Solution-processed hybrid solar cells employing a low band-gap polymer and PbSx Se1-x alloy nanocrystals, achieving a record high PCE of 5.50% and an optimal FF of 67% are presented. The remarkable device efficiency can be attributed to the high-performance active materials, the optimal polymer/NCs ratio and, more importantly, the vertical donor/(donor:acceptor)/acceptor structure which benefits charge dissociation and transport.

We demonstrate a hybrid Schottky junction solar cell based on methyl/allyl groups terminated silicon nanowire arrays (SiNWs) and poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) with a power conversion efficiency (PCE) of 10.2%. The methyl/allyl organic monolayer on silicon can act as an excellent passivation layer for suppressing surface charge recombination, which is characterized by grazing angle attenuated total reflectance Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy measurements. The transient and steady electric output characteristics measurements indicate that the density of trap states of SiNWs are dramatically suppressed by methyl/allyl surface modification. In addition, the device based on methyl/allyl passivated SiNWs exhibits improved stable electrical output over those based on either methyl or allyl passivated ones. The improved PCE and good stability of the device are ascribed to efficient functionalization of the SiNW surface.

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Hg2+quenched CNPs (CNP-Hg2+) as a highly sensitive and selective reversible probe for the detection of mercapto biomolecules in aqueous solutions and in living cells.

Oxygen vacancies in MoOx play an essential role in interface energetics for charge injection and transport in organic devices. The influence of oxygen vacancy on energy-level alignment at the interface between MoOx and organic hole-transport layers is studied via photoemission spectroscopy. The degree of oxygen vacancies in MoOx is controlled by thermal annealing, which results in the partial reduction of Mo cations and a decrease in their work function. The hole-injection barrier at MoOx/organic interfaces increases as a consequence of the increase in oxygen deficiency.

The electronic structures of cesium carbonate (Cs2CO3) doped 4,7-diphenyl-1,10-phenanthroline (BPhen) films with various doping concentration are characterized by in situ ultraviolet and x-ray photoelectron spectroscopies, in an attempt to understand the mechanism of electron-transport enhancement in Cs2CO3-doped organic electron-transport layer for organic optoelectronic devices. The n-type electrical doping effect is evidenced by the Fermi level shift in the Cs2CO3-doped BPhen films toward unoccupied molecular states with increasing doping concentration, leading to increase in electron concentration in the electron-transport layer and reduction in electron injection barrier height. These findings originate from energetically favorable electron transfer from Cs2CO3 to BPhen.

A facile solution processable and low temperature (≤150 °C) approach was developed to deposit ZnO electron transport interlayers for inverted organic solar cells. The ZnO thin films were fabricated from the stable and non-toxic aqueous precursor solutions of ammine-hydroxo zinc complex, [Zn(NH3)x](OH)2. The resulting inverted poly (3-hexylthiophene): [6-6]-phenyl C61 butryric acid methyl ester solar cells exhibited power conversion efficiency of 4.17% as well as decent stability. We demonstrate that the work function of the ZnO electron transport interlayers was critical in terms of governing the photovoltaic performance of the inverted devices.

Honeycomb-like mesoporous pyrite FeS2 microspheres, with diameters of 500-800 nm and pore sizes of 25-30 nm, are synthesized by a simple solvothermal approach. The mesoporous FeS2 microspheres are demonstrated to be an outstanding counter electrode (CE) material in quantum dot sensitized solar cells (QDSSCs) for electrocatalyzing polysulfide electrolyte regeneration. The cell using mesoporous FeS2 microspheres as CE shows 86.6% enhancement in power conversion efficiency (PCE) than the cell using traditional noble Pt CE. Furthermore, it also shows 11.4% enhancement in PCE than the cell using solid FeS2 microspheres as CE, due to the mesoporous structure facilitating better contact with polysulfide electrolyte and fast diffusion of redox couple species in electrolyte.