useful for diverse electronic applications.

Three-dimensional (3D) printing thermosets offers great potential to customize sophisticated constructs for a myriad of applications.

Self-powered information encoding devices (IEDs) have drawn considerable interest owing to their capability to process information without batteries. Next-generation IEDs should be reprogrammable, self-healing, and wearable to satisfy the emerging requirements for multifunctional IEDs; however, such devices have not been demonstrated. Herein, an integrated triboelectric nanogenerator-based IED with the aforementioned features was developed based on the designed light-responsive high-permittivity poly­(sebacoyl diglyceride-co-4,4′-azodibenzoyl diglyceride) elastomer (PSeDAE) with a triple-shape-memory effect. The electrical memory feature was achieved through a microscale shape-memory property, enabling spatiotemporal information reprogramming for the IED. Macroscale shape-memory behavior afforded the IED shape-reprogramming ability, yielding wearable and detachable features. The dynamic transesterifications and light-heating groups in the PSeDAE afforded a remotely controlled rearrangement of its cross-linking network, producing the self-healing IED.

In article number https://doi.org/10.1002/adfm.201805108, Zhengwei You and co‐workers report a simple and versatile 3D‐printing strategy to efficiently fabricate a triboelectric nanogenerator (3DP‐TENG) with an unique hierarchical porous structure, excellent elasticity, and superior energy output. 3DP‐TENGs with diverse 3D shapes are readily tailored to act as wearable energy harvesters and self‐powered sensors. The biobased, biodegradable, and biocompatiable matrix makes 3DP‐TENGs eco‐friendly and sustainable.

Three-dimensional (3D) printing has had a large impact on various fields, with fused deposition modeling (FDM) being the most versatile and cost-effective 3D printing technology. However, FDM often requires sacrificial support structures, which significantly complicates the processing and increase the cost. Furthermore, poor layer-to-layer adhesion greatly affects the mechanical stability of 3D-printed objects. Here, we present a new Print-Healing strategy to address the aforementioned challenges. A polymer ink (Cu-DOU-CPU) with synergetic triple dynamic bonds was developed to have excellent printability and room-temperature self-healing ability. Objects with various shapes were printed using a simple compact 3D printer, and readily assembled into large sophisticated architectures via self-healing. Triple dynamic bonds induce strong binding between layers. Additionally, damaged printed objects can spontaneously heal, which significantly elongates their service life. This work paves a simple and powerful way to solve the key bottlenecks in FDM 3D printing, and will have diverse applications.

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In order to study the influence factors of steel sheet surface waviness in cold rolling process, using coherence scanning interferometry, the surface waviness with different cold rolling processes had been investigated at room temperature, and without condensation according to relevant standard. The results show that the surface waviness of the typical steel was successfully evaluated, while the mill reduction rate, working roll cycle, and temper rolling elongation were found to be the most informative for surface waviness parameters Wa0.8 and Wsa1-5 It was found that the surface waviness parameters Wa0.8 and Wsa1-5 sharply increased with increasing rolling reduction rates in rolling process, and vice versa. Moreover, in the continuous annealing process, finish rolling temperature had almost no effect on the waviness. In temper rolling, the surface waviness parameters Wa0.8 and Wsa1-5 gradually increased with elongation and dropped with increasing working roll period. Ultimately, it was proved that the control measures to improve the surface waviness of steel plate in cold rolling process successfully improved the product surface quality.