High-Performance Chlorophyll-b/Si Nanowire Heterostructure for Self-Biasing Bioinorganic Hybrid Photodetectors

Abstract

As one kind of ecofriendly organic semiconductor materials, chlorophyll has attracted great attention with useful optical properties. Although pigments such as chlorophyll-a (Chl-a) are explored widely, chlorophyll-b (Chl-b) is rarely studied even though it possesses outstanding optical properties with impressive stability. Here, Chl-b is extracted from spinach leaves using a very simple and cost-effective method to study its potential use on Si nanowire (NW) heterostructures having volume concentration varying from 0 to 6%. In comparison to the control Si NW device, the Chl-b/SiNW heterostructure exhibits superior optoelectronic performances including high on/off ratio (∼10 3 ), good external quantum efficiency (∼208%), high responsivity (∼0.73 A/W), improved detectivity (∼2.2 × 10 12 Jones), and relatively faster response time (<1 s) under 435 nm illumination. In addition, it offers quite promising values of the abovementioned figure of merits of a photodetector over the wide spectral range from 350−1100 nm. This low-cost and high-sensitivity Chl-b/SiNW heterostructure device thus opens up challenging research possibilities for green energy conversion and biophotonic applications on Si-compatible complementary metal−oxide−semiconductor platforms.

Self-Powered Photodetector Fabricated from a Single-Charge-Transfer Complex Nanowire Grown In Situ between Prefabricated Electrodes on an Si3N4 Membrane

“…Due to the existence of surface states, minority carriers are either trapped or transit slowly, whereas majority carriers have a faster transit time across the device, as stated above. This causes transport of a large number of majority carriers across the junction by injecting extra electrons from the opposite electrode to maintain the charge neutrality before a minority carrier reaches the other electrode or recombines in the device interior . This gives a high photocurrent in the outer circuit per incident photon and thus, a high external efficiency, exceeding 100%.…”

“…This causes transport of a large number of majority carriers across the junction by injecting extra electrons from the opposite electrode to maintain the charge neutrality before a minority carrier reaches the other electrode or recombines in the device interior. 41 This gives a high photocurrent in the outer circuit per incident photon and thus, a high external efficiency, exceeding 100%.…”

Bilayer chlorophyll-based bio-photodetector based on Z-type charge transfer process

“…9 Although the versatile properties of Chl have led to a series of investigations of Chl and its derivatives in solar energy conversion and storage devices, the related study of Chl in photodetectors is still very preliminary. [10][11][12][13][14][15][16][17][18][19] In our study, a new bilayer Chl bio-photo-detector was prepared by a Chl solution process and Z-scheme was introduced into the bio-photodetector. The Z-type biophotodetector consists of two photoinduced electron separation steps, namely, photosystem I (PSI) and photosystem II (PSII), and an electron transfer chain connecting the two optical systems.…”

Self-Powered Photodetector Based on Ag/CH3NH3PbI3/C Asymmetric Dual-Terminal Device

“…The development of self-powered or self-driven photodetectors holds significance in energy-saving systems as they operate independently of external power sources. − Extensive research studies have been conducted on self-powered photodetectors based on semiconductor materials, such as perovskite CsPbI x Br 3‑x , , TiO 2 , ZnO, − GaN, and graphene, − demonstrating superior optoelectronic performance. However, most existing self-powered photodetectors rely on complex p – n structures, making the achievement of self-powered photodetection with a simple structure even more profound. − …”