We report on the synthesis of iron-nickel sulfide (INS) ultrathin nanosheets by topotactic conversion from a hydroxide precursor. The INS nanosheets exhibit excellent activity and stability in strong acidic solutions as a hydrogen evolution reaction (HER) catalyst, lending an attractive alternative to the Pt catalyst. The metallic α-INS nanosheets show an even lower overpotential of 105 mV at 10 mA/cm2 and a smaller Tafel slope of 40 mV/dec. With the help of DFT calculations, the high specific surface area, facile ion transport and charge transfer, abundant electrochemical active sites, suitable H+ adsorption, and H2 formation kinetics and energetics are proposed to contribute to the high activity of the INS ultrathin nanosheets toward HER.

Methanol dehydrogenation to CO and H on Pd(111) is systematically investigated using self-consistent periodic density functional theory (DFT). All possible intermediates involved are calculated. Methanol and formaldehyde adsorb weakly on the Pd(111) surface because they are saturated molecules. CO and H prefer 3-fold sites with the adsorption energies of 41.6 and 64.4 kcal/mol. CH 3 O binds stably at 3-fold and bridge sites. Most of the other intermediates are inclined to adsorb to the surface with the sp 3 configuration of the carbon atom and a hydroxyl-like configuration for O, i.e., top (η 1 -C) for CH 2 OH, bridge (η 2 -C) for CHOH, 3-fold (η 3 -C) for COH, bridge (η 1 -C-η 1 -O) for CH 2 O, and 3-fold (η 2 -C-η 1 -O) for CHO. All possible dehydrogenation pathways are calculated and four different routes via initial O-H and C-H bond scissions are found. The theoretical calculations indicate the initial C-H bond scission is more favorable for methanol decomposition, while O-H bond scission is preferable to C-H bond scission for CH 2 OH and CHOH, and the most possible dehydrogenation pathway on Pd(111) thus takes place via CH 3 OH f CH 2 OH f CH 2 O f CHO f CO.

Purpose Trifluridine/tipiracil (TAS-102) was effective in patients with metastatic colorectal cancer (mCRC) in a phase II Japanese trial. This regional trial evaluated the efficacy and safety of trifluridine/tipiracil in Asian patients with mCRC with or without exposure to biologic therapy. Patients and Methods This randomized, double-blind, placebo-controlled, phase III trial was conducted at 30 sites in China, the Republic of Korea, and Thailand. Patients ≥ 18 years old with histologically or cytologically confirmed adenocarcinoma of the colon or rectum and known KRAS status who were refractory or intolerant to two or more prior chemotherapy regimens were enrolled. Eligible patients were randomly assigned (2:1 ratio; minimization method) to receive trifluridine/tipiracil (twice per day orally; 5 days on and 2 days off for 2 weeks, followed by 14 days off per cycle) or placebo. The primary end point was overall survival (intent-to-treat population). Results Between October 16, 2013, and June 15, 2015, 406 patients were randomly assigned to receive trifluridine/tipiracil (n = 271) or placebo (n = 135). Risk of death was significantly lower in the trifluridine/tipiracil arm than in the placebo arm (hazard ratio for death, 0.79; 95% CI, 0.62 to 0.99; log-rank P = .035). Median overall survival was significantly longer in the trifluridine/tipiracil than in the placebo arm (7.8 months [95% CI, 7.1 to 8.8 months] v 7.1 months [95% CI, 5.9 to 8.2 months], respectively), for a median survival follow-up time of 13.8 months (95% CI, 13.1 to 15.3 months) compared with 13.4 months (95% CI, 11.6 to 17.3 months), respectively. The incidence of serious adverse events was similar between the arms (trifluridine/tipiracil, n = 63 [23.2%]; placebo, n = 32 [23.7%]). No treatment-related deaths were reported. Conclusion Trifluridine/tipiracil has a statistically significant survival benefit compared with placebo in Asian patients with mCRC refractory or intolerant to standard chemotherapies, regardless of exposure to biologic therapy. The safety profile is similar to previous reports.

Ethanol decomposition over Pd(111) has been systematically investigated using self-consistent periodic density functional theory, and the decomposition network has been mapped out. The most stable adsorption of the involved species tends to follow the gas-phase bond order rules, wherein C is tetravalent and O is divalent with the missing H atoms replaced by metal atoms. Desorption is preferable for adsorbed ethanol, methane, and CO, while for the other species decomposition is preferred. For intermediates going along the decomposition pathways, energy barriers for the C-C, C(alpha)-H, and O-H scissions are decreased, while it is increased for the C-O path or changes less for the C(beta)-H path. For each of the C-C, C-O, and C-H paths, the Bronsted-Evans-Polanyi relation holds roughly. The most likely decomposition path is CH(3)CH(2)OH --> CH(3)CHOH --> CH(3)CHO --> CH(3)CO --> CH(2)CO --> CHCO --> CH + CO --> CO + H + CH(4) + C.

The effect of edge-functionalization on the competitive adsorption of a binary CO2-CH4 mixture in nanoporous carbons (NPCs) has been investigated for the first time by combining density functional theory (DFT) and grand canonical Monte Carlo (GCMC) simulation. Our results show that edge-functionalization has a more positive effect on the single-component adsorption of CO2 than CH4, therefore significantly enhancing the selectivity of CO2 over CH4, in the order of NH2-NPC > COOH-NPC > OH-NPC > H-NPC > NPC at low pressure. The enhanced adsorption originates essentially from the effects of (1) the conducive environment with a large pore size and an effective accessible surface area, (2) the high electronegativity/electropositivity, (3) the strong adsorption energy, and (4) the large electrostatic contribution, due to the inductive effect/direct interaction of the embedded edge-functionalized groups. The larger difference from these effects results in the higher competitive adsorption advantage of CO2 in the binary CO2-CH4 mixture. Temperature has a negative effect on the gas adsorption, but no obvious influence on the electrostatic contribution on selectivity. With the increase of pressure, the selectivity of CO2 over CH4 first decreases sharply and subsequently flattens out to a constant value. This work highlights the potential of edge-functionalized NPCs in competitive adsorption, capture, and separation for the binary CO2-CH4 mixture, and provides an effective and superior alternative strategy in the design and screening of adsorbent materials for carbon capture and storage.