A simple fabrication route for ion gel nanofibers in a triboelectric nanogenerator was demonstrated. Using an electrospinning technique, we could fabricate a large-area ion gel nanofiber mat. The triboelectric nanogenerator was demonstrated by employing an ion gel nanofiber and the device exhibited an output power of 0.37 mW and good stability under continuous operation.

A ripple-structured ZnO film as the electron-collecting layer (ECL) of an inverted organic photovoltaic (OPV) was modified by atomic layer deposition (ALD) to add a ZnO thin layer. Depositing a thin ZnO layer by ALD on wet-chemically prepared ZnO significantly increased the short-circuit current (Jsc) of the OPV. The highest power conversion efficiency (PCE) of 7.96% with Jsc of 17.9 mA/cm2 was observed in the inverted OPV with a 2-nm-thick ALD-ZnO layer, which quenched electron-hole recombination at surface defects of ZnO ripples. Moreover, an ALD-ZnO layer thinner than 2 nm made the distribution of electrical conductivity on the ZnO surface more uniform, enhancing OPV performance. In contrast, a thicker ALD-ZnO layer (5 nm) made the two-dimensional distribution of electrical conductivity on the ZnO surface more heterogeneous, reducing the PCE. In addition, depositing an ALD-ZnO thin layer enhanced OPV stability and initial performance. We suggest that the ALD-ZnO layer thickness should be precisely controlled to fabricate high-performing OPVs.

In order to induce greater light absorption, nano-patterning is often applied to the metal-oxide buffer layer in inverted bulk-heterojunction(BHJ) solar cells. However, current homogeneity was significantly disturbed at the interface, leading to an efficiency that was not fully optimized. In this work, an additional PC 61 BM layer was inserted between the ZnO ripple and the photoactive layer to enhance the electron extraction. The insertion of additional PC 61 BM layer provided substantial advantages in the operation of inverted BHJ solar cells; specifically, it enhanced current homogeneity and lowered accumulation and trapping of photogenerated charges at the ZnO interface. Inclusion of the additional PC 61 BM layer led to effective quenching of electron-hole recombination by a reduction in the number of accumulated charges at the surface of ZnO ripples. This resulted in a 16% increase in the efficiency of inverted BHJ solar cells to 7.7%, compared to solar cells without the additional PC 61 BM layer.B ulk heterojunction (BHJ) solar cells based on blends of conjugated polymers and soluble fullerene derivatives have generated strong interest in the field of renewable energy because of the potential they offer to lower manufacturing costs for large area, lightweight devices 1-3 . Since the first BHJ solar cell was reported in 1995 4,5 , the power conversion efficiency (PCE) of BHJ solar cells has gradually improved due to the development of new materials and device architectures, recently reaching over 9% in single junction device [6][7][8] .The inverted device architecture in particular has gained considerable attention in the research community because of its better device stability and advantages in processing over the conventional architecture 9-14 . In the inverted structure, since the polarity of charge collection is the opposite of that in the conventional architecture; the selection of an effective electron extraction/transportation buffer layer, which can effectively build-up the symmetry breaking, is the key component for high performance inverted solar cells 15,16 . Such an electron extraction/transportation buffer layer must be highly transparent, electrically conductive, and energetically wellmatched to the lowest unoccupied molecular orbital (LUMO) level of the acceptor.In order to induce greater light absorption in the photoactive layer, nano-patterning is often applied to the metal-oxide buffer layer, which functions as the electron extraction/transportation layer. Not only on metal-oxide buffer layer, plasticizer assistied soft embossing (PASE) structure have been applied on PEDOT5PSS hole extracting layer to improve solar cell performance 17 . For P3HT5PCBM solar cells based on PASE structured PEDOT5PSS layers the averaged overall power efficiency is improved by up to 18%. Many demonstrations of successful PCE enhancement through improved charge extraction and light absorption due to light scattered by the imprinted patterns have been reported to-date [18][19][20][21] . However, in most cases, t...

We prepare three-dimensional honeycomb-like Cu0.81Co2.19O4 nanosheet arrays supported by Ni foam via electrochemical codeposition of cobalt and copper hydroxides on Ni foam followed by thermal oxidation. The codeposition with Cu changes the morphology of the cobalt hydroxide deposit to form honeycomb-like nanostructures, significantly decreasing the onset potential for oxygen evolution. The Cu0.81Co2.19O4 anode displays an exceptionally low overpotential of 290 mV at a current density of 10 mA cm–2 in 1 M KOH, and an anion-exchange membrane water electrolysis cell employing the above anode achieves a current density of 100 mA cm–2 at 1.68 V in 0.1 M KOH.