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Integrating solar energy into rechargeable battery systems represents a significant advancement towards sustainable energy storage solutions. Herein, we propose a win‐win solution to reduce the shuttle effect of polysulfide and improve the photocorrosion stability of CdS, thereby enhancing the energy conversion efficiency of rGO/CdS‐based photorechargeable integrated lithium‐sulfur batteries (PRLSBs). Experimental results show that CdS can effectively anchor polysulfide under sunlight irradiation for 20 minutes. Under a high current density (1 C), the discharge‐specific capacity of the PRLSBs increased to 971.30 mAh g−1, which is 113.3 % enhancement compared to that of under dark condition (857.49 mAh g−1). Remarkably, without an electrical power supply, the PRLSBs can maintain a 21 hours discharge process following merely 1.5 hours of light irradiation, achieving a breakthrough solar‐to‐electrical energy conversion efficiency of up to 5.04 %. Ex situ X‐ray photoelectron spectroscopy (XPS) and in situ Raman analysis corroborate the effectiveness of this complementary weakness approach in bolstering redox kinetics and curtailing polysulfide dissolution in PRLSBs. This work showcases a feasible strategy to develop PRLSBs with potential dual‐functional metal sulfide photoelectrodes, which will be of great interest in future‐oriented off‐grid photocell systems. [ABSTRACT FROM AUTHOR]

MXene, a new class of 2D layered materials, is considered a candidate for the reverse electrodialysis (RED) film because the laminated MXene nanochannels with charged functional groups provide an excellent ionic selectivity and conductivity. However, the MXene‐based ion‐exchange films suffer from weak mechanical properties and instability in water due to the poor binding force between the nanosheets, which limits their RED performance. Here, inspired by natural nacre structure, a class of cation‐MXene/cation holocellulose nanofibers (C‐MXene/C‐HNF) composite film with high performance for harvesting nanofluidic osmotic is developed. C‐HNF acts as interlocking agent to connect the MXene nanosheets by hydrogen bonding, resulting a mechanically robust and water stable film. The introduction of C‐HNF not only increases the interlayer interaction force, but also enhances the ion transport flux. When the content of C‐HNF is 20%, the tensile stress, fracture strain, and toughness of the composite film reach up to 127.75 ± 1.61 MPa, 3.50 ± 0.1%, and 2.95 ± 0.52 MJ m−3, respectively. Additionally, the composite film can produce an impressive output power density of up to 1.09 W m−2 under a 50‐fold salinity gradient (0.01/0.5 m NaCl), and only decreases by 4.58% after 50 days, demonstrating good stability and durability. [ABSTRACT FROM AUTHOR]

TiO2 has garnered a flourish of interest in the field of energy storage and energy conversion. Herein, a new generation of 3D Ni foam supported in situ grown 1D TiO2 nanoarray (Ni/TiO2) is successfully prepared, through an easy solution‐phase hydrothermal process, and then CdS nanorods branched Ni/TiO2 nanoarrays are fabricated (Ni/TiO2@CdS). Their formation parameters and growth mechanism are carefully studied. Both Ni/TiO2 and Ni/TiO2@CdS monolithic catalysts exhibit advantaged photocatalytic (PC) and photoelectrocatalytic (PEC) water splitting properties compared with that of most previously reported TiO2‐based film photocatalysts. Mechanism investigation reveals that both type II and Z‐scheme charge transport mechanisms coexist in Ni/TiO2@CdS sample, and an additional Z‐scheme charge transfer effect accelerates the photogenerated charge separation and transport efficiency. This study may open a new avenue for the utilization of TiO2‐based film catalysts in a broader field of energy and environmental catalysis areas. [ABSTRACT FROM AUTHOR]

Superoxide decay behavior is evaluated by contrastive potential energy surface analyses from theoretical calculations. The presence of carbon surfaces enhances the superoxide decay through disproportionation instead of electroreduction, which is a non‐electrochemical reaction that impedes the increase in energy efficiency for relevant energy conversion applications. Nitrogen doping of carbon effectively retards the disproportionation by influencing the oxygen stretching vibration and changing the proton‐coupled electron transfer trend. OK with O2−decay: Superoxide decay is evaluated by contrastive potential energy surface analyses from theoretical calculations. Carbon surfaces enhance superoxide decay by disproportionation instead of electroreduction, which impedes application for energy conversion. Compared to pure carbon, nitrogen doping retards superoxide disproportionation, promoting energy conversion efficiency. [ABSTRACT FROM AUTHOR]

Mn3O4 nanoparticles encapsulated inside carbon nanospheres supported on a carbon plate (Mn3O4@CS/CP) were designed, their bifunctional electrocatalytic performance for both, the oxygen evolution reaction (OER) at the anode and the oxygen reduction reaction (ORR) at the cathode were studied in alkaline solution. The prepared Mn3O4@CS/CP catalyst exhibits excellent electrocatalytic performance towards ORR, with less negative onset potential and long durability. Combining the results of in‐situ Fourier transform infrared spectroscopy (FTIR) and density functional theory (DFT) calculations, it is revealed that Mn3O4 acts as active site for ORR to promote the transformation of OH* into OH−. In addition, Mn3O4@CS/CP possesses an excellent electrochemical OER performances with the lower overpotential along with prosper Tafel slope and robust durability. DFT calculations show the transformation from O* to OOH* is the rate determining step for OER, and Mn3O4@CS/CP shows the minimum barrier, indicating that graphene sheet on the outer of Mn3O4 improves the transformation from O* to OOH*. The oxygen electrode activity parameter (potential difference between OER at current density of 10 mA/cm2 and ORR at current density of −2 mA/cm2) on Mn3O4@CS/CP is 0.72 V, which is superior to those of most bifunctional electrocatalysts reported to date, predicting a promising application in metal‐air batteries and fuel cells. Mn3O4 nanoparticles encapsulated inside carbon nanospheres supported on a carbon plate (Mn3O4@CS/CP) are designed, which exhibit exceptionally good stability and reversibility for ORR and OER. Furthermore, the electrocatalytic mechanism is analyzed. [ABSTRACT FROM AUTHOR]

The Cover Feature shows that compared to pure carbon, nitrogen doping retards the superoxide disproportionation in the oxygen reduction reaction in an alkaline medium, thereby promoting the energy conversion efficiency. More information can be found in the Communication by Li et al. on page 1133 in Issue 6, 2019 (DOI: 10.1002/cssc.201802601). [ABSTRACT FROM AUTHOR]

Phosphorus-doped graphitic-C3N4 nanosheets coupled with BiPO4 nanorods are hydrothermally synthesized from aqueous solutions containing CH2N2, NaH2PO4, Bi(NO3)3, and HNO3 (autoclave, 483 K, 4 h), followed by calcination at 823 K for 4 h. [ABSTRACT FROM AUTHOR]