H2 System Research Articles

Proximate molecular quasar absorbers

We present results from a search for strong H2 absorption systems proximate to quasars (zabs ≈ zem) in the Sloan Digital Sky Survey (SDSS) Data Release 14. The search is based on the Lyman-Werner band signature of damped H2 absorption lines without any prior on the associated metal or neutral hydrogen content. This has resulted in the detection of 81 systems with N(H2) ∼ 1019 − 1020 cm−2 located within a few thousand km s−1 from the quasar. Compared to a control sample of intervening systems, this implies an excess of proximate H2 systems by about a factor of 4 to 5. The incidence of H2 systems increases steeply with decreasing relative velocity, reaching an order of magnitude higher than expected from intervening statistics at Δv < 1000 km s−1. The most striking feature of the proximate systems compared to the intervening ones is the presence of Ly − α emission in the core of the associated damped H I absorption line in about half of the sample. This puts constraints on the relative projected sizes of the absorbing clouds to those of the quasar line emitting regions. Using the SDSS spectra, we estimate the H I, metal and dust content of the systems, which are found to have typical metallicities of one tenth Solar, albeit with a large spread among individual systems. We observe trends between the fraction of leaking Ly − α emission and the relative absorber-quasar velocity as well as with the excitation of several metal species, similar to what has been seen in metal-selected proximate DLAs. With the help of theoretical H I-H2 transition relations, we show that the presence of H2 helps to break the degeneracy between density and strength of the UV field as main sources of excitation and hence provides unique constraints on the possible origin and location of the absorbing clouds. We suggest that most of these systems originate from galaxies in the quasar group, although a small fraction of them could be located in the quasar host as well. We conclude that follow-up observations are still required to investigate the chemical and physical conditions in individual clouds and to assess the importance of AGN feedback for the formation and survival of H2 clouds.

Thermodynamic and experimental study on the reduction and carbonization of TiO 2 through gas‐solid reaction

Titanium oxycarbide (TiCxOy) has attracted much attention recently as a soluble anode used in the USTB (University of Science and Technology Beijing) or MER (Materials and Electrochemical Research) molten-salt electrolysis process to produce sponge titanium. The present study aimed to investigate the production of titanium oxycarbide from TiO2 by using CH4–H2 gas mixture, and both thermodynamic and experimental studies were carried out. First, thermodynamic analysis in the TiO2–CH4–H2 system was performed by the method of equilibrium calculation. The analysis indicated that TiO2 could be ultimately reduced and carbonized to TiCxOy by CH4 and H2 gas at temperature above 1200°C, and the increase of temperature was theoretically favorable to the final carbonization extent of TiCxOy. The experimental process involved the reduction of both pure TiO2 powder and TiO2 with additives using methane–hydrogen gas mixture in the temperature range from 1200°C to 1450°C. Experimental results showed that pure TiO2 could be reduced completely to TiCxOy at 1350°C and above after 8-hour reduction. It was also found that the reduction extent of TiO2 increased with increasing time and temperature when at a low temperature range; however, a much higher temperature (above 1350°C) would hinder further carbonization for the production of deposited carbon. Addition of iron oxides to TiO2 powders strongly facilitated the reduction reaction, even prompting the reaction of TiO2 to TiCxOy completely at only 1200°C after 8-hour reduction. The gas-solid reaction provided a simple and quick way to produce titanium oxycarbide.

Design of Heterogeneous Photocatalysis Based on Energy-Resolved Distribution of Electron Traps

How can we design solid photocatalysts? What is the decisive factor controlling photocatalytic activities? For at least more than 35 years, since photoinduced water splitting in an electrochemical system including titania single crystal and platinum electrodes has been discovered in 1972 [1], has been passed. So-called band-structure model (BSM), electrons in a valence band (VB) of a photocatalyst is photoexcited to a conduction band (CB), leaving positive holes in VB, and electrons and holes reduce and oxidize, respectively, substrates adsorbed on the surface of the photocatalyst, does suggest preferable band positions for redox reaction uniquely decided only by crystalline structure. Possible the other factors, e.g., particle size and surface structure, cannot be discussed within BSM. Recently, we have developed reversed double-beam photoacoustic spectroscopy (RDB-PAS) which enables measure energy-resolved density of electron traps (ERDT). Those electron traps (ETs) seem to be predominantly located on the surface of almost all the metal oxide particles, with exception of nickel oxide and therefore they reflect macroscopic surface structure in ERDT patterns [2,3]. Using ERDT pattern along with the data of CB-bottom position (CBB), i.e., ERDT/CBB patterns, it has been shown that metal oxide powders can be identified without using the other analytical data such as X-ray diffraction patterns or specific surface area, and similarity/differentness of a pair of metal-oxide samples can be quantitatively evaluated as a parameter, ζ, degree of coincidence of ERDT/CBB patterns[4]. Three representative photocatalytic reactions, (a) hydrogen (H2) evolution from deaerated aqueous methanol (H2 system), (b) carbon-dioxide (CO2) evolution from aqueous acetic acid under aerobic conditions (CO2 system) and (c) oxygen (O2) evolution from aqueous silver fluoride (O2 system), were carried out with those titania samples, and the ratios of evaluated photocatalytic activities for pairs of titania samples (0 < ζ pc < 1) were compared with z as shown in Fig. 1. It is clearly seen that the higher the value of ζ at > 0.6 is, the higher becomes ζ pc, i.e., the ERDT/CBB patterns reflect bulk/surface structures which govern overall photocatalytic activities of titania samples. Then reversed analysis has been made, i.e., those ERDT/CBB patterns were arranged in the order of photocatalytic activity from higher side to lower side. Interestingly, for CO2 and O2 systems, highest activity titania samples exhibited similar patterns in each system, while middle or low-activity samples did no similarity. One of the possible reasons is that photocatalytic activities are governed by many independent factors, which are all optimized in the highest activity samples, though activities can be much reduced only by one unfavorable factor. In the other words, we cannot expect to find titania samples of activity higher than those titania samples in CO2 and O2 systems. This assumption, however, may suggest that titania samples exhibiting superior photocatalytic activity in H2 system may be discovered, because they seem not to be optimized. [1] A. Fujishima, K Honda, Nature 238 (1972) 37. [2] A. Nitta, M. Takase, M. Takashima, N. Murakami, B. Ohtani, Chem. Commun. 52 (2016) 12096. [3] A. Nitta, M. Takashima, N. Murakami, M. Takase, B. Ohtani, Electrochim. Acta 254 (2018) 83. [4] A. Nitta, M. Takashima, M. Takase, B. Ohtani, Catal. Today in press (10.1016/j.cattod.2017.12.020). Figure 1

Back Cover: Advanced Engineering Materials 5∕2019

Advanced Engineering MaterialsVolume 21, Issue 5 1970015 Back CoverFree Access Back Cover: Advanced Engineering Materials 5∕2019 First published: 21 May 2019 https://doi.org/10.1002/adem.201970015AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Graphical Abstract The protective HfC coating is uniformly deposited on the woven carbon fiber fabric at 1200°C by chemical vapor deposition based on thermodynamic calculation. H2 partial pressure in a HfCl4–C3H6–H2 system has a significant effect on the yield, composition, and morphology of the HfC coating. As H2 partial pressure becomes higher, nanostructures are more favorable than a continuous film but the co-deposition of excess carbon in HfC is effectively suppressed. Further details can be found in the article 1800730 by Daejong Kim and co-workers. Volume21, Issue5May 20191970015 RelatedInformation

Influence of polymerization among Al- and Ga-containing molecules on growth rate and Al content in AlGaN

AlGaN metalorganic vapor-phase epitaxial growth simulation in a TMAl/TMGa/NH3/H2 system was studied to explain its growth rate and Al content. We proposed three kinds of Al- and Ga-containing polymers in this system. By using those polymers, we got good agreements in pressure, TMAl/(TMAl+TMGa) inlet ratio, and temperature dependences of AlGaN growth rate and its Al content between simulations and experiments, even at pressures higher than 40 kPa. Our results showed that the formation of these polymers is enhanced under higher pressures. The simulation considering those polymers could explain the linearity in the TMAl/(TMAl+TMGa) inlet ratio dependences of growth rate and Al content at lower pressure and their non-linearity at higher pressure.

Mechanism of improved magnetizing roasting of siderite–hematite iron ore using a synergistic CO–H2 mixture

A fluidized-bed magnetizing roasting–magnetic separation process was selected to treat this type of material. Phase transformations and microstructural changes in the product resulting from magnetizing roasting under different reducing gases (CO, H2, CO + H2) were clarified by vibrating sample magnetometry, X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The results indicated that the conversion ratio and saturation magnetization of samples roasted in a mixed gas of CO and H2 were higher than those of samples produced under CO or H2 alone. This indicated that synergy of the combined CO and H2 gas had a positive effect on the fluidized-bed magnetizing roasting process. The mechanism and kinetics of the improved magnetizing roasting of a siderite–hematite iron ore mixture under this synergistic CO–H2 system were investigated under isothermal conditions. The results indicated that the apparent activation energies of the reactions of the iron oxides decreased from 37.7 and 17.9 to 15.9 kJ/mol when the roasting atmosphere was changed from pure H2 or CO to a gas mixture of CO and H2, respectively. The mixed CO–H2 gas promoted the conversion ratio of hematite and siderite to magnetite, thereby improving the conversion ratio in the fluidized-bed magnetizing roasting process.

MPC for optimal dispatch of an AC-linked hybrid PV/wind/biomass/H2 system incorporating demand response

A Model Predictive Control (MPC) strategy based on the Evolutionary Algorithms (EA) is proposed for the optimal dispatch of renewable generation units and demand response in a grid-tied hybrid system. The generating system is based on the experimental setup installed in a Distributed Energy Resources Laboratory (LabDER), which includes an AC micro-grid with small scale PV/Wind/Biomass systems. Energy storage is by lead-acid batteries and an H2 system (electrolyzer, H2 cylinders and Fuel Cell). The energy demand is residential in nature, consisting of a base load plus others that can be disconnected or moved to other times of the day within a demand response program. Based on the experimental data from each of the LabDER renewable generation and storage systems, a micro-grid operating model was developed in MATLAB© to simulate energy flows and their interaction with the grid. The proposed optimization algorithm seeks the minimum hourly cost of the energy consumed by the demand and the maximum use of renewable resources, using the minimum computational resources. The simulation results of the experimental micro-grid are given with seasonal data and the benefits of using the algorithm are pointed out.

Thermal Activation of CH4 and H2 as Mediated by the Ruthenium Oxide Cluster Ions [RuOx ]+ (x=1-3): On the Influence of Oxidation States.

Thermal gas-phase reactions of the ruthenium-oxide clusters [RuOx ]+ (x=1-3) with methane and dihydrogen have been explored by using FT-ICR mass spectrometry complemented by high-level quantum chemical calculations. For methane activation, as compared to the previously studied [RuO]+ /CH4 couple, the higher oxidized Ru systems give rise to completely different product distributions. [RuO2 ]+ brings about the generations of [Ru,O,C,H2 ]+ /H2 O, [Ru,O,C]+ /H2 /H2 O, and [Ru,O,H2 ]+ /CH2 O, whereas [RuO3 ]+ exhibits a higher selectivity and efficiency in producing formaldehyde and syngas (CO+H2 ). Regarding the reactions with H2 , as compared to CH4 , both [RuO]+ and [RuO2 ]+ react similarly inefficiently with oxygen-atom transfer being the main reaction channel; in contrast, [RuO3 ]+ is inert toward dihydrogen. Theoretical analysis reveals that the reduction of the metal center drives the overall oxidation of methane, whereas the back-bonding orbital interactions between the cluster ions and dihydrogen control the H-H bond activation. Furthermore, the reactivity patterns of [RuOx ]+ (x=1-3) with CH4 and H2 have been compared with the previously reported results of Group 8 analogues [OsOx ]+ /CH4 /H2 (x=1-3) and the [FeO]+ /H2 system. The electronic origins for their distinctly different reaction behaviors have been addressed.

Natural hydrogen continuous emission from sedimentary basins: The example of a Brazilian H2-emitting structure

Hydrogen escaping from sedimentary basins has already been described in various parts of the world. Some of these leakages have been identified by superficial circular depressions, also called “fairy circles”. Gas detection measurements, randomly repeated after a few months have shown that the amount of hydrogen present in soils is not constant neither versus time nor versus position in a given structure. Permanent monitoring gas analyzers were installed in the ground to estimate hydrogen flow outgassing from a topographical circular depression located in Brazil. Data show that a hydrogen flux occurs during the hottest moment of the day, as shown with permanent sensors set at a regular spacing. The process may look like a soil evaporation. In that same structure, other detectors show much higher and irregular gas output which present an unclear correlation as a function of ambient temperature and atmospheric pressure. The relationship with temperature suggests a role of water saturation driving the overall hydrogen fluxes. The reported geochemical data imply that (1) one measurement taken at a given hour on a structure cannot be considered as quantitative, as it varies too much with time and is also probably related to the soil perturbation induced by the shallow drilling, (2) hydrogen released through the soils of the studied structure is recharged daily, (3) hydrogen flux is high enough to reach the surface without being buffered by water or bacterial activity within the soil and (4) soil cannot be solely considered as a hydrogen sink but also, at least in some areas, as a hydrogen emitter. This appears to highlight that the subsurface may be considered in this site as a source of natural hydrogen, clearly differentiated from a biochemical system of atmospheric H2 consumed by bacteria.

Establishment of Blue Energy Center and Its Future Development

A research center focusing on salinity gradient energy (SGE), “Blue Energy center for SGE Technology (BEST)”, was newly established in Yamaguchi University in July 2018. This center is forging ahead membrane–based researches utilizing SGE towards its future’s implementation. In BEST, there are three research groups: (1) SGE conversion group, (2) Water hydrolysis group and (3) Water treatment group. Here, we introduced one of BEST ’s researches, a direct hydrogen production technique from seawater and sewage treated water by reverse electrodialysis (RED–H2 system). Since Yamaguchi is one of innovative prefectures for hydrogen applications, there is a good opportunity to generate CO2–free hydrogen (and oxygen) by the RED–H2 system at the municipal wastewater plant especially in Shunan city.

First-principles molecular dynamics simulations of single nitrogen bond structures in a N2[sbnd]H2 system under pressure

The search of single nitrogen bond phases is of fundamental interest since they are potential high energy content materials. Recently, several experiments have reported the existence of a novel NH phase with single nitrogen bonds. However, there is no detailed information on the structures and the mechanism on its formation. In this work, formation of the NH phase was investigated employing first-principles molecular dynamics at high pressure and room temperature. The results reveal that N2 reacts readily with H2 molecules under moderate pressure at room temperature. The resulting compound is composed mainly of single NN bonds. The calculated vibrational density of state at 50 GPa is in good agreement with the experimental Raman spectrum. The theoretical results offer insights into the understanding of the polymeric mechanism in nitrogen compounds.

Tantalum coating prepared by APCVD and in-vivo biological evaluation

ABSTRACTTantalum coating for bio-medical applications is prepared by atmospheric pressure chemical vapour deposition in a TaF5–H2 system on the inner wall of a stainless steel tube. The concentration of hydrogen fluoride (HF) has a significant effect on the morphology and crystallographic orientation of the tantalum coating. As the HF concentration increases, the tantalum coating gradually becomes smooth from roughness. The rougher part and the smoother part of tantalum coating reveal (200) and (110) preferred orientation, respectively. Simultaneously, the kinetic equation containing HF concentration has been developed. The calculated results from the equation show a good correspondence with the experimental results. The performance of tantalum coating with distinct morphologies on the effect of osseointegration was studied by implanting samples in vivo. The coating with a rougher surface was more osteoattractive than the one with a smoother surface.

Chemical Vapor Deposition of Dense Hafnium Carbide from HfCl4–C3H6–H2 System for the Protection of Carbon Fibers

Hafnium carbide (HfC) is studied as a promising material for aerospace application at ultra‐high temperatures. The protective HfC coating is deposited on carbon fiber at 1200 °C using a chemical vapor deposition method. Thermodynamic calculation is carried out to optimize process variables in the HfCl4–C3H6–H2 system. H2 partial pressure in the system has a significant effect on the yield, composition, and morphology of the HfC coating. When the ratio of H2/(HfCl4 + C3H6) is high, a single HfC phase with a porous structure is deposited because of the growth of HfC nanorods. On the other hand, a highly crystalline dense HfC, which contains a small amount excess carbon, is uniformly deposited on the carbon fiber woven fabric at a low H2/(HfCl4 + C3H6) ratio.

Dynamics of NO(A2Σ+ ← X2Π) photoexcitation in rare gas and H2 solid matrices

In the present work, the energy relaxation process in doped solid matrices is studied. The photoexcitation of NO molecule to its first electronic Rydberg state, being trapped in argon, neon and parahydrogen (pH2) cryogenic solids, is considered. Classical molecular dynamics (MD) simulations were used by applying a quantum correction for the temperature using anharmonic approach. Potential energy surfaces (PESs) recently performed for the NO–Ne, NO–Ar and NO–H2 systems have been used, with the aim to describe the dynamical response of the solid matrices upon NO photoexcitation. MD simulations partially reproduced the experimental results. In the case of the NO–Ne system, the results totally agree with a previous work. These are the first results for NO–H2 system using MD simulations with an ab initio PES.

Heterolysis of Dihydrogen by Nucleophilic Calcium Alkyls

Abstractβ‐Diketiminato (BDI) calcium alkyl derivatives undergo hydrogenolysis with H2 to regenerate [(BDI)CaH]2, allowing the catalytic hydrogenation of a wide range of 1‐alkenes and norbornene under very mild conditions (2 bar H2, 298 K). The reactions are deduced to take place with the retention of the dimeric structures of the calcium hydrido‐alkyl and alkyl intermediates via a well‐defined sequence of Ca−H/C=C insertion and Ca−C hydrogenation events. This latter deduction is strongly supported by DFT calculations (B3PW91) performed on the 1‐hexene/H2 system, which also indicates that the hydrogenation transition states display features which discriminate them from a classical σ‐bond metathesis mechanism. In particular, NBO analysis identifies a strong second order interaction between the filled α‐methylene sp3 orbital of the n‐hexyl chain and the σ* orbital of the H2 molecule, signifying that the H−H bond is broken by what is effectively the nucleophilic displacement of hydride by the organic substituent.

Rotational Quenching of HD in Collisions with H2: Resolving Discrepancies for Low-lying Rotational Transitions

Abstract The deuterated hydrogen molecule HD has been observed in a variety of cool molecular astrophysical environments. By virtue of its small dipole moment the HD molecule is believed to have played an important role in the cooling of the primordial gas in the formation of the first stars and galaxies. HD has also recently been proposed as a tracer of molecular hydrogen in protoplanetary disk evolution, providing a diagnostic for the total disk mass. Here we report benchmark computations of rotational quenching rate coefficients for HD in collisions with H2 based on quantum coupled channel methods within the rigid rotor model, and validate them against full-dimensional rovibrational scattering formalism. It is found that the rigid rotor model yields accurate rate coeffiicents for rotational transitions in HD+H2 collisions at astrophysically relevant kinetic temperatures. Results are reported using the most recent highly accurate interaction potentials for the H2–H2 system. We obtain excellent agreement with previous results of Schaefer for the most important Δj = ±1, ±2 transitions in HD induced by ortho- and para-H2, but find significant differences with recent results of Sultanov et al. that employed the same interaction potential as the one adopted here.

Practical approach for beryllium atomic clusters: TD-DFT potential energy surfaces from equilibrium to dissociation for excited states of 2s → 2p

To shed light on the spectroscopic energy-smearing mechanism of the recently developed technique for multi-element analysis (e.g., forensic tests on artworks), which is called plume laser-induced fluorescence, practically computer simulations need to be accurate and fast enough for generating wide-range excited-state potential energy surfaces (PESs) from equilibrium to dissociation of large (non-equilibrated) atomic clusters. Currently, all the very high-level post-Hartree–Fock theories (e.g., coupled-cluster theory) are computationally too expensive for this purpose (e.g., taking at least ~ 23 years). After considering the extensive applications of time-dependent density-functional theory (TD-DFT) in computing the optical properties of many-body systems, we wonder how TD-DFT performs in the wide-range-PES generations because no such TD-DFT application is found by us in the literature (perhaps due to its insufficient static/non-dynamical correlation energy). In this work, we carried out TD-DFT calculations on beryllium atomic clusters from Be1 to Be50 (in contrast to open-shell H2 or Li2 system, we think the individual closed-shell Be systems at the dissociation limit could help TD-DFT to describe the static/non-dynamical correlation. For example, it is usually considered that Be2 has zero non-dynamical correlation energy in the literature) with and without Tamm–Dancoff approximation (TDA). Electronic excited-state properties (e.g., PES, equilibrium position, dissociation energy, fork intersection) associated with 2s → 2p are systematically investigated at a total of 48 levels of TD-DFT. Our calculations are thoroughly benchmarked against experimental results and (very) high-level theoretical values. In short, we find that for accurate simulations, it is necessary to use diffuse basis sets and the TDA approximation. TD-DFT with the small basis set 3-21+G* took ~ 2 min to finish a single-point excitation energy calculation on a linear Be50 (a toy model), while the large basis set 6-311+G(2df,2p) took 30 min. By contrast, a couple-cluster theory EOM-CCSD with 6-311+G(2df,2p) took 2.5 h to do the same but merely for a smaller linear Be10. In general, we suggest that TD-DFT:TDA with 3-21+G* should be practically fast and accurate enough for emulating our desired wide-range excited-state PESs of large Be atomic clusters (including conical intersection points of close energies) in the future studies. Nevertheless, benchmarking work on (much) larger sizes of Be clusters will always be more desirable whenever its computational costs at very high level of theories becomes more tractable.

Some Aspects of Interactions in the Mo–W–Al2O3–H2 System: Formation of Polyoxides

The possibility of formation of molybdenum and tungsten polyoxides in the Mo–W–Al2O3–H2 system at T = 2400 K and P = 1 bar in a controlled Ar + H2 atmosphere has been investigated by the method of thermodynamic analysis. The formation of polyoxides is found to occur both due to the processes involving Al2O3 melt and in the absence of the latter. It is established that metals (Mo and W) and their mono-, di-, and even trioxides (in the latter case, mediated polymerization occurs) can be used as initial components to form polyoxides. It is shown that polyoxides themselves may interact with one of their main sources: Al2O3 melt.

Total Cost of Ownership of Fuel Cell Electric Vehicles Using Expert Assessments

We calculated the total cost of ownership (TCO) of fuel cell electric vehicles (FCEVs) in 2017, 2020, 2035, and 2050. Our TCO model incorporates proton exchange membrane fuel cell (PEMFC) cost and durability data that we obtained during our expert elicitation interviews [1]. Our assumptions, including hydrogen storage system and fuel costs, are consistent with those published by the U.S. Department of Energy [2, 3]. We characterized the uncertainty associated with FCEV life cycle costs, and we compared our FCEV projections to the DOE’s 2035 projections for internal combustion engine vehicles (ICEVs), battery electric vehicles (BEVs), hybrid-electric vehicles (HEVs), and plug-in hybrid electric vehicles (PHEVs). In our sensitivity analyses, we studied the dependence of FCEV TCO on vehicle lifetime, hydrogen fuel cost, and hydrogen storage system cost. All monetary values are expressed in 2017 USD. On median, we estimated the FCEV TCO to be $0.42/mile in 2017, $0.33/mile in 2020, $0.19/mile in 2035, and $0.18/mile in 2050 (Figure 1). Our 2017 and 2020 estimates ranged widely. Our 2017 estimates ranged from $0.40 to $0.75/mile and 2020 estimates ranged from $0.31 to $0.51/mile. By 2035, FCEVs could be competitive with ICEVs, BEVs, HEVs, and PHEVs, as long as the PEMFC stack lasts sufficiently long. If the FCEV’s lifetime falls below 11 yrs, FCEVs could become more expensive than competing vehicles. At about 11 yrs, the FCEV’s TCO exceeds that of the BEV. If stack durability remains a challenge, replacing the stack could be economical. Achieving a hydrogen fuel cost below $4/kg H2 and hydrogen system cost below $390/kg H2 could further improve FCEVs’ competitiveness.

Photocatalytic hydrogen production from acidic aqueous solution in BODIPY-cobaloxime-ascorbic acid homogeneous system

Iodinated boron dipyrromethene (BODIPY) dyes with 8-hydroxyl-quinoline or phenylamine moiety at the meso-position on the BODIPY core were used as efficient photosensitizers (PSs) of three-component light-driven production of H2 system from acidic aqueous solution in conjunction with a cobaloxime [CoIII(dmgH)2PyCl] (dmgH=dimethylglyoximate, and py=pyridine) as proton-reducing catalyst and ascorbic acid (H2A) as sacrificial electron donor. This is the first example of BODIPYs as homogeneous hydrogen-generating PSs employed in the acidic aqueous conditions. That they are active in the acidic solutions and inactive in the basic conditions may indicate that the extent of competition between intramolecular and intermolecular electron transfer reactions exists. Efficient bimolecular electron transfer reaction between PS and molecular catalyst is needed to make H2 production, while the intramolecular electron transfer of PS may curb H2 production. The results underscore that the chemical modification of BODIPYs can be performed, thus allowing for the transformation of acid and base conditions for the light-driven H2 production.