Regulations currently in force enable to claim that the lead content in perovskite solar cells is low enough to be safe, or no more dangerous, than other electronics also containing lead. However, the actual environmental impact of lead from perovskite is unknown. Here we show that the lead from perovskite leaking into the ground can enter plants, and consequently the food cycle, ten times more effectively than other lead contaminants already present as the result of the human activities. We further demonstrate that replacing lead with tin represents an environmentally-safer option. Our data suggest that we need to treat the lead from perovskite with exceptional care. In particular, we point out that the safety level for lead content in perovskite-based needs to be lower than other lead-containing electronics. We encourage replacing lead completely with more inert metals to deliver safe perovskite technologies.

In view of the increasing concerns for environmental problems caused by the widespread use of antibiotics, there is an urgent demand to develop effective technologies for antibiotics removal from pharmaceutical wastewater. For this purpose, photocatalysis has been developed as an important advanced oxidation technology possessing remarkable prospective, and thus, the semiconductor photocatalysts are currently attracting unprecedented research attention. Herein, we report the fabrication of composite materials based on nitrogen-doped carbons and cadmium sulfide semiconductors (CdS/NC–T ) derived solely from cadmium metal–organic frameworks (Cd–MOF) through a facile in situ carbonization method, as well as their application as viable photocatalysts toward tetracycline degradation under visible irradiation. It was revealed that cadmium and sulfur species in Cd–MOF precursors assembled to form CdS nanoparticles (NPs), which were deposited simultaneously on nitrogen-doped carbon scaffolds to afford CdS/NC–T composites during carbonization processes. PXRD and TEM studies on as-prepared CdS/NC–T materials indicated the formation of crystalline hexagonal (Wurtzite) CdS NPs on carbonaceous supports. These CdS/NC–T composites were further studied for photocatalytic tetracycline degradation in aqueous solutions under visible irradiation, among which CdS/NC–500 exhibited the highest TC degradation efficiency of ca. 83% within 1 h. It was found that the photocatalytic performance of CdS/NC–T depended largely on carbonization temperature, which suggested great potentials of the proposed synthetic pathway in engineering of new visible-light-driven photocatalysts.

A conjugated microporous polymer (CMP) material was designed with pore function of cyano and pyridyl groups that act as potential binding sites for Ag ion capture. Ultrafine silver nanoparticles (less than 5 nm) were successfully supported on the predesigned CMP material to afford Ag@CMP composite materials by means of a simple liquid impregnation and light-induced reduction method. Spherical Ag nanoparticles with a statistical mean diameter of ca. 3.9 nm were observed and characterized by scanning electron microscopy and transmission electron microscopy. The Ag@CMP composite materials were consequently exploited as high-performance nanocatalysts for the reduction of nitrophenols, a family of priority pollutants, at various temperatures and ambient pressure. Moreover, the composite nanocatalysts feature convenient recovery and excellent reusability. This work presents an efficient platform to achieve ultrafine metal nanoparticles immobilized on porous supports with predominant catalytic properties by virtue of the structural design and spatial confinement effect available for conjugated microporous polymers.

Lotus-leaf-derived activated carbon materials (denoted as LAC-T) were fabricated at different temperatures (T = 600, 700, and 800 °C), which resulted in carbonaceous materials with various microstructures and porosity. BET surface area of LAC-T increased from 1184 m 2 g −1 to 1807 m 2 g −1 with activation temperatures that varied from 600 °C to 800 °C. These microporous carbonaceous materials were subsequently advanced as ideal platforms for cadmium sulfide (CdS) composite photocatalysts, through the deposition of nano-CdS precursors on LAC-

A 1D CdZnS nanorod solid solution with rich sulfur vacancies achieved excellent photocatalytic hydrogen production under visible irradiation.