Ternary boron carbon nitride (BCN) semiconductors have been developed as emerging metal-free photocatalysts for visiblelight reduction of CO 2 , but the achieved efficiency is still not satisfying. Herein, we report that the CO 2 photoreduction performance of a bulk BCN semiconductor can be substantially improved by surface engineering with CdS nanoparticles. The CdS/BCN photocatalysts are characterized completely by diverse tests (e.g., XRD, FTIR, XPS, DRS, SEM, TEM, N 2 sorption, PL, and transient photocurrent spectroscopy). Performance of the CdS/BCN heterostructures is evaluated by reductive CO 2 conversion reactions with visible light under benign reaction conditions. Compared with bare BCN material, the optimized CdS/BCN photocatalyst exhibits a 10-fold-enhanced CO 2 reduction activity and high stability, delivering a considerable CO production rate of 12.5 μmol h −1 (250 μmol h −1 g −1 ) with triethanolamine (TEOA) as the reducing agent. The reinforced photocatalytic CO 2 reduction activity is mainly assigned to the obviously improved visible-light harvesting and the greatly accelerated separation/transport kinetics of light-triggered electron−hole pairs. Furthermore, a possible visible-light-induced CO 2 reduction mechanism is proposed on the basis of photocatalytic and photo(electro)chemical results.

Engineering of the optical, electronic, and magnetic properties of hexagonal boron nitride (h-BN) nanomaterials via oxygen doping and functionalization has been envisaged in theory. However, it is still unclear as to what extent these properties can be altered using such methodology because of the lack of significant experimental progress and systematic theoretical investigations. Therefore, here, comprehensive theoretical predictions verified by solid experimental confirmations are provided, which unambiguously answer this long-standing question. Narrowing of the optical bandgap in h-BN nanosheets (from ≈5.5 eV down to 2.1 eV) and the appearance of paramagnetism and photoluminescence (of both Stokes and anti-Stokes types) in them after oxygen doping and functionalization are discussed. These results are highly valuable for further advances in semiconducting nanoscale electronics, optoelectronics, and spintronics.

Halide perovskites are an emerging scintillator material for X-ray imaging. High-quality X-ray imaging generally requires high spatial resolution and long operation lifetime, especially for targeted objects with irregular shapes. Herein, a perovskite "polymer-ceramics" scintillator, in which the halide perovskite nanocrystals are grown inside a pre-solidified polymer structure with high viscosity (6 × 10 12 cP), is designed to construct flexible and refreshable X-ray imaging. A nucleation inhibition strategy is proposed to prevent the agglomeration and Ostwald ripening of perovskite crystals during the subsequent precipitation process, enabling a high-quality polymer-ceramics scintillator with high transparency. This scintillator-based detector achieves a detection limit of 120 nGy s -1 and a spatial resolution of 12.5 lp mm -1 . Interestingly, due to the anchoring effect of the exfoliated atoms provided by the polymer matrix, the scintillator film can be refreshed after a long duration (≥3 h) and high dose (8 mGy s -1 ) irradiation. More importantly, this inherent characteristic overcomes the long operation lifetime issue of perovskites-based scintillators. Hence, the authors' exploration of the polymer-ceramics scintillator paves the way for the development of flexible and durable perovskite scintillators that can be produced at a low operation cost.

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Solvated electrons have attracted increasing research interest due to their strong reducing ability. However, the generation and utilization of solvated electrons in photocatalytic systems are rarely reported owing to the challenges in synthesis and their complex structures. Here, we present a photocatalytic system by accessing laboratory-scale concentrations of ammoniated electrons. Under visible light irradiation, ammoniated electrons are achieved by a cyanamide functionalized and potassium heptazine based melon polymer (PC-HM) in the presence of an electron donor, which are stable for days. This PC-HM can produce ammoniated electrons at room temperature to reduce dioxygen, thus enabling the production of H 2 O 2 coupled with the selective oxidation of alcohols under visible light illumination. This work presents the possibility to take advantage of ammoniated electrons for solar energy conversion in energy and advanced organic chemistry.