(Sharecast News) - Hydrogen Group saw its shares rocket on Tuesday after a strong increase in the firm's first half revenue saw the return of an interim dividend payment and increased group expectations.The specialist recruiter recorded revenue of £68.6m for the six months ended 30 June, up 21% compared to the same period last year, and swung back to a pre-tax profit of £1.1m from a loss of £0.6m thanks to a welcome boost from its acquisition of Argyll Scott.The acquisition, which has now been successfully integrated, saw the company's net fee income leap by 57% to £14.8m, up from £9.4m a year earlier.Ian Temple, chief executive of Hydrogen, said: "I am pleased to be able to report a strong trading performance in the first six months of the year, with net fee income on a pro-forma basis up 10% on the first six months of 2017. The key objectives of the business combination with Argyll Scott have been successfully achieved and we have established a scalable platform that enables us to look forward confidently to further sustainable long-term organic profit growth."The firm's interim dividend returned at 0.5p per share following the strong results, with the firm's cash and cash equivalents down 25% from the same point last year at £3.1m."With a strong balance sheet, the group is well placed to make acquisitions and will continue to investigate potential targets. With the current levels of activity, the board is confident that the underlying profit and EPS for the full year will be substantially ahead of current market expectations," said Temple.Hydrogen Group's shares were up 15.28% at 73.20p at 1511 BST.