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Due to the advanced properties of layered 2D materials, their heterostructuring with conventional 3D semiconductors is one of the promising ways to design efficient and affordable optoelectronic devices. However, systematic studies on designing 2D/3D heterojunctions with a focus on enhancing the photodetection properties are sparse in the literature. In this report, we present systematic experimental and theoretical investigations on 2D MoS2/MoSe2 heterostructuring with modified GaN substrates for designing efficient photodetectors. We achieved a gradual increment in photocurrent by engineering MoS2 and MoSe2 as single/double heterojunctions on GaN substrates. Time-correlated single-photon counting (TCSPC) results infer significant improvement in the lifetimes of the photoexcited charge carriers for the optimized MoS2/MoSe2/e-GaN heterostructure-based photodetectors. Interestingly, photodetectors designed with double heterojunctions that maintain type-II band alignment (e-GaN/MoSe2/MoS2) exhibit the highest photoresponsivity of 82 A/W, specific detectivity of 1.79 ×1014 Jones, external quantum efficiency of 27,880%, and stability for over 6 months in a laboratory testing environment under the illumination of 365 nm. Density functional theory (DFT) simulations establish the superiority of double heterojunctions with staircase band alignment for efficient charge carrier transport. This study provides fundamental insights on optimizing the band alignment for desired photodetection concerning 2D/3D integration, which can be exploited for other hybrid integrated systems and applications. [ABSTRACT FROM AUTHOR]

Numerous structures have been reported in search of affordable self-powered broadband photodetectors, however with limited success. The hybrid perovskite heterostructures have been attracted great attention due to their advance optical and electrical properties. The stability and facile synthesis are critical issues in achieving the potential success of realizing perovskite-based photodetectors. Herein, we report a facile one-step spray-coated method to synthesize MAPbI3 perovskite polycrystalline thin-film on the glass as photodetector followed by their morphological (Atomic force microscopy), structural (X-ray diffraction/Fourier transform infrared spectroscopy, optical (UV–Vis), and electrical characterization. The device shows a very good response for visible and NIR region with the responsivity, detectivity, and external quantum efficiency of 1.682 mA/W, 1.5065 × 1012 Jones, and 0.3799, respectively. Further, the device exhibits photoresponse under visible to IR (400–900 nm) light illuminations, which holds great futuristic promises for affordable, broadband, stable, and efficient energy-conserving electronics. [ABSTRACT FROM AUTHOR]

Conventional chemical approaches for synthesizing nanoparticles (NPs) may restrict their applicability as they are not eco‐friendly, energetically efficient and often involve toxic reducing/capping agents; but phytonanotechnology enabled the synthesis of safe, inexpensive, highly biocompatible NPs. In this regard, thorough understanding of green components and the modulatory effects of different reaction conditions on the physicochemical parameters of green synthesized NPs would be a prerequisite, which is not depicted elsewhere. This review critically analyzes the relevant reaction conditions from their mechanistic viewpoints in plant‐based synthesis of NPs arising fundamental issues which need to be determined carefully. The size, stability and surface chemistry of phytogenic NPs may be fabricated as a function of multiple interconnected reaction parameters and the plant species used. The therapeutic potential of phytogenic NPs may depend on the plant species used; and so the meticulous understanding of physicochemical parameters and the family wise shorting of elite plant species may potentially benefit the theranostic future of plant‐based NPs. [ABSTRACT FROM AUTHOR]

Tin-based TMDCs are gaining traction in optoelectronics due to their eco-friendliness and easy synthesis, contrasting Mo/W-based counterparts. This study pioneers the solvothermal synthesis of highly crystalline SnSSe alloy, akin to Janus structures, bridging a notable research gap. By integrating SnS 2 /SnSSe materials onto a GaN platform, a synergistic heterojunction is created, enhancing light absorption and the electron-hole pair separation efficiency, demonstrating a self-powered photodetection. The GaN/SnS 2 /SnSSe heterojunction showcases a staircase-like (type-II) band alignment and exceptional performance metrics: high photoresponsivity of 314.96 A W -1 , specific detectivity of 2.0 × 10 14 jones, and external quantum efficiency of 10.7 × 10 4 % under 365 nm illumination at 150 nW cm -2 intensity and 3 V bias. Notably, the device displays intensity-dependent photocurrent and photoswitching behaviors without external bias, highlighting its unique self-powered attributes. This study underscores SnS 2 's significance in optoelectronics and explores SnSSe integration into van der Waals heterostructures, promising advanced photodetection devices and bias-free optoelectronics.

Broadband photodetection including deep UV using Si is technically challenging due to its negligible optical absorption at 254 nm and the requirement of heterogeneous integration with very high bandgap photoactive materials. However, monolithic integration of high-bandgap semiconductors on Si is not possible due to CMOS fabrication incompatibility. Comprehensive experimental studies to achieve broadband photodetection including deep UV on Si are lacking in the literature. Here for the first time we have investigated 2D/0D heterojunctions of WS 2 /WO 3 on a Si platform both experimentally and theoretically and established the charge transfer mechanism between them. Transient photocarrier decay experiments demonstrate effective quenching of excited photocarriers generated in WO 3 /WS 2 , signifying its utility in facilitating carrier transport, which is further evidenced by charge density calculation from DFT simulation. Our designed vertically aligned p -Si/WS 2 /WO 3 heterojunction-based photodetector exhibits an excellent photosensitivity performance with a broad spectral response ranging from deep ultraviolet (254 nm) to near infrared (940 nm) wavelengths, and it not only provides a peak responsivity of 251 A W -1 and a specific detectivity of 1.89 × 0 14 Jones, but also possesses a rapid response speed with a rise/fall time of 0.64/0.48 s at 365 nm with a bias of 2 volt.