luminescence, and also the recent hologram technique. [1-3] Compared to other conventional techniques, the fluorescence printing patterns supply promising high security to the key information valuable documents due to the tunable emission properties. [4,5] As counterfeiting technology has also been quickly developed, the traditional mono-mode anti-counterfeiting is far from the requirement of practical applications to guarantee a high level of data and information safety. The traditional anti-counterfeiting luminescence is achieved by the mono-mode downshifting (DS) luminescence, which converts the high energy photon into lower energy luminescence. To address such concern, developing more complicated anti-counterfeiting techniques by increasing the luminescent modes becomes the most challenging topic. Presently, the realization of concurrent upconversion (UC) and DS have been successfully utilized in anti-counterfeiting based on the lanthanide-based dopants. [6-9] The Eu-doped down-shift luminescent materials have been applied in the Euro banknotes, which enables the visible photoluminescence (PL) based on UV lamp excitation. Meanwhile, the Bank of China also introduced the Yb/Er-doped UC phosphors in the banknotes as the counterfeiting technique, which emits the Anti-counterfeiting techniques have become a global topic since they is correlated to the information and data safety, in which multimodal luminescence is one of the most desirable candidates for practical applications. However, it is a long-standing challenge to actualize robust multimodal luminescence with high thermal stability and humid resistance. Conventionally, the multimodal luminescence is usually achieved by the combination of upconversion and downshifting luminescence, which only responds to the electromagnetic waves in a limited range. Herein, the Yb 3+ /Er 3+ /Bi 3+ co-doped Cs 2 Ag 0.6 Na 0.4 InCl 6 perovskite material is reported as an efficient multimodal luminescence material. Beyond the excitation of ultraviolet light and nearinfrared laser (980 nm), this work extends multimodal luminescence to the excitation of X-ray. Besides the flexible excitation sources, this material also shows the exceptional luminescence performance, in which the X-ray detection limit reaches the level of nGy s −1 , indicating a great potential for further application as a colorless pigment in the anti-counterfeiting field. More importantly, the obtained double perovskite features high stability against both humidity and temperature up to 400 °C. This integrated multifunctional luminescent material provides a new directional solution for the development of multifunctional optical materials and devices.

Low doses (< 1 cGy) of 60 kVp X-rays protect HeLa x skin fibroblast human hybrid cells against neoplastic transformation in vitro.

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The charge transfer phenomenon of contact electrification even exists in the liquid–solid interface by a tiny droplet on the solid surface. In this work, we have investigated the contact electrification mechanism at the liquid–solid interface from the electronic structures at the atomic level. The electronic structures display stronger modulations by the outmost shell charge transfer via surface electrostatic charge perturbation than the inter-bonding-orbital charge transfer at the liquid–solid interface, supporting more factors being involved in charge transfer via contact electrification. Meanwhile, we introduce the electrochemical cell model to quantify the charge transfer based on the pinning factor to linearly correlate the charge transfer and the electronic structures. The pinning factor exhibits a more direct visualization of the charge transfer at the liquid–solid interface. This work supplies critical guidance for describing, quantifying, and modulating the contact electrification induced charge transfer systems in triboelectric nanogenerators in future works.

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