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It is a challenging task to fabricate thermally stable Photodetectors (PDs) working in visible light spectrum range due to the degradation in photoresponse characteristics. Herein, excellent performance parameters with photoresponsivity reached up to as high as 50 AW -1 , and ultrahigh specific detectivity in excess of 2.3×10 12 Jones have been obtained simultaneously in a single photodetector based on vertical MoS 2 (v-MoS 2 ) at a high temperature of 200°C. The TiO 2 interlay layer is ascribed as the main factor to enhance the PDs performances by reducing lattice mismatch between v-MoS 2 and substrate, separating photogenerated electron-hole pairs (EHPs), and the formation of the vertical MoS 2 nanostructures. Besides, the optoelectronics performances of the v-MoS 2 /TiO 2 heterostructures based field-effect transistor (FET) have also been examined under various operating temperatures, and the mechanism on how gate voltages affect the PDs performances has also been studied. In a word, the present fabricated v-MoS 2 /TiO 2 heterostructures based FET PDs will find practical applications in high-temperature environment. 

Perovskites have been firmly established as one of the most promising materials for third-generation solar cells. There remain several great and lingering challenges to be addressed regarding device efficiency and stability. The photovoltaic efficiency of perovskite solar cells (PSCs) depends drastically on the charge-carrier dynamics. This complex process includes charge-carrier generation, extraction, transport and collection, each of which needs to be modulated in a favorable manner to achieve high performance. Two-dimensional materials (TDMs) including graphene and its derivatives, transition metal dichalcogenides ( e.g. , MoS 2 , WS 2 ), black phosphorus (BP), metal nanosheets and two-dimensional (2D) perovskite active layers have attracted much attention for application in perovskite solar cells due to their high carrier mobility and tunable work function properties which greatly impact the charge carrier dynamics of PSCs. To date, significant advances have been achieved in the field of TDM-based PSCs. In this review, the recent progress in the development and application of TDMs ( i.e. , graphene, graphdiyne, transition metal dichalcogenides, BP, and others) as electrodes, hole transporting layers, electron transporting layers and buffer layers in PSCs is detailed. 2D perovskites as active absorber materials in PSCs are also summarized. The effect of TDMs and 2D perovskites on the charge carrier dynamics of PSCs is discussed to provide a comprehensive understanding of their optoelectronic processes. The challenges facing the PSC devices are emphasized with corresponding solutions to these problems provided with the overall goal of improving the efficiency and stability of photovoltaic devices. 

2D black phosphorene (BP) carries a stellar set of physical properties such as conveniently tunable bandgap and extremely high ambipolar carrier mobility for optoelectronic devices. Herein, the judicious design and positioning of BP with tailored thickness as dual‐functional nanomaterials to concurrently enhance carrier extraction at both electron transport layer/perovskite and perovskite/hole transport layer interfaces for high‐efficiency and stable perovskite solar cells is reported. The synergy of favorable band energy alignment and concerted cascade interfacial carrier extraction, rendered by concurrent positioning of BP, delivered a progressively enhanced power conversion efficiency of 19.83% from 16.95% (BP‐free). Investigation into interfacial engineering further reveals enhanced light absorption and reduced trap density for improved photovoltaic performance with BP incorporation. This work demonstrates the appealing characteristic of rational implementation of BP as dual‐functional transport material for a diversity of optoelectronic devices, including photodetectors, sensors, light‐emitting diodes, etc.

 

Ever‐developing energy storage technologies demand the pursuit of advanced materials with multiple functionalities. Recent studies revealed that multiple heteroatom‐doped carbon has been wildly used for bi‐functional or even tri‐functional energy storage and conversion. However, few efforts have been made to uncover the origin of multi‐functionalities. Herein, a nitrogen, phosphorus, and sulfur tri‐doped carbon is designed in this work with large porosity, rich heteroatoms doping and high mass density, exhibiting excellent bifunctionalities on supercapacitors and oxygen reduction reaction. Importantly, the density functional theory calculations demonstrate the relevant co‐doping and tri‐doping generate more active sites on neighboring carbon atoms than single doping, and the same type of active sites may enhance bifunctionalities simultaneously. The present investigations provide a promising guidance on the design of multi‐functional materials for future energy storage and conversion applications.

 

Although tremendous efforts have been devoted to understanding the origin of boosted charge storage on heteroatom‐doped carbons, none of the present studies has shown a whole landscape. Herein, by both experimental evidence and theoretical simulation, it is demonstrated that heteroatom doping not only results in a broadened operating voltage, but also successfully promotes the specific capacitance in aqueous supercapacitors. In particular, the electrolyte cations adsorbed on heteroatom‐doped carbon can effectively inhibit hydrogen evolution reaction, a key step of water decomposition during the charging process, which broadens the voltage window of aqueous electrolytes even beyond the thermodynamic limit of water (1.23 V). Furthermore, the reduced adsorption energy of heteroatom‐doped carbon consequently leads to more stored cations on the heteroatom‐doped carbon surface, thus yielding a boosted charge storage performance.

 

Although tremendous efforts have been devoted to understanding the origin of boosted charge storage on heteroatom‐doped carbons, none of the present studies has shown a whole landscape. Herein, by both experimental evidence and theoretical simulation, it is demonstrated that heteroatom doping not only results in a broadened operating voltage, but also successfully promotes the specific capacitance in aqueous supercapacitors. In particular, the electrolyte cations adsorbed on heteroatom‐doped carbon can effectively inhibit hydrogen evolution reaction, a key step of water decomposition during the charging process, which broadens the voltage window of aqueous electrolytes even beyond the thermodynamic limit of water (1.23 V). Furthermore, the reduced adsorption energy of heteroatom‐doped carbon consequently leads to more stored cations on the heteroatom‐doped carbon surface, thus yielding a boosted charge storage performance.