This paper describes the technique designated best performer in the 2nd conference on Dialogue for Reverse Engineering Assessments and Methods (DREAM2) Challenge 5 (unsigned genome-scale network prediction from blinded microarray data). Existing algorithms use the pairwise correlations of the expression levels of genes, which provide valuable but insufficient information for the inference of regulatory interactions. Here we present a computational approach based on the recently developed context likelihood of related (CLR) algorithm, extracting additional complementary information using the information theoretic measure of synergy and assigning a score to each ordered pair of genes measuring the degree of confidence that the first gene regulates the second. When tested on a set of publicly available Escherichia coli gene-expression data with known assumed ground truth, the synergy augmented CLR (SA-CLR) algorithm had significantly improved prediction performance when compared to CLR. There is also enhanced potential for biological discovery as a result of the identification of the most likely synergistic partner genes involved in the interactions.

Additives are widely adopted for efficient perovskite solar cells (PSCs), and proper additive design contributes a lot to PSCs' various breakthroughs. Herein, a novel additive of N,1-fluoroformamidinium iodide (F-FAI), whose cation replaces one amino group in guanidinium (GA + ) with electron-withdrawing fluorine group, is synthesized and applied as the additive for PSCs. The electron-withdrawing effect of fluorine promotes the molecular polarity of N,1-fluoroformamidine (F-FA), enhancing the interaction of N,1-fluoroformamidinium (F-FA + ) with MAPbI 3 . Compared with the nonpolar GA + , F-FA + improves the crystallinity, passivates the defect, and downshifts the Fermi level of MAPbI 3 more significantly. The charge transfer and built-in field in printable triple mesoscopic PSCs are therefore enhanced. Moreover, charge transport in MAPbI 3 is also promoted by F-FAI. With these benefits, a power conversion efficiency of 17.01% for printable triple mesoscopic PSCs with improved open-circuit voltage and fill factor is obtained with the addition of F-FAI, superior to the efficiency of 15.24% for those devices with guanidinium iodide additives.

The planar SnO 2 electron transport layer (ETL) has contributed to the reported power conversion efficiency (PCE) record of perovskite solar cells (PSCs), while the high-temperature mesoporous SnO 2 ETL (mp-SnO 2 ) brings poor device performance. Herein, we report the application of mp-SnO 2 for efficient printable PSCs via oxygen vacancy (OV) management by introducing magnesium (Mg) into the paste. We find that high-temperature annealing suppresses self-doping of SnO 2 by reducing OVs. The introduced Mg occupies both the Sn site and interstitial site of SnO 2 and promotes the formation of OVs. Lattice Mg tends to induce neutral OVs and interstitial Mg could promote the ionization of neutral OVs for self-doping. The synergy effect on OVs increases the carrier density and upshifts the Fermi level energy of mp-SnO 2 , ensuring its capability as the well-performed ETL with trap-less charge transport and suppressed surface recombination for dramatic improved device PCE from 6.62 % to 17.25 %.

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Halide perovskite solar cells (PSCs) have drawn worldwide attention due to their great potential to be promising candidates for highly efficient and cost-effective photovoltaic technologies. [1] Benefiting from the excellent optoelectronic properties of halide perovskites together with previous abundant experience in other solar cells, especially in dye-sensitized solar cells and organic solar cells, the power conversion efficiency (PCE) of conventional PSCs has been boosted to 25.5%, [2] making PSCs one of the most efficient solar cell type. Conventional efficient PSCs in lab usually rely on costly materials such as gold or silver electrode and organic hole transport materials (HTM). [3] To further reduce the material and fabrication cost of PSCs toward commercialization, carbon electrode-based HTM-free perovskite solar cells (C-PSCs) are developed. [4] In C-PSCs, carbon electrodes (CEs) are chosen to replace metal electrodes due to their excellent adjustable electronic properties, chemical stability and low cost. [5] However, the efficiency of C-PSCs has not exceeded 20%. [6] Therefore, developing carbon materials for C-PSCs to promote their efficiency toward the comparable level as conventional PSCs is in great demand. [4] Since no additional HTM is applied in C-PSCs, adjusting the work function (WF) of CEs to realize more efficient hole extraction and more suitable energy level alignment is an effective strategy to enhance the efficiency of C-PSCs. [7,8] To realize this, Jiang et al. introduced p-type metal oxides into the CE to improve its WF for extracting holes. [9] However, the introduction of those metal oxides led to the sheet resistance increase of CEs, which resulted in series resistance increase of the C-PSCs and restricted the efficiency improvement. Doping graphite has been demonstrated as another effective method to adjust the CEs WF for improving C-PSCs performance. Duan et al. improved the efficiency of C-PSCs from 12.4% to 13.6% by applying boron-doped carbon as the electrode. [5] Yang's group improved the WF of CE and the efficiency of C-PSCs by doping graphite with boron. [10] In addition, it is found that introducing oxygen-containing functional groups into the CE can also increase the WF. Tian et al. synthesized a carbon black with much higher oxygen content and a much higher WF than common carbon black. [11] When applying it in the CE for C-PSCs, the device efficiency was enhanced from 13.6% to 15.7%. This work demonstrated that introducing oxygen into CEs is of great potential to improve C-PSCs efficiency. However, the restriction is that the related process for introducing oxygen is carried out at high temperature of about 1600 K. Therefore, developing facile methods to synthesize oxygen-rich carbon materials sustainably for CEs is worth exploring.Biomass materials, which hold the "Sustainable and green" characteristics, have been applied for different energy conversion devices. [12][13][14] Zhu et al. synthesized a ZrO 2 @cellulose acetatereinforced nanofibrous membrane for sodium-ion b...

The power conversion efficiency (PCE) of single-junction perovskite solar cells (PSCs) is being rapidly promoted towards their theoretical limit, with a certified value of 25.7%. Reducing optical loss will further contribute to PCE improvement. Here, the optical loss including reflection loss, absorption loss, and transmission loss in printable mesoscopic perovskite solar cells (p-MPSCs) is analyzed. A printable mesoporous SiO 2 antireflection coating for improving the transmittance of the fluorine-doped tin oxide (FTO) glass substrate by reducing optical reflection at the air/glass interface is reported. With modulated porosity and thickness, the mesoporous SiO 2 film constructs a graded refractive index interface and increases the transmittance of FTO glass by ≈2%-4% in the spectral range of 350-800 nm at normal incident angle with the highest transmittance improved from 85% to 89%. The SiO 2 coating also exhibits wide-angle and broadband antireflection properties. The coatings successfully help p-MPSCs obtain about an average 3% enhancement in the short-circuit current density (J SC ) and PCE. This study demonstrates the necessity of optical management for efficient solar cells and provides a cost-effective and scalable antireflection coating for the future realistic application of PSCs.

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Perovskite solar cells (PSCs) are considered to be the most promising next‐generation photovoltaic technology. Among all the configurations of PSCs, the printable hole‐conductor‐free mesoscopic PSC (p‐MPSC) has unique advantages on low cost, large‐area fabrication and fabulous stability, which endows it with the greatest potential for industrialization. The interfacial recombination losses, especially at the perovskite/carbon interface, are the bottleneck for further improving the power conversion efficiency (PCE) of p‐MPSCs. 2‐Bromo‐6‐fluoronaphthalene is introduced as an interfacial modulator for p‐MPSCs through post‐treatment. The bromo‐terminal acts as an electrophilic site to interact with the iodine ion in perovskite via the noncovalent halogen bond. Meanwhile, the fused ring of naphthalene is capable to accommodate electron density that is attracted from the perovskite. This interaction induces a more favorable band structure at the interface. The hole extraction is promoted and the interfacial nonradiative recombination is inhibited. Accordingly, a champion p‐MPSC with an improved PCE of 16.77% from 15.50% of the pristine device is obtained.