Readily commercializable and cost-effective next-generation CsPbBr perovskite nanocrystals (PNCs) based X-ray detectors are demonstrated. The PNCs-based X-ray detector exhibits higher spatial resolution (9.8 lp mm at modulation transfer function (MTF) = 0.2 and 12.5-8.9 lp mm for a linear line chart), faster response time (≈200 ns), and comparable stability (>40 Gy s of X-ray exposure) compared with the commercialized terbium-doped gadolinium oxysulfide (GOS)-based detectors (spatial resolution = 6.2 lp mm at MTF = 0.2 and 6.3 lp mm for a linear line chart, response time = ≈1200 ns) because the PNCs-based scintillator has ≈5.6-fold faster average photoluminescence lifetime and stronger emission than the GOS-based one.

Intensive studies have recently been performed on graphene-based photodetectors, but most of them are based on field effect transistor structures containing mechanically exfoliated graphene, not suitable for practical large-scale device applications. Here we report highefficient photodetector behaviours of chemical vapor deposition grown all-graphene p-n vertical-type tunnelling diodes. The observed photodetector characteristics well follow what are expected from its band structure and the tunnelling of current through the interlayer between the metallic p-and n-graphene layers. High detectivity (B10 12 cm Hz 1/2 W À 1 ) and responsivity (0.4B1.0 A W À 1 ) are achieved in the broad spectral range from ultraviolet to near-infrared and the photoresponse is almost consistent under 6-month operations. The high photodetector performance of the graphene p-n vertical diodes can be understood by the high photocurrent gain and the carrier multiplication arising from impact ionization in graphene.

Super-flexible bis(trifluoromethanesulfonyl)-amide (TFSA)-doped graphene transparent conducting electrode (GR TCE)-based FAPbI3 − xBrx perovskite solar cells with 18.9% power conversion efficiency (PCE) for a rigid device and 18.3% for a flexible one are demonstrated because the TFSA-doped GR TCE reveals high conductivity and high transmittance.

We report substantially enhanced photoluminescence (PL) from hybrid structures of graphene/ZnO films at a band gap energy of ZnO (∼3.3  eV/376  nm). Despite the well-known constant optical conductivity of graphene in the visible-frequency regime, its abnormally strong absorption in the violet-frequency region has recently been reported. In this Letter, we demonstrate that the resonant excitation of graphene plasmon is responsible for such absorption and eventually contributes to enhanced photoemission from structures of graphene/ZnO films when the corrugation of the ZnO surface modulates photons emitted from ZnO to fulfill the dispersion relation of graphene plasmon. These arguments are strongly supported by PL enhancements depending on the spacer thickness, measurement temperature, and annealing temperature, and the micro-PL mapping images obtained from separate graphene layers on ZnO films.

Super flexible TCO-free FAPbI3−xBrx planar type inverted perovskite solar cells with a 17.9% power conversion efficiency under 1 sun conditions were demonstrated by introducing an APTES (3-aminopropyl triethoxysilane) adhesion promoter between a PET flexible substrate and a AuCl3-doped single-layer graphene transparent electrode.