Deep-ultraviolet (DUV) photodetectors based on hexagonal boron nitride ( h-BN) have demonstrated great potentials for various commercial and military applications; however, to date, most studies show that the h-BN photodetectors suffer from poor performance, such as low responsivity and large dark current. Herein, we report the dramatic enhancement of photoresponse in the DUV region of a h-BN device coupled with plasmonic nanostructures of either h-BN nanosheets (BNNSs) or Au nanoparticles (NPs). Large-area h-BN thin films that have been directly grown on quartz substrates using the ion beam assistant deposition method exhibit a uniform thickness of ∼200 nm, an ultrawide bandgap (∼ 6 eV), and an excellent light transparency in the visible region. Based on the vertical charge transfer integrated with plasmonic nanoarrays, the photocurrent of the h-BN device can be greatly enhanced by up to about 7–9 times under the illumination of 205 nm by showing a cutoff wavelength at ∼220 nm. Owing to the retained low dark current and large photo-gain induced by localized plasmonic resonances, this hybrid photodetector exhibits 32- and 57-fold improvement in responsivity at a 205 nm wavelength by BNNSs and Au NPs, respectively. This work demonstrates plasmonic enhancement on optoelectronic properties of h-BN based on not only metallic but also semiconducting nanostructures and provides alternative pathways for the development of low-cost, large-area, high-performance, DUV photodetectors for various optoelectronic devices and security applications.

Silk fibroin materials are manufactured using printing and coating techniques at resolutions 1–2 µm. However, current processes are unstable, of low printability and versatility, and of limited feature size, and often require use of additives to process, which can impact material functionality and performance. Although there exist well established material synthesis and formulation approaches for making processable solutions from silkworm cocoons, these approaches do not translate to the emerging fabrication processes, such as aerosol jet printing (AJP). Here, a new approach is introduced to formulate silk‐worm solutions for AJP and subsequently analyze the processing limits, due to defects such as overspray, pooling, and cloudiness. It is found that the degumming step is critical and can lead to defects such as gelling and pooling. Furthermore, it is found that there exists a narrow processing window (sheath rate as a function of ink rate) for AJP formulations without defects. As with other materials (such as metal inks), overspray is an issue during the fabrication process; however, it is minimized within the processing window. This work stands to open a pathway for manufacturing new and emerging biodegradable materials suitable for pharmaceuticals, food packaging, and electronics, among others.

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