Plasmonic photocatalysis has recently facilitated the rapid progress in enhancing photocatalytic efficiency under visible light irradiation, increasing the prospect of using sunlight for environmental and energy applications such as wastewater treatment, water splitting and carbon dioxide reduction. Plasmonic photocatalysis makes use of noble metal nanoparticles dispersed into semiconductor photocatalysts and possesses two prominent features-a Schottky junction and localized surface plasmonic resonance (LSPR). The former is of benefit to charge separation and transfer whereas the latter contributes to the strong absorption of visible light and the excitation of active charge carriers. This article aims to provide a systematic study of the fundamental physical mechanisms of plasmonic photocatalysis and to rationalize many experimental observations. In particular, we show that LSPR could boost the generation of electrons and holes in semiconductor photocatalysts through two different effects-the LSPR sensitization effect and the LSPR-powered bandgap breaking effect. By classifying the plasmonic photocatalytic systems in terms of their contact form and irradiation state, we show that the enhancement effects on different properties of photocatalysis can be well-explained and systematized. Moreover, we identify popular material systems of plasmonic photocatalysis that have shown excellent performance and elucidate their key features in the context of our proposed mechanisms and classifications.

Mn 4 þ -activated fluoride compounds, as an alternative to commercial (oxy)nitride phosphors, are emerging as a new class of non-rare-earth red phosphors for high-efficacy warm white LEDs. Currently, it remains a challenge to synthesize these phosphors with high photoluminescence quantum yields through a convenient chemical route. Herein we propose a general but convenient strategy based on efficient cation exchange reaction, which had been originally regarded only effective in synthesizing nano-sized materials before, for the synthesis of Mn 4 þ -activated fluoride microcrystals such as K 2 TiF 6 , K 2 SiF 6 , NaGdF 4 and NaYF 4 . Particularly we achieve a photoluminescence quantum yield as high as 98% for K 2 TiF 6 :Mn 4 þ . By employing it as red phosphor, we fabricate a high-performance white LED with low correlated colour temperature (3,556 K), high-colour-rendering index (R a ¼ 81) and luminous efficacy of 116 lm W À 1 . These findings show great promise of K 2 TiF 6 :Mn 4 þ as a commercial red phosphor in warm white LEDs, and open up new avenues for the exploration of novel non-rare-earth red emitting phosphors.

Light-emitting diodes (LEDs) are excellent candidates for general lighting because of their rapidly improving efficiency, durability, and reliability, their usability in products of various sizes, and their environmentally friendly constituents. Effective lighting devices can be realized by combining one or more phosphor materials with chips. Accordingly, it is very important that the architecture of phosphors be developed. Although numerous phosphors have been proposed in the past several years, the range of phosphors that are suitable for LEDs is limited. This work describes recent progress in our understanding of the prescription, morphology, structure, spectrum, and packaging of such phosphors. It suggests avenues for further development and the scientific challenges that must be overcome before phosphors can be practically applied in LEDs.

Designing atomically dispersed metal catalysts for oxygen reduction reaction (ORR) is a promising approach to achieve efficient energy conversion. Herein, we develop a template-assisted method to synthesize a series of single metal atoms anchored on porous N,S-codoped carbon (NSC) matrix as highly efficient ORR catalysts to investigate the correlation between the structure and their catalytic performance. The structure analysis indicates that an identical synthesis method results in distinguished structural differences between Fe-centered single-atom catalyst (Fe-SAs/NSC) and Co-centered/Ni-centered single-atom catalysts (Co-SAs/NSC and Ni-SAs/NSC) because of the different trends of each metal ion in forming a complex with the N,S-containing precursor during the initial synthesis process. The Fe-SAs/NSC mainly consists of a well-dispersed FeN 4 S 2 center site where S atoms form bonds with the N atoms. The S atoms in Co-SAs/NSC and Ni-SAs/NSC, on the other hand, form metal−S bonds, resulting in CoN 3 S 1 and NiN 3 S 1 center sites. Density functional theory (DFT) reveals that the FeN 4 S 2 center site is more active than the CoN 3 S 1 and NiN 3 S 1 sites, due to the higher charge density, lower energy barriers of the intermediates, and products involved. The experimental results indicate that all three single-atom catalysts could contribute high ORR electrochemical performances, while Fe-SAs/NSC exhibits the highest of all, which is even better than commercial Pt/C. Furthermore, Fe-SAs/NSC also displays high methanol tolerance as compared to commercial Pt/C and high stability up to 5000 cycles. This work provides insights into the rational design of the definitive structure of single-atom catalysts with tunable electrocatalytic activities for efficient energy conversion.