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Bio‐inspired and biodegradable quantum optics scenarios constitute a pathway toward environmentally friendly front‐end technologies. Such an inspiring perspective necessitates the replacement of classic gain materials with a biological counterpart like photoluminescent bacteria. It is easy to imagine that, in this case, a planar and cell‐viable substitute of classic bulk solid‐states resonators can be highly beneficial. In this paper a micro‐ and nano‐photonic structuration of both a standard and a functionalized version of a typical bacterial growth medium (Luria‐Bertani Agar – LBA) is successfully realized. Three structures belonging to the categories of photonic crystals are replicated, such as quasi‐crystals and meta‐surfaces, demonstrating how the proposed media can be used as templates for high‐end photonic applications. The optical quality of the replicated structures is confirmed by far‐field diffraction measurements. The structured growth media allow for a broad control of the surface wettability by accessing a so‐called Wenzel state, in which the original hydrophilicity of a material is increased due to the photonic structuration. Finally, the suitability of the nano‐structured LBA as a plasmonic platform is evidenced. The proposed micro‐and nano‐structured photonic growth media constitute the first, fundamental step toward quantum optical frameworks from biological media. [ABSTRACT FROM AUTHOR]

The materials commonly used to fabricate thermoelectric devices are tellurium, lead, and germanium. These materials ensure the best thermoelectric performance, but exhibit drawbacks in terms of availability, sustainability, cost, and manufacturing complexity. Moreover, they do not guarantee a safe and cheap implementation in wearable thermoelectric applications. Here, p‐Type and n‐type flexible thermoelectric textiles are produced with sustainable and low‐cost materials through green and scalable processes. Cotton is functionalized with inks made with biopolyester and carbon nanomaterials. Depending on the nanofiller, i.e., graphene nanoplatelets, carbon nanotubes, or carbon nanofibers, positive or negative Seebeck coefficient values are obtained, resulting in a remarkable electrical conductivity value of 55 S cm−1 using carbon nanotubes. The best bending and washing stability are registered for the carbon nanofiber‐based biocomposites, which increase their electrical resistance by 5 times after repeated bending cycles and only by 30% after washing. Finally, in‐plane flexible thermoelectric generators coupling the best p‐ and n‐type materials are fabricated and analysed, resulting in an output voltage of ≈1.65 mV and a maximum output power of ≈1.0 nW by connecting only 2 p/n thermocouples at a temperature difference of 70 °C. [ABSTRACT FROM AUTHOR]

Developing multi‐functional green conductive materials is instrumental in reducing electronic waste. In article 1800069, Pietro Cataldi, Ilker S. Bayer and co‐workers use crop ingredients and graphene to produce flexible conductors using the bio‐advantaged approach. The conductive nanocomposite can be regarded as "plant‐e‐tronics" with promising applications such as electromagnetic interference shielding, wireless antennas and photovoltaics. [ABSTRACT FROM AUTHOR]

In today's fast‐paced and well‐connected world, consumer electronics are evolving rapidly. As a result, the amount of discarded electronic devices is becoming a major health and environmental concern. The rapid expansion of flexible electronics has the potential to transform consumer electronic devices from rigid phones and tablets to robust wearable devices. This means increased use of plastics in consumer electronics and the potential to generate more persistent plastic waste for the environment. Hence, today, the need for flexible biodegradable electronics is at the forefront of minimizing the mounting pile of global electronic waste. A "bioadvantaged" approach to develop a biodegradable, flexible, and application‐adaptable electronic components based on crop components and graphene is reported. More specifically, by combining zein, a corn‐derived protein, and aleuritic acid, a major monomer of tomato cuticles and sheellac, along with graphene, biocomposite conductors having low electrical resistance (≈10 Ω sq−1) with exceptional mechanical and fatigue resilience are fabricated. Further, a number of high‐performance electronic applications, such as THz electromagnetic shielding, flexible GHz antenna construction, and flexible solar cell electrode, are demonstrated. Excellent performance results are measured from each application comparable to conventional nondegrading counterparts, thus paving the way for the concept of "plant‐e‐tronics" towards sustainability. Sustainable materials for consumer electronics are imperative to address the ever‐increasing e‐waste problem. Here a simple bioadvantaged plant electronics material is shown by direct mixing/polymerization of crop proteins monomers in the presence of graphene to create various flexible plant‐e‐tronics applications such as wireless antennas, electromagnetic interference shielding, and photovoltaics. [ABSTRACT FROM AUTHOR]