No abstract

No abstract

In this work, improved solar cells from aqueous CdTe NCs is achieved by replacing evaporated MoOx with spiro-OMeTAD as a hole transfer layer. The increased Voc and Jsc can be attributed to interfacial dipole effect and reduced back recombination loss, respectively. A high PCE of 6.56% for solar cells from aqueous NCs is obtained by optimizing the microstructure further.

No abstract

Rapid growth in the world’s economy depends on a significant increase in energy consumption. As is known, most of the present energy supply comes from coal, oil, and natural gas. The overreliance on fossil energy brings serious environmental problems in addition to the scarcity of energy. One of the most concerning environmental problems is the large contribution to global warming because of the massive discharge of CO2 in the burning of fossil fuels. Therefore, many efforts have been made to resolve such issues. Among them, the preparation of valuable fuels or chemicals from greenhouse gas (CO2) has attracted great attention because it has made a promising step toward simultaneously resolving the environment and energy problems. This article reviews the current progress in CO2 conversion via different strategies, including thermal catalysis, electrocatalysis, photocatalysis, and photoelectrocatalysis. Inspired by natural photosynthesis, light-capturing agents including macrocycles with conjugated structures similar to chlorophyll have attracted increasing attention. Using such macrocycles as photosensitizers, photocatalysis, photoelectrocatalysis, or coupling with enzymatic reactions were conducted to fulfill the conversion of CO2 with high efficiency and specificity. Recent progress in enzyme coupled to photocatalysis and enzyme coupled to photoelectrocatalysis were specially reviewed in this review. Additionally, the characteristics, advantages, and disadvantages of different conversion methods were also presented. We wish to provide certain constructive ideas for new investigators and deep insights into the research of CO2 conversion.

Efficient aqueous processed polymer–nanocrystal hybrid solar cells are demonstrated based on MPPV with a wide band gap. A PCE of 5.18% is achieved which is the highest for solar devices via an aqueous process. This work may provide a new way to develop hybrid solar cells.

Aqueous processed nanocrystal (NC) solar cells are attractive due to their environmental friendliness and cost effectiveness. Controlling the bandgap of absorbing layers is critical for achieving high efficiency for single and multijunction solar cells. Herein, we tune the bandgap of CdTe through the incorporation of Se via aqueous process. The photovoltaic performance of aqueous CdSexTe1-x NCs is systematically investigated, and the impacts of charge generation, transport, and injection on device performance for different compositions are deeply discussed. We discover that the performance degrades with the increasing Se content from CdTe to CdSe. This is mainly ascribed to the lower conduction band (CB) of CdSexTe1-x with higher Se content, which reduces the driving force for electron injection into TiO2. Finally, the performance is improved by mixing CdSexTe1-x NCs with conjugated polymer poly(p-phenylenevinylene) (PPV), and power conversion efficiency (PCE) of 3.35% is achieved based on ternary NCs. This work may provide some information to further optimize the aqueous-processed NC and hybrid solar cells.

a b s t r a c tMnO 2 is an effective adsorbent for many metal ions and a promising electrode material for electrochemical supercapacitors. In this paper, we successfully combined the two functions through preparing a MnO 2 /carbon fiber (CF) composite as an electrosorptive electrode. The thin MnO 2 film was deposited onto CF by an anodic eletrodeposition method. The MnO 2 /CF electrodes had ideal pseudocapacitive behavior and high capacitive reversibility. The specific capacitance of the MnO 2 /CF electrode reached a maximum value of 387 F/g, which is quite competitive compared with literature values. At 0.8 V applied potential, the maximum Cu 2+ adsorption capacity of the MnO 2 /CF electrode was 172.88 mg/g, which is more than 2 times higher than common MnO 2 adsorbents without an electric field imposed. SEM images showed that MnO 2 nanoflowers with several ''petals'' were uniformly distributed on the CF surface. Enhancement of adsorption by the polarization potential and the unique microstructure of the deposited MnO 2 may be the source of the outstanding adsorption ability of the MnO 2 /CF electrode. The MnO 2 /CF electrode could be regenerated quickly by reversing the voltage. The deposition time of 1000 s was optimum for achieving maximum capacitance and Cu 2+ removal performance. The MnO 2 /CF composite electrosorptive electrode is a promising candidate for Cu 2+ removal from aqueous solution.