2D/3D Perovskite Photodetectors with High Response Frequency and Improved Stability Based on Thiophene-2-ethylamine and Dual Additives.

Organic-inorganic lead halide perovskite materials have received great attention in recent years. However, the poor stability of these materials severely limits the commercial application of perovskite devices. Here, we used thiophene-2-ethylammonium iodide (TEAI) material as the organic spacer NHSCN and NHCl as the dual additives to realize high-stability two-dimensional (2D)/three-dimensional (3D) perovskite thin films for perovskite photodetectors.

Accelerating Photogenerated Hole Tunneling through Passivation Layers Reducing Interplanar Spacing for Efficient and Stable Perovskite Solar Cells.

Interfacial passivation engineering plays a crucial role in the explosive development of perovskite solar cells (PSCs). However, previous studies on passivation layers mainly focused on the defect-passivation mechanism rather than the interfacial charge transport efficiency. Here, by precisely tuning the interplanar spacing of the ammonium iodide passivation layer, we elucidate the promoting effect of the reduced interplanar spacing of the passivation layer on the photogenerated hole tunneling efficiency at the interface of the hole transport layer and perovskite.

MAPbI Photodetectors with 4.7 MHz Bandwidth and Their Application in Organic Optocouplers.

The photodetector based on methylammonium lead iodide (MAPbI) is a promising device for wide wavelength range (380-780 nm) sensitivity. However, its industrial application is limited by the relatively low response speed to the light signal, which has received little attention. Only a few reports show low-bandwidth characteristics (less than 1 MHz at 0.

Efficient Planar Perovskite Solar Cells with Carbon Quantum Dot-Modified spiro-MeOTAD as a Composite Hole Transport Layer.

In perovskite solar cells (PSCs), the hole-transport layer (HTL) plays an essential role in effective charge transport and extraction from the photoexcited perovskite, thus being significant for overall power conversion efficiency (PCE) and operational stability. So far, spiro-MeOTAD has been the most widely used HTL despite its inherent drawbacks, such as highly hygroscopic nature, poor conductivity, and mismatched energy-level alignment with the perovskite active layer. Here, a spiro-MeOTAD-based composite HTL modified by microwave method-synthesized carbon quantum dots (CQDs) was proposed and demonstrated as a promising HTL candidate for high-performance PSCs.

Interpenetrating interfaces for efficient perovskite solar cells with high operational stability and mechanical robustness.

The perovskite solar cell has emerged rapidly in the field of photovoltaics as it combines the merits of low cost, high efficiency, and excellent mechanical flexibility for versatile applications. However, there are significant concerns regarding its operational stability and mechanical robustness. Most of the previously reported approaches to address these concerns entail separate engineering of perovskite and charge-transporting layers.

Enhancing the Interface Contact of Stacking Perovskite Solar Cells with Hexamethylenediammonium Diiodide-Modified PEDOT:PSS as an Electrode.

As an indispensable component of perovskite solar cells (PSCs), the commonly used Au and Ag electrodes still have some problems such as high cost and instability issues with regard to being corroded by iodide ions. In this paper, we report stacking perovskite solar cells (S-PSCs), which can avoid the use of precious metal electrodes and reduce the cost of devices and the requirements of equipment compared to conventional PSCs. The S-PSCs are composed of two semicells: a photoanode and a counter electrode (CE).

Ozone-Mediated Controllable Hydrolysis for a High-Quality Amorphous NbO Electron Transport Layer in Efficient Perovskite Solar Cells.

Amorphous NbO electron transport layer (ETL) shows great potential for boosting the power conversion efficiency (PCE) of perovskite solar cells (PSCs) at low temperatures (<100 °C). To date, it is still a challenge to simultaneously control the hydrolysis of the NbO precursor solution and reduce the impurities of NbO ETLs during low-temperature solution processing under ambient conditions. Herein, for the first time, we report ozone (O) as a strong ligand to stabilize Nb salt solutions under ambient conditions.

Efficient and stable emission of warm-white light from lead-free halide double perovskites.

Lighting accounts for one-fifth of global electricity consumption. Single materials with efficient and stable white-light emission are ideal for lighting applications, but photon emission covering the entire visible spectrum is difficult to achieve using a single material. Metal halide perovskites have outstanding emission properties; however, the best-performing materials of this type contain lead and have unsatisfactory stability.

Hole-Conductor-Free, Metal-Electrode-Free TiO2/CH3NH3PbI3 Heterojunction Solar Cells Based on a Low-Temperature Carbon Electrode.

Low cost, high efficiency, and stability are straightforward research challenges in the development of organic-inorganic perovskite solar cells. Organolead halide is unstable at high temperatures or in some solvents. The direct preparation of a carbon layer on top becomes difficult.

Low-Temperature and Solution-Processed Amorphous WO(x) as Electron-Selective Layer for Perovskite Solar Cells.

The electron-selective layer (ESL) is an indispensable component of perovskite solar cells (PSCs) and is responsible for the collection of photogenerated electrons. Preparing ESL at a low temperature is significant for future fabrication of flexible PSCs. In this work, solution-processed amorphous WO(x) thin film was prepared facilely at low temperature and used as ESL in PSCs.

Selenium as a photoabsorber for inorganic-organic hybrid solar cells.

As an inorganic photoabsorber, selenium was used in a mesoscopic solar cell with a hybrid organic-inorganic structure of TiO2/Se/P3HT/PEDOT:PSS/Ag, in which the Se layer was prepared by vacuum thermal deposition and post thermal treatment. The microstructure, photoelectrical properties, as well as the rationality in structural design of the solar cell were illustrated in detail. Finally, the hybrid solar cell demonstrated a photoelectric conversion efficiency of 2.