Surface passivated halide perovskite single-crystal for efficient photoelectrochemical synthesis of dimethoxydihydrofuran

Abstract

Halide perovskite single-crystals have recently been widely highlighted to possess high light harvesting capability and superior charge transport behaviour, which further enable their attractive performance in photovoltaics. However, their application in photoelectrochemical cells has not yet been reported. Here, a methylammonium lead bromide MAPbBr3 single-crystal thin film is reported as a photoanode with potential application in photoelectrochemical organic synthesis, 2,5-dimethoxy-2,5-dihydrofuran. Depositing an ultrathin Al2O3 layer is found to effectively passivate perovskite surface defects. Thus, the nearly 5-fold increase in photoelectrochemical performance with the saturated current being increased from 1.2 to 5.5 mA cm−2 is mainly attributed to suppressed trap-assisted recombination for MAPbBr3 single-crystal thin film/Al2O3. In addition, Ti3+-species-rich titanium deposition has been introduced not only as a protective film but also as a catalytic layer to further advance performance and stability. As an encouraging result, the photoelectrochemical performance and stability of MAPbBr3 single-crystal thin film/Al2O3/Ti-based photoanode have been significantly improved for 6 h continuous dimethoxydihydrofuran evolution test with a high Faraday efficiency of 93%.

Limits to Electrical Mobility in Lead-Halide Perovskite Semiconductors

“… 1 , 13 MHP single crystals have attracted intense interest because of their potential in fabricating photodetectors, 14 X-ray scintillators and detectors, 15 − 17 as well as applications in photocatalysis and photoelectrochemical fields. 18 On the other hand, the cutting-edge photovoltaic devices have been mostly developed on a platform of polycrystalline thin films because of their ease of fabrication. While such thin films have shown remarkable performance in solar cells, the question remains as to what the upper limit of performance might be for perfectly crystalline thin-film devices and whether this transition is required to further expand the applications of MHP into areas such as optical communications that require semiconductor devices including optical transmitters, modulators, and detectors with high switching speeds.…”

Metal Halide Perovskites for Solar Fuel Production and Photoreactions

“…Therefore, further stabilization strategies, such as composition engineering and It is reasonable to conclude that MHPs are promising candidates for heterogeneous photocatalyst materials for visible light utilization, and growing attention has been placed on the photocatalytic application of MHPs. 27 There has been much progress in less than 5 years since the first report of the photocatalytic utilization of MHPs. In the following sections, we will discuss several recent developments for each specific photocatalytic reaction.…”

“…Recently, Kuang's group reported a photoelectrochemical system for 2,5-dimethoxy-2,5-dihydrofuran synthesis. 27 They encapsulated a single-crystal CH 3 NH 3 PbBr 3 thin film with Al 2 O 3 to stabilize the MHP photoanode in an acetonitrile/methanol mixed electrolyte and utilized bromine as a redox mediator (Br − /Br + ) for the oxidation of furan to 2,5-dimethoxy-2,5-dihydrofuran synthesis. This interesting approach can be extended to diverse halogen-mediated organic syntheses using MHP photocatalysts.…”

“…Therefore, further stabilization strategies, such as composition engineering and encapsulation of MHPs, are important for prolonged operation. Very recently, in February 2021, Kuang’s group photoelectrochemically synthesized 2,5-dimethoxy-2,5-dihydrofuran by encapsulating the surface of a (CH 3 NH 3 )­PbBr 3 thin film with Al 2 O 3 . There has been much progress in less than 5 years since the first report of the photocatalytic utilization of MHPs.…”

“…All redox potentials are referenced to the normal hydrogen electrode (NHE). Data obtained from refs − , − , and − and references therein.…”