Photocatalytic heterogeneous organic transformation is considered as an efficient, clean atomic economy, and low-energy consumption strategy for organic synthesis. Conjugated polymers (CPs)-based materials have recently shown great potential for diverse photocatalytic applications because of their unique properties, such as structural designability, recyclability, high chemical stability, and low cost, and they have emerged as promising alternatives to traditional molecular or inorganic photocatalyst in photoredox reactions. Immense efforts have been made toward the construction of CPs-based materials for versatile photocatalytic chemical transformations. In this Review, we aim to summarize the recent progress in CPs-based photocatalysts for heterogeneous photocatalytic organic transformations including oxidation, reduction, coupling, and cycloaddition reaction. This Review discusses the influence of molecular, electronic, and channel structure of CPs-based materials on light absorption, charge separation, and mass transfer in different photocatalytic photoredox reactions. The regulated synthesis, mechanistic discussions, and future challenges for heterogeneous photocatalytic organic transformation in CPs-based materials systems are also considered. It is expected that this Review could not only deepen the comprehension of photocatalytic organic transformation but also open up inspirations and feasibilities for the applications of CPs-based materials.

IntroductionConverting solar light into chemical energy such as hydrogen via artificial photosynthesis is a promising approach to address Solar-driven water splitting is in urgent need for sustainable energy research, for which accelerating oxygen evolution kinetics along with charge migration is the key issue. Herein, Mn 3+ within π-conjugated carbon nitride (C 3 N 4 ) in form of Mn-N-C motifs is coordinated. The spin state (e g orbital filling) of Mn centers is regulated by controlling the bond strength of Mn-N. It is demonstrated that Mn serves as intrinsic oxygen evolution reaction (OER) site and the kinetics is dependent on its spin state with an optimized e g occupancy of ≈0.95. Specifically, the governing role of e g occupancy originates from the varied binding strength between Mn and OER intermediates. Benefiting from the rapid spin state-mediated OER kinetics, as well as extended optical absorption (to 600 nm) and accelerated charge separation by intercalated metal-to-ligand state, Mn-C 3 N 4 stoichiometrically splits pure water with H 2 production rate up to 695.1 µmol g −1 h −1 under simulated sunlight irradiation (AM1.5), and achieves an apparent quantum efficiency of 4.0% at 420 nm, superior to most solid-state based photocatalysts to date. This work for the first time correlates photocatalytic redox kinetics with the spin state of active sites, and suggests a nexus between photocatalysis and spin theory.

We established an experimental setup for generating partially coherent beams with different complex degrees of coherence, and we report experimental generation of an elliptical Gaussian Schell-model (GSM) beam and a Laguerre-GSM beam for the first time. It has been demonstrated experimentally that an elliptical GSM beam and a Laguerre-GSM beam produce an elliptical beam spot and a dark hollow beam spot in the focal plane (or in the far field), respectively, which agrees with theoretical predictions. Our results are useful for beam shaping and particle trapping.

Cosine-Gaussian-correlated Schell-model sources whose degree of coherence (DOC) is of circular symmetry have been introduced just recently [Opt. Lett. 38, 2578 (2013)]. In this Letter, we propose a model for a source whose DOC is the superposition of two 1D cosine-Gaussian-correlated Schell-model sources, i.e., possesses rectangular symmetry. The novel model sources and beams they generate are termed rectangular cosine-Gaussian Schell-model (RCGSM). The RCGSM beam exhibits unique features on propagation, e.g., its intensity in the far field (or in the focal plane) displays a four-beamlet array profile, being qualitatively different from the ring-shaped profile of the CGSM beam whose DOC is of circular symmetry. Furthermore, we have carried out experimental generation of the proposed beam and measured its focusing properties. Our experimental results are consistent with the theoretical predictions.

Partially coherent beam is preferred in many applications, such as free-space optical communications, remote sensing, active laser radar systems, etc., due to its resistance to the deleterious effects of atmospheric turbulence. In this paper, after presenting a historical overview on propagation of optical beams in turbulent atmosphere, we describe the basic theory for treating the propagation of optical beams in turbulent atmosphere and we mainly introduce recent theoretical and experimental developments on propagation of partially coherent beam in turbulent atmosphere. Recent progress on the interaction of a partially coherent beam with a semirough target in turbulent atmosphere and the corresponding inverse problem are also reviewed.

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