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Molecular photoswitch can effectively regulate charge separation (CS) and charge recombination (CR) in donor‐acceptor (D‐A) systems. However, deformation of the donor‐switch‐acceptor (D‐S‐A) systems caused by the switch isomerization will destroy the geometrical stability of the battery. Here we take the planar platinum(II) terpyridyl complex of [Pt(tBu3tpy)(−C≡C−Ph)n]+ as the typical D‐A model, designed six D‐S‐A systems using different photoswitches (dimethyldihydropyrene, fulgimide, arylazopyrazole, N‐salicylideneaniline, spiropyran, and dithienylethene, denoted as D‐S‐A 1–6 hereafter). Our investigations show that the D‐S‐A 1–6 can absorb visible light of 799 nm, 673 nm, 527 nm, 568 nm, 616 nm, and 629 nm, facilitating electrons transfer from the donor and the switch to the acceptor through the Switch‐on channel. Then cationic character of the photoswitch can undergo much more rapid isomerization than the neutral form due to the lower energy barrier. The Switch‐off isomer breaks the conjugation of the D‐S‐A system, effectively turning off the CT channel and forming the CS state. Based on the evaluated conjugated backbone twist (CBT) angle, we found that D‐S‐A 1, 2, 4, 6 exhibit little configurational change and can be good candidates as the organic solar cell. The proposed D‐S‐A design controlled by the molecular switch may help to develop a solution for solar‐harvesting practical applications. [ABSTRACT FROM AUTHOR]

The introduction of a self‐adaptive molecular switch is an appealing strategy to achieve complete charge separation (CS) in donor‐acceptor (D‐A) systems. Here, we designed donor‐switch‐acceptor (D‐S‐A) systems using a platinum(II) terpyridyl complex as the acceptor, dimethyldihydropyrene/cyclophanediene (DHP/CPD) as the bridge, and methoxybenzene, thieno[3,2‐b]thiophene, 2,2′‐bifuran, and 4,8‐dimethoxybenzo[1,2‐b:4,5‐b′]difuran as donors, respectively. We then systematically studied the whole opto‐electronic conversion process of the donor‐DHP/CPD‐acceptor (D‐DHP/CPD‐A) systems based on time‐dependent density functional theory, time‐dependent ultrafast electron evolution, and electron transport property calculations. We first found that the substitution of −CH3 by −H and −CN groups in DHP/CPD can enlarge the range of the adsorption wavenumber in opto‐electric conversion. Then the light absorption induces the cationization of DHP switch, largely accelerating the forth‐isomerization to CPD form. Once the D‐CPD‐A molecule is formed, the poor conjugation can realize the complete CS state by inhibiting the radiative and nonradiative charge recombinations. Finally, the repeatable and complete CS can be achieved through the automatic back‐isomerization of CPD to DHP. The present work provides valuable insights into design of D‐S‐A systems for practical utilization of molecule‐based solar harvesting. [ABSTRACT FROM AUTHOR]

One-dimensional (1D) CeO2/Bi2WO6 heterostructured nanofibers with a diameter of about 300 nm were successfully synthesized by using a straightforward strategy combining an electrospinning technique with a sintering process. The acquired products were characterized by thermogravimetric and differential scanning calorimetric (TG-DSC), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET) surface area measurements, and UV/Vis spectroscopy. The obtained CeO2/Bi2WO6 heterostructured nanofibers exhibited an excellent photocatalytic property for the degradation of Rhodamine B (RhB) dye driven by visible light due to the promoted separation of photoelectrons and holes and the large contact area between the photocatalyst and organic pollutant. [ABSTRACT FROM AUTHOR]